Language disorders in children with central nervous system injury

NIH Public Access Author Manuscript J Clin Exp Neuropsychol. Author manuscript; available in PMC 2011 March 15. NIH-PA Author Manuscript Published in final edited form as: J Clin Exp Neuropsychol. 2010 April ; 32(4): 417–432. Language disorders in children with central nervous system injury Maureen Dennis Program in Neurosciences and Mental Health, The Hospital for Sick Children, Toronto, Ontario, Canada, and Departments of Surgery & Psychology, University of Toronto, Toronto, Ontario, Canada Abstract NIH-PA Author Manuscript Children with injury to the central nervous system (CNS) exhibit a variety of language disorders that have been described by members of different disciplines, in different journals, using different descriptors and taxonomies. This paper is an overview of language deficits in children with CNS injury, whether congenital or acquired after a period of normal development. It first reviews the principal CNS conditions associated with language disorders in childhood. It then describes a functional taxonomy of language, with examples of the phenomenology and neurobiology of clinical deficits in children with CNS insults. Finally, it attempts to situate language in the broader realm of cognition and in current theoretical accounts of embodied cognition. Keywords Language disorders; Pragmatic; Semantic; Syntactic; Motor speech; Central nervous system injury INTRODUCTION NIH-PA Author Manuscript Children and adolescents identified with injury to the central nervous system (CNS) exhibit a variety of language disorders that have been described by members of different disciplines, in different journals, using different descriptors and taxonomies. This paper is an overview of language deficits in children with CNS insults, whether congenital or acquired after a period of normal development. It first reviews the principal CNS conditions associated with language disorders in childhood. It then describes a functional taxonomy of language, with examples of the phenomenology and neurobiology of clinical deficits in children with CNS insults. Finally, it attempts to situate language in the broader realm of cognition and in current theoretical accounts of embodied cognition. The scope of the paper is limited to language after CNS injury. It does not cover primary language acquisition failure (specific language impairment, SLI), language in conditions defined by abnormal behavior (e.g., autism; attention deficit hyperactivity disorder, ADHD), language associated with basic sensory loss (e.g., deafness), or language in children with mental retardation of genetic origin (e.g., Down syndrome, Fragile X syndrome, Williams– Beuren syndrome). Although these conditions are often correlated with abnormal brain development, they are not identified by CNS injury, and their language characteristics and intervention issues have been covered extensively in journal articles and in recent handbooks (e.g., Fletcher & Miller, 2005; Schwartz, 2008). Address correspondence to Maureen Dennis, Program in Neurosciences and Mental Health, Department of Psychology, The Hospital for Sick Children, 555 University Avenue, Toronto, ON, M5G 1X8, Canada ([email protected]). Dennis Page 2 CONDITIONS ASSOCIATED WITH CHILDHOOD LANGUAGE DISORDERS NIH-PA Author Manuscript In children, language can be disrupted by congenital malformations originating at various points during gestation, by birth trauma, or by brain injury acquired at a later point in development. The broadest distinction is that between congenital and acquired language disorders. Congenital conditions Unlike adults, children may be born with a significant compromise of the brain mechanisms responsible for language. A large number of congenital conditions affect language. Spina bifida meningomyelocele—Spina bifida meningomyelocele (SBM) is a neural tube defect associated with malformations of spine and brain. It occurs at a rate of 0.3–0.5 per 1,000 live births (from postdietary fortification data), a decline over the past 20 years widely attributed to the emphasis on dietary supplementations of folate acid and vitamin B (Williams, Rasmussen, Flores, Kirby, & Edmonds, 2005). NIH-PA Author Manuscript The neurobiology of SBM involves structural and microstructural abnormalities of the cerebellum, midbrain, and posterior cortex; and hypoplasia and microstructural abnormalities of white matter tracts, including the corpus callosum (Del Bigio, 1993; Dennis et al., 1981; Dennis et al., 2005; Fletcher et al., 1996; Fletcher et al., 2005; Fletcher, Dennis, & Northrup, 2000; Hannay, 2000; Hasan et al., 2008). Inborn errors of metabolism—Systemic metabolic disorders that result in the accumulation of metabolites in the bloodstream cause brain disruption that may include speech and language deficits. Some of the inborn errors of metabolism that have been shown to affect speech and language include phenylketonuria (an absence of the enzyme phenylalanine), galactosemia (an inability to utilize the sugars galactose and lactose because of disordered carbohydrate metabolism), Wilson disease (a progressive degenerative disorder of the brain and liver resulting from inability to process dietary copper), Sanfilippo syndrome (an autosomal recessive enzyme deficiency; Valstar, Ruijter, van Diggelen, Poorthuis, & Wijburg, 2008), and congenital hypothyroidism (Ozanne, Murdoch, & Krimmer, 1990). NIH-PA Author Manuscript Unilateral congenital pathology—Because of the common association of adult language disorders with left hemisphere brain insult, children with congenital damage to one side of the brain are of interest to theories of language development, language lateralization, and functional age-based plasticity. Although much theoretically interesting information about language has emerged from the study of early focal lesions (e.g., Bates, Thal, & Janowsky, 1992; Bates, Vicari, & Trauner, 1999), children with complete removal of one hemisphere have been of particular interest: They represent an extreme form of unilateral brain injury; cases have similar volumes of lateralized brain damage; and the congenital malformations in some series are identical on left and right sides (e.g., Hoffman, Hendrick, Dennis, & Armstrong, 1979), allowing exploration of differences in laterality unconfounded by differences in pathology. Childhood-acquired conditions Like adults, children can exhibit language disorders from injury to the central nervous system after a period of normal development. Childhood-acquired language disorder, or childhood-acquired aphasia, refers to language impairment evident after a period of normal language acquisition that is precipitated by, or associated with, an identified form of brain insult. J Clin Exp Neuropsychol. Author manuscript; available in PMC 2011 March 15. Dennis Page 3 NIH-PA Author Manuscript Seizure disorders—Seizure disorders may be associated with language deficits (Williams & Sharp, 2000), and language symptoms may be part of clinical seizures or part of ictal speech automatisms. The most studied seizure disorder is the Landau–Kleffner syndrome (Denes, 2008; Landau & Kleffner, 1957), which involves acquired aphasia with convulsive disorder and agnosia for sounds in children who acutely or progressively lose previously acquired language (Appleton, 1995; Majerus, Van der Linden, Poncelet, & Metz-Lutz, 2004). Vascular disorders—Vascular disorders involve interruptions to the blood supply within the brain as a result of occlusion (ischemic stroke) or rupture (hemorrhagic stroke). Degenerative disorders like atherosclerosis are rare in children, while vascular strokes associated with congenital heart disease occur in childhood (Ozanne & Murdoch, 1990), from an embolism from the heart, complications of heart surgery, or hypoperfusion from prolonged hypotension, or from sickle cell disease (Ris & Grueneich, 2000). The neurobiology of childhood strokes is variable. Many childhood strokes are secondary to intracranial occlusive disease in the basal ganglia, although cortical vascular lesions in the left temporoparietal lobe that produce aphasia occur from cerebral arteritis (Dennis, 1980b) or ruptured arteriovenous malformations (Hynd, Leathem, Semrud-Clikeman, Hern, & Wenner, 1995). NIH-PA Author Manuscript Traumatic brain injury—Children exhibit a range of language disturbances in the acute phase after head injury (Guttmann, 1942; Jordan, 1990; Loonen & Van Dongen, 1990; Van Dongen & Loonen, 1977), a common cause of childhood-acquired language disorders. The neurobiology of childhood traumatic brain injury (TBI) includes immediate impact injury (contusions, diffuse axonal damage), secondary intracranial events (hematomas, brain swelling, infections, subarachnoid hemorrhages, hydrocephalus), and extracranial factors (hypoxia, hypotension). TBI results in focal brain damage (vascular injury involving contusions and hemorrhage, especially in the frontal and temporal lobes) and diffuse brain damage (to axons in the white matter), as well as in secondary damage such as raised intracranial pressure, hypoxia, and ischemia (Gennarelli & Graham, 1998). Brain tumors—Brain tumors in children are often associated with language disturbances (Hudson, 1990; Van Dongen & Paquier, 1991). The neurobiology of brain tumors depends on the tumor etiology, size, and location. The most studied form of childhood brain tumors are posterior fossa tumors, such as malignant medulloblastomas and benign astrocytomas, which occur with relatively high frequency in children, and which are associated with speech and language deficits (Dennis, Spiegler, Riva, & MacGregor, 2004). NIH-PA Author Manuscript Cancer treatments—Radiotherapy and chemotherapy, which are often part of the treatment for childhood cancers such as acute lymphoblastic leukemia or malignant brain tumors, cause structural and functional damage to the brain (Withers, 1992). Long-term survivors of acute lymphoblastic leukemia treated with radiation and chemotherapy show cognitive deficits that include language impairments (Hudson, Buttsworth, & Murdoch, 1990; Moleski, 2000). Infectious conditions—Infectious diseases of the brain, which may involve viral, bacterial, spirochetal, and other microorganisms that infect the meninges or the brain, may affect language (Anderson & Taylor, 2000; Smyth, Ozanne, & Woodhouse, 1990), either as a primary effect of brain involvement in conditions like herpes simplex encephalitis, or as a secondary effect of sensorineural hearing loss in conditions such as bacterial meningitis or toxoplasmosis. J Clin Exp Neuropsychol. Author manuscript; available in PMC 2011 March 15. Dennis Page 4 NIH-PA Author Manuscript Hypoxic disorders—Anoxia, a state in which the oxygen levels in the body fall below physiologic levels because of depleted oxygen supply, can come about from various causes (including severe hypotension, cardiac arrest, carbon monoxide poisoning, near-drowning, and suffocation) that involve a drop in the level of cerebral blood flow or the oxygen content of the blood. A prolonged period of cerebral anoxia will produce permanent brain damage or anoxic encephalopathy, which is associated with a range of language deficits (Murdoch & Ozanne, 1990). LANGUAGE DISORDERS Broadly, language is a code that links linguistic representations with various levels of meaning (Caplan, 1992): of words, sentences, texts, and social–affective communication. The code can be instantiated in different modalities (auditory, visual, tactile) and described at different levels of analysis (word, sentence, text). Multiple codes may coexist. This section reviews the characteristics of language disorders associated with congenital brain defects or acquired brain conditions. The information is organized in a taxonomy (Figure 1) that (reading from left to right) shows language representation level, functional domain, example of functional domain, and representative clinical deficit. Pragmatics NIH-PA Author Manuscript Pragmatics is concerned with how speakers use language to effect successful functional communication (Kempson, 1975). Pragmatic linguistic representations are activated, typically in social contexts, to serve intentional purposes (e.g., to give instructions, to mask and/or communicate thought), and to make affective judgments (e.g., to praise, blame, criticize, or empathize). A key issue in pragmatic comprehension, as Stemmer (2008) suggests, is how to compute meaning from something that is not stated, a task that requires distinguishing sentence meaning (the semantic properties of a sentence) and speaker meaning (what the speaker intended to communicate; Noveck & Reboul, 2008). NIH-PA Author Manuscript Intentions—As originally used (Brentano, 1874/1973), intentionality referred to a property of mental states: that of being directed towards something. More recently, intentionality is used as a form of representation for mental categories such as beliefs and desires (Malle, Moses, & Baldwin, 2001), with intentionality being a quality of purposeful actions, and intentions being mental states that represent those actions. Theory of mind, a component of social cognition (Yeates et al., 2007), involves the ability to think about mental states in oneself and others and to use them to understand and predict what other people know and how they will act (Bibby & McDonald, 2005). The term, theory of mind, emphasizes that individuals see themselves and others in terms of mental states—desires, emotions, beliefs, intentions, and other inner experiences—that result in (and from) human action (Wellman, Cross, & Watson, 2001). The primary meaning of some verbs is not an action but an internal state. Mental state verbs (Hall & Nagy, 1986) are a class of words that include know, remember, forget, think, believe, and pretend (Hall & Nagy, 1986; Karttunen, 1971). These words assume some information (presuppositions) and suggest other information (implications; Karttunen, 1971; Kiparsky & Kiparsky, 1970). Speech acts (Searle, 1969) are intentional acts performed by a dialogue participant to express the mutual intentions of a speaker and a listener and to influence the mental state of a participant (Beun, 1994). Children with TBI have deficits in comprehension of mental state verbs (Dennis & Barnes, 2000) and in producing appropriate speech acts (e.g., when asked to produce a statement using the words “pie either have” while looking at a picture of adolescents in a school J Clin Exp Neuropsychol. Author manuscript; available in PMC 2011 March 15. Dennis Page 5 NIH-PA Author Manuscript cafeteria staring at a selection of desserts; Dennis & Barnes, 2000). Adolescents with TBI who perform poorly on a test of theory of mind express few mental state terms in their conversations (Stronach & Turkstra, 2008). Children with early unilateral brain damage have impairments in making pragmatic inferences, with different profiles of deficit occurring depending on lesion laterality (Eisele, Lust, & Aram, 1998). Affect—Pragmatics concerns feelings and judgments, as well as information. The ability to be emotionally deceptive is an important component of pragmatics because it requires the recognition that inner emotional states need not be congruent with emotional expressions (Saarni, 1999). Expressing experienced emotion has been termed emotional expression, in contrast to communicating a socially appropriate emotion, emotive communication (Buck, 1994). NIH-PA Author Manuscript Children with TBI have more difficulty with emotive than with emotional communication. They can identify basic emotions felt by characters in narratives (e.g., they know that a character will feel sad when she is sick), and they can understand why a deceptive emotion might be communicated (e.g., they know that a child’s mother will not allow her to play if aware that she is sick); nevertheless, they are unable to communicate the socially deceptive emotion (e.g., looking happy; Dennis, Barnes, Wilkinson, & Humphreys, 1998). When performing the same task, children with autism, a profound disorder of language and communication, have deficits in both emotional and emotive communication (Dennis, Lockyer, & Lazenby, 2000). Intentional–affective language—Intentions and affect often operate together, as in irony and empathy. Irony has complex social functions. Through the use of the rhetorical functions of praise and blame, irony conveys social messages that include formulating a judgment while muting its evaluative force (Dews & Winner, 1997), muting criticism (Harris & Pexman, 2003), or establishing social distance through a negative assessment of the actions of the hearer (Haverkate, 1990). Empathy is a means of giving comfort or maintaining social connectedness in complex or difficult situations. One might use an empathic lie, for instance, to make someone feel better about a bad haircut (e.g., “Your hair looks really nice like that!”). Children with TBI have difficulty understanding irony and empathy. They do not distinguish between the second-order intentions of irony (to make the hearer feel bad about himself or herself) and empathy (to make the hearer feel good about himself or herself; Dennis, Purvis, Barnes, Wilkinson, & Winner, 2001). NIH-PA Author Manuscript Syntax Syntactic structures assign important aspects of sentence meaning (Caplan & Hildebrandt, 1988), especially of functional roles (e.g., who is acting, who is being acted on). Failure to assign and interpret syntactic structure signals a syntactic comprehension disorder (Caramazza & Zurif, 1976), the hallmark of which is an inability to assign aspects of sentence meaning correctly in sentences that are logically and pragmatically semantically reversible except for syntactic structure (e.g., the dog chased the cat/the cat chased the dog). Of patients with syntactic comprehension deficits, some are able to construct relevant syntactic structures even when they fail to map the products to establish meaning (e.g., Linebarger, 1990). Syntactic arguments—The adult neurobiology of syntax suggests left lateralization. The adult left hemisphere has a strong association with syntax; functionally, it constructs syntax in real time (Swinney, Zurif, Prather, & Love, 1996) and assigns syntactic structure during J Clin Exp Neuropsychol. Author manuscript; available in PMC 2011 March 15. Dennis Page 6 NIH-PA Author Manuscript language comprehension (Caplan, 1992; Caplan & Hildebrandt, 1988; Stromswold, Caplan, Alpert, & Rauch, 1996). Damage to perisylvian areas of the left hemisphere disrupts syntax; conversely, left hemisphere damage that spares this region and disrupts lexical–semantic function preserves sensitivity to syntax (Dogil, Haider, Husmann, & Schaner-Wolles, 1995). The immature left hemisphere also has a strong association with syntax. Compared to those with early right hemisphere damage and hemispherectomy, individuals with congenital damage to and removal of the left hemisphere are slower and less accurate in understanding sentences with noncanonical word orders (e.g., reversible passive sentences such as the dog is chased by the cat) in which meaning is provided by syntactic structure but not semantic plausibility, whether comparisons are made between hemidecorticate groups with early lateralized hemispheric damage from varying pathologies (Dennis & Kohn, 1975) or from a single pathology (Dennis & Whitaker, 1976). The syntactic comprehension deficit after left hemisphere damage is evident whether comparisons are made to chronological age (Aram, Ekelman, Rose, & Whitaker, 1985; Dennis, 1980a; Dennis & Kohn, 1975; Dennis & Whitaker, 1976; Paquier & Van Dongen, 1993), mental age (Stark, Bleile, Brandt, Freeman, & Vining, 1995), or brain-intact cotwins (Feldman, Holland, & Keefe, 1989; Hetherington & Dennis, 2004). NIH-PA Author Manuscript Syntactic comprehension deficits for noncanonical word orders are also evident when only part of the left hemisphere is removed but speech control has shifted to the right hemisphere (Kohn, 1980). These data are in agreement with functional magnetic resonance imaging (fMRI) demonstrations that language reorganization after hemispherectomy in childhood involves right hemisphere homologues of the left hemisphere language areas (Liégeois, Connelly, Baldeweg, & Vargha-Khadem, 2008) and also with data showing that congenital left hemisphere focal lesions prompt a mirror-image reorganization of the entire cerebrocerebellar network engaged in speech production (Lidzba, Wilke, Staudt, KrägelohMann, & Grodd, 2008). Semantics Broadly, semantics is concerned with meaning. Semantic disorders in children with brain injury range from severe verbal auditory agnosia for common sounds, such as a dog barking or a doorbell ringing (Cooper & Ferry, 1978), to problems understanding word meaning (Dennis, 1992) or oral or written texts (Barnes, Faulkner, Wilkinson, & Dennis, 2004). Lexicon—The lexicon consists of a word store, most of it concerned with literal meanings of individual words. The lexicon also involves phrasally stipulated meanings of overlearned figurative expressions, such as common idioms. NIH-PA Author Manuscript Literal meaning: According to standard models of speech production (Levelt, 1989), producing semantically appropriate words requires accessing word forms as well as word– sound planning so that the representation of the sound of a word may be converted into a form suitable for production. Disorders of lexis are common in both adults (Libben, 2008) and children with brain injury. Impairments in accessing word forms from concepts are exhibited by failure to produce a word in response to a picture, definition, or context, despite intact semantic and phonological processing evidenced by the ability to describe, categorize, or repeat the target word. A variety of forms of childhood brain injury are associated with word-finding difficulties in which children can produce a word in response to a picture, although not to semantic information such as “What lives in the jungle, has big floppy ears and a trunk?” (Dennis, 1992). Indications of a disorder in accessing word forms include pauses, sequences of sounds that do not form words (neologisms), words related in meaning to the target J Clin Exp Neuropsychol. Author manuscript; available in PMC 2011 March 15. Dennis Page 7 NIH-PA Author Manuscript (semantic paraphasias), and the use of circumlocutions. In the fluent form of childhood aphasia, associated with lesions to the posterior left hemisphere cortical language areas (Klein, Masur, Farber, Shinnar, & Rapin, 1992), anomia, word-finding deficits, semantic paraphasias, and circumlocutions occur (Dennis, 1980b; Hynd et al., 1995). Children with aphasia from TBI exhibit a variety of language symptoms in the acute stage, which show some resolution over time (Loonen & Van Dongen, 1990; Van Dongen & Loonen, 1977), even though anomia and reduced verbal fluency are consistent long-term deficits (Hécaen, 1983; Jordan & Murdoch, 1993; Jordan, Ozanne, & Murdoch, 1988, 1990). The adult aphasia literature includes an extensive series of report of category-specific semantic disorders, with reports of selective semantic impairment of particular concepts, such as those related to animate things and food compared to man-made objects (e.g., Sartori & Job, 1988). Interpretation of category-specific naming deficits is still controversial (see Mahon & Caramazza, 2009; Martin & Caramazza, 2003). Modality-specific anomia has been described in children (e.g., Dennis, 1976). Reading and spelling may be relatively preserved with cortical lesions in the left-hemispheric posterior language areas in children with anomia (Dennis, 1980b; Hynd et al., 1995). Further, a child with anomia from stroke was able to perform tactile–visual matches of misnamed objects (Dennis, 1980b). These data suggest a problem between modality-specific semantic systems and the activation of auditory word forms. NIH-PA Author Manuscript Literal meaning has been studied by analysis of symptoms of fluent adult aphasia, such as logorrhea, verbal stereotypies, perseverations, neologisms, jargon, and paraphasias, which were once thought to be rare in children (Alajouanine & Lhermitte, 1965). Aphasic symptoms in children have proved to be quite varied (Van Hout, 1991), with a number of adult aphasic syndromes being described in children: jargon aphasia (Visch-Brink & Van de Sandt-Koenderman, 1984; Woods & Teuber, 1978); Wernicke’s aphasia and transcortical sensory aphasia (Van Hout, Evrard, & Lyon, 1985); conduction aphasia (Van Dongen, Loonen, & Van Dongen, 1985); transcortical sensory aphasia (Cranberg, Filley, Hart, & Alexander, 1987; Van Dongen & Paquier, 1991); anomic aphasia (Hynd, Semrud-Clikeman, Lorys, Novey, & Eliopulos, 1990); and alexia without agraphia (Makino et al., 1988; Paquier et al., 1989). To be sure, adult aphasic syndromes observed in children occur with different base frequencies (Rapin, 1995). NIH-PA Author Manuscript Figurative meaning: Idioms are nonliteral phrases (e.g., kick the bucket) whose figurative meanings (here, to die) cannot be derived from the literal meanings of their individual words (here, kick and bucket). Idioms are ubiquitous (Brinton, Fujiki, & Mackey, 1985) in conversational (approximately four figures of speech occur in each minute of conversation; Pollio, Barlow, Fine, & Pollio, 1977) and instructional language (Lazar, Warr-Leeper, Nicholson, & Johnson, 1989). Studies of figurative language have identified two types of idiom: one processed like literal language, the other requiring semantic decomposition. Nondecomposable idioms (e.g., kick the bucket) are learned and represented in the mental lexicon as units; being syntactically and lexically inflexible, they depend on context for interpretation (Gibbs, 1991). Children with SBM have difficulty understanding idioms, even when they can understand the individual words in the idiom. Of interest, they are better able to understand idioms whose meaning can be derived from the individual words (e.g., “talk a mile a minute”) than nondecomposable idioms that require them to integrate the words and the context (HuberOkrainec, Blaser, & Dennis, 2005). Their relatively well-preserved syntax and grammar skills for literal language (Dennis, Hendrick, Hoffman, & Humphreys, 1987) may facilitate the semantic compositional analysis of decomposable, but not nondecomposable, idioms. J Clin Exp Neuropsychol. Author manuscript; available in PMC 2011 March 15. Dennis Page 8 NIH-PA Author Manuscript The neurobiology of idioms may involve a distributed neural system. For children with SBM, variability in idiom comprehension is related to the integrity of the corpus callosum (Huber-Okrainec et al., 2005). Text—The derivation of meaning in oral or written texts involves complex (van Dijk & Kintsch, 1983) inferencing and integration among a text representation built on current words and sentences, prior context, and world knowledge (Perfetti & Frishkoff, 2008). The flow of topics, narrative script, and the plotline form the schematic structure. The text macrostructure concerns the relations among sentences sharing a topic, and deficits in macrostructure are usually manifest as failures of text coherence. Text microstructure concerns local sentential relations, and these are usually manifest as failure of text cohesion. Schematic structure: Problems in schematic structure are not uncommon in children with brain injury. Both children with TBI and children with hydrocephalus, most with SBM, have deficits in producing and understanding social scripts (Chapman et al., 1992; Dennis & Barnes, 1990). NIH-PA Author Manuscript Macrostructure and microstructure: Problems in text macrostructure are also common in children with brain injury. In telling stories, children with hydrocephalus, most with SBM, produce poorly coherent narratives that are difficult to process, unclear, and uneconomic (Dennis, Jacennik, & Barnes, 1994). Children with TBI also have problems in discourse macrostructure (Chapman et al., 2004; Ewing-Cobbs, Brookshire, Scott, & Fletcher, 1998). Problems in text microstructure have been identified in children with CNS injury. Children with left hemi-decortication for congenital left hemisphere damage have impaired referential cohesion in texts, failing to sustain a chain of anaphoric reference (Lovett, Dennis, & Newman, 1986). Children with early focal brain injury also show impairments in referential cohesion (Reilly, Bates, & Marchman, 1998). Compared to controls, the narratives of children with hydrocephalus, most with SBM, include referentially ambiguous material (Dennis et al., 1994). Inferencing—Text meaning is constructed over time, not always literally stated. Text inferences create a text representation, through coherence inferences (integration of semantic knowledge with lexical content to interpret the text) and elaborative inferences (creation of a mental model of the situation the text describes; Morrow, Bower, & Greenspan, 1990; Whitney, 1987; Zwaan, Langston, & Graesser, 1995). Children with TBI make coherence but not elaborative inferences (Barnes & Dennis, 2001; Dennis & Barnes, 2001). NIH-PA Author Manuscript Text inferences: Text-based representations denote the literal meaning of the text and are constructed through integration of information in the text and revision of information in relation to the unfolding context (Clifton & Duffy, 2001; Kintsch, 1988; Schmalhofer, McDaniel, & Keefe, 2002). Integration is effected through processes such as pronominal reference, which links characters, objects, and events with their referent pronouns, and by bridging inferences, which integrate ideas or sentences explicitly stated within a text. Initially, word meanings are passively activated without respect to the context; typically, more semantic information is activated than will be required to represent the text (Schmalhofer et al., 2002). As text becomes integrated, contextually irrelevant meanings are suppressed or their activation is not sustained, and appropriate meanings are enhanced (Gernsbacher, 1990; Gernsbacher & Faust, 1991). For example, in order to interpret the sentence, “Jim picked up the spade,” the reader may retrieve information from earlier in the text about Jim helping his mother in the garden. Children and adolescents with hydrocephalus, most with SBM, have difficulty integrating propositions within texts, take J Clin Exp Neuropsychol. Author manuscript; available in PMC 2011 March 15. Dennis Page 9 NIH-PA Author Manuscript longer to integrate information over larger chunks of text, continue to show substantial interference effects in ambiguity resolution tasks beyond the point at which their peers have suppressed contextually irrelevant meanings, and are less efficient in constructing a coherent and integrated text base (Barnes et al., 2004). Knowledge-based inferences: The online working model of text meaning includes realworld knowledge and goals, such as inferences about space, time, causality, and the goals of the characters (Kintsch, 1988; Schmalhofer et al., 2002; Zwaan & Radvansky, 1998). Constructing situation models requires knowledge-based inferences, which we have studied in typical (Barnes, Dennis, & Haefele-Kalvaitis, 1996) and atypical (Barnes & Dennis, 1996, 2001; Cain, Oakhill, Barnes, & Bryant, 2001) development, using a paradigm in which children learn a new knowledge base about a make-believe world and then integrate new knowledge with events in the text. Children with hydrocephalus, most with SBM, make fewer knowledge-based inferences than controls (Barnes & Dennis, 1998). Differences with same-age peers are magnified when the processing load is high (i.e., when inferences have to be made by retrieving knowledge from memory as stories unfold in time), and the differences are attenuated when the processing load is low (i.e., when they are cued with the knowledge needed to make an inference; e.g., Barnes & Dennis, 2001; Cain et al., 2001). NIH-PA Author Manuscript Text-based comprehension—Text meaning is continuously and actively constructed through a series of online comprehension processes that operate at the word, sentence, and text levels, and which draw on cognitive resources such as working memory. In a recent model of meaning comprehension (Barnes, Huber, Johnson, & Dennis, 2007) we have proposed that meaning involves a surface code, a text base, and a situation model, the last two supported by an integration and revision buffer fueled by WM and inhibitory control. The surface code directly activates old meanings stored in memory. Online iterative cycles of integration and revision facilitate the construction of new meaning. Models of comprehension distinguish between automatic activation of surface codes (the passive activation of meaning from stored lexical representations; Clifton & Duffy, 2001) and resource-intensive construction and revision of text-based representations and situation models. Children with SBM can construct text-based representations when the demands on integration and revision are relatively low, but not when significant revision processes are required. They seem unable to integrate across sentences to update and revise situation models. They also have difficulty constructing situation models by integrating text and world knowledge to understand ongoing narratives. Phonology NIH-PA Author Manuscript The segmental aspect of phonology and speech processing involves phonological perception and integration (Plante, Holland, & Schmithorst, 2006) of features such as vowels, consonants, and syllables that have direct, identifying relationships with utterances (Crystal, 1973). The nonsegmental aspect of phonology concerns a range of features, loosely referred to as “tone of voice,” that include intonation, stress, rhythm, and speed of speaking and that have a variable relation to the segmental, verbal aspects of utterances (Crystal, 1973). Segmentals—Disorders of phonological processing commonly follow both adult (Buckingham & Christman, 2008) and child brain injury (Aram & Nation, 1982). Impairments in word–sound planning are demonstrated by substitutions involving phonemes with dissimilar distinctive features and/or omissions and misordering of phonemes (phonemic paraphasias). Brain-injured children’s word-finding errors include phonemic paraphasias, phonemic jargon, and neologisms (Dennis, 1980b; Van Dongen & Paquier, 1991; Visch-Brink & Van de Sandt-Koenderman, 1984). Phonological-processing deficits J Clin Exp Neuropsychol. Author manuscript; available in PMC 2011 March 15. Dennis Page 10 NIH-PA Author Manuscript are among the language and reading impairments reported in children who have sustained left hemisphere strokes in middle childhood (Dennis, 1980b; Pitchford, 2000). Compared to his cotwin, a child with a left hemisphere stroke in middle childhood regained phonological skills lost at the time of the stroke, although he failed to acquire new phonological skills (Hetherington & Dennis, 2004). Phonological compromise is often considered the core deficit in developmental dyslexia (Lyon, 1995). Structural and functional neuroimaging studies of normal readers and individuals with dyslexia have demonstrated the engagement of left hemisphere structures in both reading and phonological processing (e.g., Pugh et al., 2000; Simos, Breier, Fletcher, Bergman, & Papanicolaou, 2000). NIH-PA Author Manuscript Suprasegmentals—Prosody, or suprasegmental information, cues both emotional state (emotional prosody, including the emotional state of the speaker) and language structure, including sentence type (e.g., whether question or statement), the occurrence of phrasal units within sentences, and boundaries or words within phrases (Plante et al., 2006). Disturbances in emotional prosody have been observed in adults with brain injury (Van Lancker-Sidtis, 2008) and in children with severe TBI (Hattiangadi et al., 2005). In terms of neurobiology, prosodic disturbances have been observed in children with right hemisphere dysfunction (Cohen, Branch, & Hynd, 1994) and young adults with congenital agenesis of the corpus callosum (Paul, Van Lancker-Sidtis, Schieffer, Dietrich, & Brown, 2003). Morphology Morphology is critical to the production of complex words (Jarema, 2008), and components of the language production system are important for producing free-standing function words and inflectional morphemes in words and sentences. These morphological components are different from vocabulary words because they do not bear nonemphatic stress in derived words or sentence structures, and they do not follow regular word formation processes. The speech of adult aphasic patients with anterior lesions is often agrammatic, with a breakdown of sentence structure and the omission or misuse of grammatical morphemes, even while access to content words, such as verbs and nouns, is relatively unimpaired. In adults, a disturbance affecting the production of inflections and derivational morphemes has been termed agrammatism or paragrammatism, and the characteristic is the omission or substitution of function words and affixes (Menn, Obler, & Goodglass, 1990). NIH-PA Author Manuscript The neurobiology of morphology suggests some hemispheric lateralization in some cases of childhood CNS damage. Curtiss and Schaeffer (1997) analyzed the language of children with hemispherectomy with respect to the inflectional (I) system and its subcategories tense, subject agreement, and object agreement. Compared to those with right hemispherectomy, children with left hemispherectomy use a restricted range and number of I-system morphemes and have particular problem with auxiliaries, despite intact syntactic and morphological structures of other types (Curtiss & Schaeffer, 1997). Children with left hemispherectomy also have particular problems producing tag questions, which involve inflectional morphology (Dennis & Whitaker, 1976), and deficits that occur in some adults with paragrammatism. These data suggest a high level of vulnerability of the inflectional system to developmental, childhood-acquired, and adult-acquired language pathology. Speech production Phonetics—Phonetic deficits, termed developmental apraxia of speech or developmental verbal dyspraxia, involve difficulty in coordinating voluntary movements of the speech articulation mechanism (Aram & Nation, 1982; Shriberg, Aram, & Kwiatkowski, 1997a, 1997b). They are a neurological childhood speech sound disorder in which the precision and J Clin Exp Neuropsychol. Author manuscript; available in PMC 2011 March 15. Dennis Page 11 NIH-PA Author Manuscript consistency of speech movements are impaired in the absence of neuromuscular deficits such as abnormal reflexes. They may occur from known neurological impairment or as an idiopathic speech sound disorder, and the core impairment is in planning and/or programming the spatiotemporal parameters of movement sequences that result in errors of speech sound production and speech prosody (American Speech-Language-Hearing Association, 2007). They may co-occur with language disorders and/or speech fluency disorders, described below. Motor speech—Congenital malformations of the cerebellum are associated with a form of ataxic dysarthria, which is a motor speech deficit involving dysfluency, ataxic dysarthria (articulatory inaccuracy, prosodic excess, and phonatory–prosodic insufficiency), and slowed speech rate (Brown, Darley, & Aronson, 1970; Darley, Aronson, & Brown, 1969). The narratives of both children and young adults with SBM are characterized by all three motor speech deficits (Huber-Okrainec, Dennis, Brettschneider, & Spiegler, 2002). A range of acquired CNS insults in children result in mutism, often resolving to ataxic dysarthria, and termed mutism with subsequent dysarthria (MSD). There is an initial period of mutism in herpes simplex encephalitis (Paquier & Van Dongen, 1991; Van Hout et al., 1985), and mutism has also been described in children treated for cancer (Hudson et al., 1990) and children with anoxic encephalopathy (Cooper & Flowers, 1987). NIH-PA Author Manuscript The most fully studied form of MSD is the one identified in children treated for posterior fossa tumors, who acutely or progressively lose previously acquired language skills (Dailey, McKhann, & Berger, 1995; Di Cataldo et al., 2001; Doxey, Bruce, Sklar, Swift, & Shapiro, 1999; Humphreys, 1989; Rekate, Grubb, Aram, Hahn, & Ratcheson, 1985; Van Dongen, Catsman-Berrevoets, & van Mourik, 1994). Nearly all MSD patients are less than 10 years of age, and the condition has been described in children as young as age 2 (Van Dongen et al., 1994). The MSD syndrome involves a complete but transient loss of speech, resolving into a dysarthria with imprecise consonants, articulatory breakdowns, prolonged phonemes, prolonged intervals, slow rate of speech, lack of volume control, harsh voice, pitch breaks, variable pitch, and explosive onset (Hudson, Murdoch, & Ozanne, 1989; van Mourik, Catsman-Berrevoets, Yousef-Bak, Paquier, & Van Dongen, 1998). Improvement of the dysarthria to normal speech seems to be related to the recovery of complex movements of the mouth and tongue (Van Dongen et al., 1994). NIH-PA Author Manuscript Long-term recovery of the ataxic dysarthria is incomplete. Very-long-term survivors of childhood cerebellar tumors continue to show ataxic dysarthric features in their spontaneous speech (Huber, Dennis, Bradley, & Spiegler, 2007); further, tumor survivors with a history of MSD show more ataxic dysarthria than those without MSD at the time of tumor treatment (Huber-Okrainec, Dennis, Bradley, & Spiegler, 2006). Because mutism has been most commonly associated with cerebellar tumors, its neurobiology has been fairly well studied. Mutism has been associated with posterior fossa tumors located in the midline or vermis of the cerebellum and with tumors that invade the cerebellar hemispheres or the deep nuclei of the cerebellum (Humphreys, 1989; Rekate et al., 1985) and brainstem (Doxey et al., 1999; van Mourik et al., 1998). Children with postoperative mutism show brainstem compression, which may represent white matter injury (McMillan et al., 2009). It has been proposed that the mutism of MSD is related to bilateral involvement of the dentate nuclei, and, further, that the subsequent dysarthric speech represents a recovering cerebellar mechanism (Ammirati, Mirzai, & Samii, 1989). J Clin Exp Neuropsychol. Author manuscript; available in PMC 2011 March 15. Dennis Page 12 LANGUAGE AND OTHER COGNITIVE SYSTEMS NIH-PA Author Manuscript Language does not exist in isolation. Both comprehension and production of language are grounded in the motor system. Language is related to general-purpose brain memory systems and is instantiated by cognitive resources such as working memory and inhibitory control. Language as embodied action NIH-PA Author Manuscript Earlier views of language assumed it to have conceptual content that was more abstract than information in sensory and motor systems. More recently, however, the embodied cognition framework has argued that conceptual content is grounded in basic sensory and motor processes (e.g., Gallese & Lakoff, 2005; Zwaan, 2004). Current theoretical accounts of language as embodied action (Fernandino & Iacoboni, in press; Fischer & Zwaan, 2008) are unraveling the interaction between the brain’s systems of language and action for both production and comprehension (reviewed in Zwaan, Taylor, & de Boer, in press). For example, verbs describing actions activate areas of the motor cortex that are also active when the action is performed. Verbs referring to hand actions activate the hand area of the motor strip, verbs referring to leg actions the more dorsal leg area, and verbs denoting mouth actions the mouth area (Hauk, Johnsrude, & Pulvermüller, 2004; but see Kemmerer, Gonzalez Castillo, Talavage, Patterson, & Wiley, 2008, who found somatotopic activation for hand and leg verbs, but not for mouth verbs). Similar effects have been reported in neuroimaging studies of sentence comprehension (Aziz-Zadeh, Wilson, Rizzolatti, & Iacobini, 2006; Tettamanti et al., 2005). Consistent with this, behavioral evidence suggests motor involvement in language comprehension (e.g., lexical stimuli have been shown to momentarily affect hand aperture in a reaching-to-grasp task; Gentilucci & Gangitano, 1998; Glover, Rosenbaum, Graham, & Dixon, 2004). Similarly, hand–arm actions are influenced by sensibility judgments about sentences (e.g., Glenberg & Kaschak, 2002; Zwaan & Taylor, 2006). General purpose systems NIH-PA Author Manuscript It has been proposed (Ullman, 2008; Ullman et al., 1997) that lexical information depends on declarative memory (specialized for arbitrary associations and grounded in temporal lobe structures) while grammar relies on procedural memory (specialized for rules and sequences and rooted in frontal and basal ganglia structures). The argument is that, given that word forms are like facts in being arbitrary, the declarative memory system may subserve words as well as facts and events, and, given that rules are like skills in requiring the coordination of procedures in real time, the procedural memory system may process grammatical rules as well as motor and perceptual skills. Support for this proposal has come from several sources. Although there are different views about whether regular and irregular past tense forms of verbs are both computed by rules (Chomsky & Halle, 1968) or memory (MacWhinney & Leinbach, 1991), Ni et al. (2000) hypothesized that irregular past tense verb forms are memorized, while regular forms (verb stem +ed) are generated by a rule that comprises two operations: copying the stem and adding a suffix. Patients with impaired declarative memory (Alzheimer’s disease) or lexical memory (posterior aphasia) were found to overgeneralize the past tense suffix and to have more difficulty converting irregular verbs to past tense forms than they did converting regular or novel verbs. Patients with procedural impairments and damage to the frontal-basal ganglia system (Parkinson’s disease) or with agrammatism (anterior aphasia) showed the opposite pattern. In a fMRI paradigm, form errors (e.g., “Trees can grew”) triggered increased activation in the left inferior frontal area (Broca’s area), whereas meaning anomalies (e.g., “Trees can eat”) resulted in superior temporal and middle and superior frontal activation (Ni et al., 2000). J Clin Exp Neuropsychol. Author manuscript; available in PMC 2011 March 15. Dennis Page 13 NIH-PA Author Manuscript The broad dissociation between form and procedural memory, on the one hand, and meaning and semantic memory, on the other, is evident in children with brain injury. Despite a range of cognitive and language problems in the semantic and pragmatic domains (Fletcher, Barnes, & Dennis, 2002), children with SBM have intact procedural learning and memory (Edelstein et al., 2004), as well as relatively intact ability to assign thematic roles in syntactic comprehension tasks (Dennis et al., 1987). This dissociation is also demonstrable after childhood-acquired brain injury. Comparing language recovery in 13-year-old identical twins, one of which had sustained a left hemisphere arteritic stroke at age 7 (Hetherington & Dennis, 2004), we reported that the twin with the stroke showed full recovery of semantic memory and word production, but had persisting impairments in tag question production and the ability to assign thematic roles in syntactic comprehension tasks. Considered together, a group of studies suggest an association between the procedural system and grammar and a dissociation between the procedural system and semantics within a form of congenital brain injury and, further, an association between recovery of semantic memory and word finding and a dissociation between recovery of semantic memory and the persistence of syntactic impairments in childhood-acquired stroke. Processing resources NIH-PA Author Manuscript Language comprehension is constrained by processing resources. WM is the process by which information is temporarily activated in memory for rapid manipulation and retrieval. Inhibitory control is the ability to stop or modulate ongoing actions or to switch between competing representations. In adults, verbal WM capacity is related to language comprehension (Caplan & Waters, 2006), and, in children, WM efficiency is linked to a range of language, learning, and academic competencies (e.g., Bull & Scerif, 2001). Both WM and inhibitory control have a resource-limited capacity (Gazzaley, Cooney, McEvoy, Knight, & D’Esposito, 2005), so WM involves the activation of information, and inhibitory control keeps irrelevant information out of WM (Dempster, 1993; Engle, Conway, Tuholski, & Shisler, 1995; Harnishfeger & Bjorklund, 1994) through processes like suppression. Working memory—Understanding sentences and texts is subject to capacity constraints, and text comprehension requires active memory for meaning construction (Clifton & Duffy, 2001; van den Broek, Young, Tzeng, & Linderholm, 1999). Because texts extend over time, with semantic representations being iteratively modified by reactivating old information and linking it with incoming information, working memory is a capacity component of many language comprehension models (e.g., Kintsch, 1988; van den Broek et al., 1999). NIH-PA Author Manuscript Capacity constraints limit comprehension in children with language disorders. Sentence and text comprehension is impaired in SBM (e.g., Dennis & Barnes, 1993), with comprehension deficits being driven, at least in part, by capacity limitations related to integrating meaning over longer text segments (Barnes et al., 2004). WM links semantic information and its source and integrates distant information across text segments, and WM limitations are associated with poor text comprehension. WM is a source of syntactic comprehension disorder (Caplan & Hildebrandt, 1988). One source is a specific disturbance with functional argument structure and difficulties with noncanonical orders of sentence constituents, possibly because of defective representations or procedures for handling the traces of moved semantic roles in sentences like passives and object relatives with noncanonical word orders (Berndt, Mitchum, & Wayland, 1997). Another source is a reduction in the computational resources for syntactic comprehension (Caplan, Waters, DeDe, Michaud, & Reddy, 2007). For example, the poor formation of syntax in adult Broca’s aphasia occurs not because of insufficient knowledge of syntactic J Clin Exp Neuropsychol. Author manuscript; available in PMC 2011 March 15. Dennis Page 14 dependencies, but because of failure of real-time implementation of these specific representations (Love, Swinney, Walenski, & Zurif, 2008). NIH-PA Author Manuscript Individuals with hemispherectomy for early left hemisphere injury have a combined impairment. They are insensitive to the role of function words that cue syntactic structure, even on metacognitive tasks with no time constraints (Dennis, 1980a), which suggests that they have trouble constructing functional argument structures. In addition, they are slower to respond correctly to noncanonical sentences, and they make fewer errors when they respond slowly (Dennis & Kohn, 1975), which suggests some limitation in WM resources, with performance deficits becoming attenuated when more WM resources are allocated to the task. NIH-PA Author Manuscript Inhibitory control: Activation and suppression—Inhibitory control may be automatic or effortful (Friedman & Miyake, 2004). Automatic inhibitory control, such as the ability to avoid returning gaze to a previously explored location, develops in infancy or early in childhood (Richards, 2003). Effortful forms of inhibitory control, involving the ability to stop performing automatic or routine behaviors when they become undesirable due to changing circumstances or to altered intentions, have the more protracted development (Band, van der Molen, Overtoom, & Verbaten, 2000; Harnishfeger & Pope, 1996; Houghton & Tipper, 1994; Pascual-Leone, 2001; Williams, Ponesse, Schachar, Logan, & Tannock, 1999). One form of effortful inhibition (Kipp, 2005) involves the maintenance of competing cognitive representations and the successive activation and suppression of irrelevant representations (Perner, Lang, & Kloo, 2002). Suppression is that aspect of inhibitory control preventing no-longer-relevant information from remaining activated. Suppression is an active process, not simply a passive decay, and one that is driven by top-down semantic representations (Gernsbacher, 1995). Suppression uses mental resources; for example, the inhibition of inappropriate lexical interpretations puts demands on cognitive processes (Tompkins, Lehman-Blake, Baumgaertner, & Fassbinder, 2002). NIH-PA Author Manuscript Children with hydrocephalus, most with SBM, fail to suppress contextually irrelevant meaning, which is associated with poor text comprehension (Barnes et al., 2004), in agreement with the findings in adults that active suppression is important for both literal and figurative language comprehension (Gernsbacher & Faust, 1991; Gernsbacher & Robertson, 1999). Deficient suppression may not only preempt other comprehension processing resources, but also provide incomplete input to mental computations that generate a wellspecific semantic representation (Tompkins et al., 2002). Children with SBM have poorly specified semantic representations that contain extraneous, contextually irrelevant information, which may explain the long-standing observation (Taylor, 1961) that their conversational language is referentially underspecified and tangential. The consequences of impaired semantic representation are considerable. Semantic representations may be well specified or underspecified, the latter form of shallow parsing being sufficient for some tasks, such as generating an index or chatting at a cocktail party, although not for others, such as providing or understanding specific instructions, communicating referentially detailed information, or academic learning (Sanford & Sturt, 2002). CODA Children exhibit a range of language disorders after acquired or congenital brain injury. Language breakdown may occur at the level of pragmatics, syntax, semantics, phonology, morphology, or speech production. While earlier views of language considered it in relative isolation, current views highlight how language is grounded in motor functions, is part of J Clin Exp Neuropsychol. Author manuscript; available in PMC 2011 March 15. Dennis Page 15 NIH-PA Author Manuscript general-purpose cognitive systems, and relies on domain-general resources. Much is yet to be understood about the neurobiology of language disorders following CNS injury, but even more remains to be discovered about how language disorders engage with movement and cognition. Acknowledgments Preparation of this paper was supported in part by National Institute of Child Health and Human Development Grants P01 HD35946 and P01 HD35946–06, “Spina Bifida: Cognitive and Neurobiological Variability,” by National Institute of Neurological Diseases and Stroke Grant 2R01NS 21889–16, “Neurobehavioral Outcome of Head Injury in Children,” and by National Institutes of Health Grant 1RO1 HD04946, “Social Outcomes in Pediatric Traumatic Brain Injury.” I thank Arianna Stefanatos for assistance with manuscript preparation. References NIH-PA Author Manuscript NIH-PA Author Manuscript Alajouanine T, Lhermitte F. Acquired aphasia in children. Brain 1965;88:653–662. [PubMed: 5856072] American Speech-Language-Hearing Association. Childhood apraxia of speech. 2007. (Tech. Rep.). Retrieved August 27, 2009, from http://www.asha.org/policy Ammirati M, Mirzai S, Samii M. Transient mutism following removal of a cerebellar tumor. A case report and review of the literature. Child’s Nervous System 1989;5:12–14. Anderson, VA.; Taylor, HG. Meningitis. In: Yeates, KO.; Ris, MD.; Taylor, HG., editors. Pediatric neuropsychology: Research, theory, and practice. New York: Guilford Press; 2000. p. 117-148. Appleton RE. The Landau–Kleffner syndrome. Archives of Disease in Childhood 1995;72:386–387. [PubMed: 7542439] Aram DM, Ekelman BL, Rose DF, Whitaker HA. Verbal and cognitive sequelae following unilateral lesions acquired in early childhood. Journal of Clinical and Experimental Neuropsychology 1985;7:55–78. [PubMed: 3980681] Aram, DM.; Nation, JE. Child language disorders. St Louis, MO: C. V. Mosby; 1982. Aziz-Zadeh L, Wilson SM, Rizzolatti G, Iacoboni M. Congruent embodied representations for visually presented actions and linguistic phrases describing actions. Current Biology 2006;16:1818–1823. [PubMed: 16979559] Band GPH, van der Molen MW, Overtoom CCE, Verbaten MN. Ability to activate and inhibit speeded responses: Separate developmental trends. Journal of Experimental Child Psychology 2000;75:263– 290. [PubMed: 10698613] Barnes, MA.; Dennis, M. Reading comprehension deficits arise from diverse sources: Evidence from readers with and without developmental brain pathology. In: Cornoldi, C.; Oakhill, J., editors. Reading comprehension difficulties: Processes and intervention. Mahwah, NJ: Lawrence Erlbaum Associates, Inc; 1996. p. 251-278. Barnes MA, Dennis M. Discourse after early-onset hydrocephalus: Core deficits in children of average intelligence. Brain and Language 1998;61:309–334. [PubMed: 9570868] Barnes MA, Dennis M. Knowledge-based inferencing after childhood head injury. Brain and Language 2001;76:253–265. [PubMed: 11247644] Barnes MA, Dennis M, Haefele-Kalvaitis J. The effects of knowledge availability and knowledge accessibility on coherence and elaborative inferencing in children from six to fifteen years of age. Journal of Experimental Child Psychology 1996;61:216–241. [PubMed: 8636665] Barnes MA, Faulkner H, Wilkinson M, Dennis M. Meaning construction and integration in children with hydrocephalus. Brain and Language 2004;89:47–56. [PubMed: 15010236] Barnes MA, Huber J, Johnston AM, Dennis M. A model of comprehension in spina bifida myelomeningomyelocele: Meaning activation, integration and revision. Journal of the International Neuropsychological Society 2007;13:854–864. [PubMed: 17697417] Bates, E.; Thal, D.; Janowsky, JS. Early language development and its neural correlates. In: Segalowitz, S.; Rapin, I., editors. Handbook of neuropsychology: Vol. 7. Child neuropsychology. Amsterdam: Elsevier; 1992. p. 69-110. J Clin Exp Neuropsychol. Author manuscript; available in PMC 2011 March 15. Dennis Page 16 NIH-PA Author Manuscript NIH-PA Author Manuscript NIH-PA Author Manuscript Bates, E.; Vicari, S.; Trauner, D. Neural mediation of language development: Perspectives from lesion studies of infants and children. In: Tager-Flusberg, H., editor. Neurodevelopmental disorders: Contributions to a new framework from the cognitive neurosciences. Cambridge, MA: MIT Press; 1999. p. 533-581. Berndt RS, Mitchum CC, Wayland S. Patterns of sentence comprehension in aphasia: A consideration of three hypotheses. Brain and Language 1997;60:197–221. [PubMed: 9344477] Beun RJ. Mental state recognition and communicative effects. Journal of Pragmatics 1994;21:191– 214. Bibby H, McDonald S. Theory of mind after traumatic brain injury. Neuropsychologia 2005;43:99– 114. [PubMed: 15488910] Brentano, F. Psychology from an empirical standpoint. New York: Humanities Press; 1973. (Original work published 1874) Brinton B, Fujiki M, Mackey TA. Elementary school-age children’s comprehension of specific idiomatic expressions. Journal of Communication Disorders 1985;18:245–257. [PubMed: 4019816] Brown JR, Darley FL, Aronson AE. Ataxic dysarthria. International Journal of Neurology 1970;7:302– 318. [PubMed: 5499525] Buck R. The neuropsychology of communication: Spontaneous and symbolic aspects. Journal of Pragmatics 1994;22:265–278. Buckingham, HW.; Christman, SS. Disorders of phonetics and phonology. In: Stemmer, B.; Whitaker, HA., editors. Handbook of the neuroscience of language. New York: Elsevier; 2008. p. 127-136. Bull R, Scerif G. Children’s mathematics ability: Inhibition, switching, & working memory. Developmental Neuropsychology 2001;19:273–293. [PubMed: 11758669] Cain K, Oakhill JV, Barnes MA, Bryant PE. Comprehension skill, inference making ability, and their relation to knowledge. Memory and Cognition 2001;29:850–859. Caplan, D. Language: Structure, processing, and disorders. Cambridge, MA: MIT Press; 1992. Caplan, D.; Hildebrandt, N. Disorders of syntactic comprehension. Cambridge, MA: MIT Press; 1988. Caplan, D.; Waters, G. Language disorders in aging. In: Bialystok, E.; Craik, FIM., editors. Lifespan cognition: Mechanisms of change. New York: Oxford University Press; 2006. p. 253-263. Caplan D, Waters G, DeDe G, Michaud J, Reddy A. A study of syntactic processing in aphasia: I. Behavioral (psycholinguistic) aspects. Brain and Language 2007;101:103–150. [PubMed: 16999989] Caramazza A, Zurif EB. Dissociation of algorithmic and heuristic processes in language comprehension: Evidence from aphasia. Brain and Language 1976;3:572–582. [PubMed: 974731] Chapman SB, Culhane KA, Levin HS, Harward H, Mendelsohn D, Ewing-Cobbs L, et al. Narrative discourse after closed head injury in children and adolescents. Brain and Language 1992;43:42– 65. [PubMed: 1643511] Chapman SB, Sparks G, Levin HS, Dennis M, Roncadin C, Zhang L, et al. Discourse macrolevel processing after severe pediatric traumatic brain injury. Developmental Neuropsychology 2004;25:37–60. [PubMed: 14984328] Chomsky, N.; Halle, M. The sound pattern of English. New York: Harper and Row; 1968. Clifton C, Duffy SA. Sentence and text comprehension: Roles of linguistic structure. Annual Review of Psychology 2001;52:167–196. Cohen MJ, Branch WB, Hynd GW. Receptive prosody in children with left or right hemisphere dysfunction. Brain and Language 1994;47:171–181. [PubMed: 7953612] Cooper JA, Ferry PC. Acquired auditory verbal agnosia and seizures in childhood. Journal of Speech and Hearing Disorders 1978;43:176–184. [PubMed: 96302] Cooper JA, Flowers CR. Children with a history of acquired aphasia: Residual language and academic impairments. Journal of Speech and Hearing Disorders 1987;52:251–262. [PubMed: 2458505] Cranberg LD, Filley CM, Hart EJ, Alexander MP. Acquired aphasia in childhood: Clinical and CT investigations. Neurology 1987;37:1165–1172. [PubMed: 2439948] Crystal D. Non-segmental phonology in language acquisition: A review of the issues. Lingua 1973;32:1–45. J Clin Exp Neuropsychol. Author manuscript; available in PMC 2011 March 15. Dennis Page 17 NIH-PA Author Manuscript NIH-PA Author Manuscript NIH-PA Author Manuscript Curtiss, S.; Schaeffer, J. Syntactic development in children with hemispherectomy: The Infl-System. In: Hughes, E.; Hughes, M.; Greenhill, A., editors. Proceedings of the 21st Annual Boston University Conference on Language Development. Somerville, MA: Cascadilla Press; 1997. p. 103-114. Dailey AT, McKhann GM, Berger MS. The pathophysiology of oral pharyngeal apraxia and mutism following posterior fossa tumor resection in children. Journal of Neurosurgery 1995;83:467–475. [PubMed: 7666224] Darley FL, Aronson AE, Brown JR. Differential diagnostic patterns of dysarthria. Journal of Speech and Hearing Research 1969;12:246–269. [PubMed: 5808852] Del Bigio MR. Neuropathological changes caused by hydrocephalus. Acta Neuropathologica 1993;85:573–585. [PubMed: 8337936] Dempster, FN. Resistance to interference: Developmental changes in a basic processing mechanism. In: Howe, ML.; Pasnak, R., editors. Emerging themes in cognitive development: Vol. 1. Foundations. New York: Springer-Verlag; 1993. p. 3-27. Denes, G. Acquired epileptiform aphasia or Landau–Kleffner syndrome: Clinical and linguistic aspects. In: Stemmer, B.; Whitaker, HA., editors. Handbook of the neuroscience of language. New York: Elsevier; 2008. p. 361-366. Dennis M. Dissociated naming and locating of body parts after left anterior temporal lobe resection: An experimental case study. Brain and Language 1976;3:147–163. [PubMed: 938923] Dennis M. Capacity and strategy for syntactic comprehension after left or right hemidecortication. Brain and Language 1980a;10:287–317. [PubMed: 7407549] Dennis, M. Strokes in childhood: I. Communicative intent, expression, and comprehension after left hemisphere arteriopathy in a right-handed nine-year-old. In: Rieber, R., editor. Language development and aphasia in children. New York: Academic Press; 1980b. p. 45-67. Dennis M. Word finding in children and adolescents with a history of brain injury. Topics in Language Disorders 1992;13:66–82. Dennis M, Barnes MA. Knowing the meaning, getting the point, bridging the gap, and carrying the message: Aspects of discourse following closed head injury in childhood and adolescence. Brain and Language 1990;39:428–446. [PubMed: 2285861] Dennis M, Barnes MA. Oral discourse after early-onset hydrocephalus: Linguistic ambiguity, figurative language, speech acts, and script-based inferences. Journal of Pediatric Psychology 1993;18:639–652. [PubMed: 8295084] Dennis M, Barnes MA. Speech acts after mild or severe childhood head injury. Aphasiology 2000;14:391–405. Dennis M, Barnes MA. Comparison of literal, inferential, and intentional text comprehension in children with mild or severe closed-head injury. Journal of Head Trauma Rehabilitation 2001;16:456–468. [PubMed: 11574041] Dennis M, Barnes MA, Wilkinson M, Humphreys RP. How children with head injury represent real and deceptive emotion in short narratives. Brain and Language 1998;61:450–483. [PubMed: 9570873] Dennis M, Edelstein K, Copeland K, Frederick J, Francis DJ, Hetherington R, et al. Covert orienting to exogenous and endogenous cues in children with spina bifida. Neuropsychologia 2005;43:976– 987. [PubMed: 15716168] Dennis M, Fitz CR, Netley CT, Sugar J, Harwood-Nash DCF, Hendrick EB, et al. The intelligence of hydrocephalic children. Archives of Neurology 1981;38:607–615. [PubMed: 6975094] Dennis M, Hendrick EB, Hoffman HJ, Humphreys RP. The language of hydrocephalic children and adolescents. Journal of Clinical and Experimental Neuropsychology 1987;9:593–621. [PubMed: 3667901] Dennis M, Jacennik B, Barnes MA. The content of narrative discourse in children and adolescents after early-onset hydrocephalus and in normally developing age peers. Brain and Language 1994;46:129–165. [PubMed: 8131040] Dennis M, Kohn B. Comprehension of syntax in infantile hemiplegics after cerebral hemidecortication: Left-hemisphere superiority. Brain and Language 1975;2:472–482. [PubMed: 1218379] J Clin Exp Neuropsychol. Author manuscript; available in PMC 2011 March 15. Dennis Page 18 NIH-PA Author Manuscript NIH-PA Author Manuscript NIH-PA Author Manuscript Dennis M, Lockyer L, Lazenby AL. How high-functioning children with autism understand real and deceptive emotion. Autism 2000;4:371–381. Dennis M, Purvis K, Barnes MA, Wilkinson M, Winner E. Understanding of literal truth, ironic criticism, and deceptive praise following childhood head injury. Brain and Language 2001;78:1– 16. [PubMed: 11412012] Dennis, M.; Spiegler, BJ.; Riva, D.; MacGregor, DL. Neurocognitive outcomes after treatment for childhood brain tumors. In: Walker, D.; Perilongo, G.; Punt, J.; Taylor, R., editors. Brain and spinal tumors of childhood. London: Arnold; 2004. p. 213-227. Dennis M, Whitaker HA. Language acquisition following hemidecortication: Linguistic superiority of the left over the right hemisphere. Brain and Language 1976;3:404–433. [PubMed: 949594] Dews, S.; Winner, E. Attributing meaning to deliberately false utterances: The case of irony. In: Mandell, C.; McCabe, A., editors. The problem of meaning: Behavioral and cognitive perspectives. New York: Elsevier; 1997. p. 377-414. Di Cataldo A, Dollo C, Astuto M, La Spina M, Ippolito S, Papotto M, et al. Mutism after surgical removal of a cerebellar tumor: Two case reports. Pediatric Hematology and Oncology 2001;18:117–121. [PubMed: 11255729] Dogil G, Haider H, Husmann R, Schaner-Wolles C. A radical autonomy of syntax: Evidence from transcortical sensory aphasia. Aphasiology 1995;9:577–602. Doxey D, Bruce D, Sklar F, Swift D, Shapiro K. Posterior fossa syndrome: Identifiable risk factors and irreversible complications. Pediatric Neurosurgery 1999;31:131–136. [PubMed: 10708354] Edelstein K, Dennis M, Copeland K, Francis D, Frederick J, Brandt M, et al. Motor learning in children with spina bifida: Dissociation between performance level and acquisition rate. Journal of the International Neuropsychological Society 2004;10:1–11. [PubMed: 14751002] Eisele JA, Lust B, Aram DM. Presupposition and implication of truth: Linguistic deficits following early brain lesions. Brain and Language 1998;61:376–394. [PubMed: 9570870] Engle RW, Conway ARA, Tuholski SW, Shisler RJ. A resource account of inhibition. Psychological Science 1995;6:122–125. Ewing-Cobbs L, Brookshire B, Scott MA, Fletcher JM. Children’s narratives following traumatic brain injury: Linguistic structure, cohesion, and thematic recall. Brain and Language 1998;61:395–419. [PubMed: 9570871] Feldman HM, Holland AL, Keefe K. Language abilities after left hemisphere brain injury: A case study of twins. Topics in Early Childhood Special Education 1989;9:32–47. Fernandino L, Iacoboni M. Are cortical motor maps based on body parts or coordinated actions? Implications for embodied semantics. Brain and Language. in press. Advance online publication. Retrieved August 28, 2009. 10.1016/j.bandl.2009.02.003 Fischer MH, Zwaan RA. Embodied language: A review of the role of the motor system in language comprehension. Quarterly Journal of Experimental Psychology 2008;61:825–850. Fletcher JM, Barnes M, Dennis M. Language development in children with spina bifida. Seminars in Pediatric Neurology 2002;9:201–208. [PubMed: 12350041] Fletcher JM, Bohan TP, Brandt ME, Kramer LA, Brookshire BL, Thorstad K, et al. Morphometric evaluation of the hydrocephalic brain: Relationships with cognitive development. Child’s Nervous System 1996;12:192–199. Fletcher JM, Copeland K, Frederick JA, Blaser SE, Kramer LA, Northrup H, et al. Spinal lesion level in spina bifida: A source of neural and cognitive heterogeneity. Journal of Neurosurgery (Pediatrics 3) 2005;102:268–279. Fletcher, JM.; Dennis, M.; Northrup, H. Hydrocephalus. In: Yeates, KO.; Ris, MD.; Taylor, HG., editors. Pediatric neuropsychology: Research, theory and practice. New York: Guilford Press; 2000. p. 25-46. Fletcher, P.; Miller, JF. Developmental theory and language disorders. Philadelphia: John Benjamins; 2005. Friedman NP, Miyake A. The relations among inhibition and interference control functions: A latentvariable analysis. Journal of Experimental Psychology: General 2004;133:101–135. [PubMed: 14979754] J Clin Exp Neuropsychol. Author manuscript; available in PMC 2011 March 15. Dennis Page 19 NIH-PA Author Manuscript NIH-PA Author Manuscript NIH-PA Author Manuscript Gallese V, Lakoff G. The brain’s concepts: The role of the sensory motor system in reason and language. Cognitive Neuropsychology 2005;22:455–479. [PubMed: 21038261] Gazzaley A, Cooney JW, McEvoy K, Knight RT, D’Esposito M. Top down enhancement and suppression of the magnitude and speed of neural activity. Journal of Cognitive Neuroscience 2005;17:507–517. [PubMed: 15814009] Gennarelli TA, Graham DI. Neuropathology of the head injuries. Seminars in Clinical Neuropsychiatry 1998;3:160–175. [PubMed: 10085204] Gentilucci M, Gangitano M. Influence of automatic word reading on motor control. European Journal of Neuroscience 1998;10:752–756. [PubMed: 9749737] Gernsbacher, MA. Language comprehension as structure building. Hillsdale, NJ: Lawrence Erlbaum Associates; 1990. Gernsbacher MA. The mechanism of suppression and enhancement in comprehension. Canadian Psychology 1995;36:49–50. Gernsbacher MA, Faust ME. The mechanism of suppression: A component of general comprehension skill. Journal of Experimental Psychology: Learning, Memory, and Cognition 1991;17:245–262. Gernsbacher MA, Robertson RRW. The role of suppression in figurative language comprehension. Journal of Pragmatics 1999;31:1619–1630. Gibbs RW. Semantic analyzability in children’s understanding of idioms. Journal of Speech and Hearing Research 1991;34:613–620. [PubMed: 2072685] Glenberg AM, Kaschak MP. Grounding language in action. Psychonomic Bulletin and Review 2002;9:558–565. [PubMed: 12412897] Glover S, Rosenbaum DA, Graham J, Dixon P. Grasping the meaning of words. Experimental Brain Research 2004;154:103–108. Guttmann E. Aphasia in children. Brain 1942;65:205–219. Hall, WS.; Nagy, WE. Theoretical issues in the investigation of the words of internal report. In: Gopnik, I.; Gopnik, M., editors. From models to modules: Studies in cognitive science from the McGill workshops. Norwood, NJ: Ablex; 1986. p. 26-65. Hannay HJ. Functioning of the corpus callosum in children with early hydrocephalus. Journal of the International Neuropsychological Society 2000;6:351–361. [PubMed: 10824507] Harnishfeger KK, Bjorklund DF. A developmental perspective on individual differences in inhibition. Learning and Individual Differences 1994;6:331–355. Harnishfeger KK, Pope RS. Intending to forget: The development of cognitive inhibition in directed forgetting. Journal of Experimental Child Psychology 1996;62:292–315. [PubMed: 8683190] Harris M, Pexman PM. Children’s perceptions of the social functions of verbal irony. Discourse Processes 2003;36:147–165. Hasan KM, Eluvathingal TJ, Kramer LA, Ewing-Cobbs L, Dennis M, Fletcher JM. White matter microstructural abnormalities in children with spina bifida myelomeningocele and hydrocephalus: A diffusion tractography study of the association pathways. Journal of Magnetic Resonance Imaging 2008;7:700–709. [PubMed: 18302204] Hattiangadi N, Pillion JP, Slomine B, Christensen J, Trovato MK, Speedie LJ. Characteristics of auditory agnosia in a child with severe traumatic brain injury: A case report. Brain and Language 2005;92:12–25. [PubMed: 15582032] Hauk O, Johnsrude F, Pulvermüller F. Somatotopic representation of action words in human motor and premotor cortex. Neuron 2004;41:301–307. [PubMed: 14741110] Haverkate H. A speech act analysis of irony. Journal of Pragmatics 1990;14:77–109. Hécaen H. Acquired aphasia in children: Revisited. Neuropsychologia 1983;21:581–587. [PubMed: 6198596] Hetherington R, Dennis M. Plasticity for recovery, plasticity for development: Cognitive outcome in twins discordant for mid-childhood ischemic stroke. Child Neuropsychology 2004;10:117–128. [PubMed: 15590490] Hoffman HJ, Hendrick EB, Dennis M, Armstrong D. Hemispherectomy for Sturge–Weber syndrome. Child’s Brain 1979;5:233–248. [PubMed: 456102] J Clin Exp Neuropsychol. Author manuscript; available in PMC 2011 March 15. Dennis Page 20 NIH-PA Author Manuscript NIH-PA Author Manuscript NIH-PA Author Manuscript Houghton, G.; Tipper, SP. A model of inhibitory mechanisms in selective attention. In: Dagenbach, D.; Carr, TH., editors. Inhibitory processes in attention, memory, and language. San Diego, CA: Academic Press; 1994. p. 53-112. Huber JF, Dennis M, Bradley K, Spiegler BJ. Long-term neuromotor speech deficits in survivors of childhood posterior fossa tumors: Effects of tumor type, radiation, age at diagnosis, and survival years. Journal of Child Neurology 2007;22:848–854. [PubMed: 17715277] Huber-Okrainec J, Blaser SE, Dennis M. Idiom comprehension deficits in relation to corpus callosum agenesis and hypoplasia in children with spina bifida myelomeningocele. Brain and Language 2005;93:349–368. [PubMed: 15862859] Huber-Okrainec J, Dennis M, Bradley K, Spiegler BJ. Long-term effects of transient cerebellar mutism after cerebellar astrocytoma or medulloblastoma tumor resection in childhood. Child’s Nervous System 2006;22:132–138. Huber-Okrainec J, Dennis M, Brettschneider J, Spiegler B. Neuromotor speech deficits in children and adults with spina bifida and hydrocephalus. Brain and Language 2002;80:592–602. [PubMed: 11896659] Hudson, LJ. Speech and language disorders in childhood brain tumours. In: Murdoch, BE., editor. Acquired neurological speech/language disorders in childhood. London: Taylor & Francis; 1990. p. 245-268. Hudson, LJ.; Buttsworth, DL.; Murdoch, BE. Effect of CNS prophylaxis on speech and language function in children. In: Murdoch, BE., editor. Acquired neurological speech/language disorders in childhood. London: Taylor & Francis; 1990. p. 269-307. Hudson LJ, Murdoch BE, Ozanne AE. Posterior fossa tumours in childhood: Associated speech and language disorders post-surgery. Aphasiology 1989;3:1–18. Humphreys RP. Mutism after posterior fossa surgery. Concepts in Pediatric Neurosurgery 1989;9:57– 64. Hynd GW, Leathem J, Semrud-Clikeman M, Hern KL, Wenner M. Anomic aphasia in childhood. Journal of Child Neurology 1995;10:189–293. Hynd GW, Semrud-Clikeman M, Lorys AR, Novey ES, Eliopulos D. Brain morphology in developmental dyslexia and attention deficit disorder/hyperactivity. Archives of Neurology 1990;47:919–926. [PubMed: 2375699] Jarema, G. Impaired morphological processing. In: Stemmer, B.; Whitaker, HA., editors. Handbook of the neuroscience of language. New York: Elsevier; 2008. p. 137-146. Jordan, FM. Speech and language disorders following childhood closed head injury. In: Murdoch, BE., editor. Acquired neurological speech/language disorders in childhood. London: Taylor & Francis; 1990. p. 124-147. Jordan FM, Murdoch BE. A prospective study of the linguistic skills of children with closed-head injuries. Aphasiology 1993;7:503–512. Jordan FM, Ozanne AE, Murdoch BE. Long-term speech and language disorders subsequent to closed head injury in children. Brain Injury 1988;2:179–185. [PubMed: 2458791] Jordan FM, Ozanne AE, Murdoch BE. Performance of closed head-injured children on a naming task. Brain Injury 1990;4:27–32. [PubMed: 2297597] Karttunen L. Implicative verbs. Language 1971;47:340–358. Kemmerer D, Gonzalez Castillo J, Talavage T, Patterson S, Wiley C. Neuroanatomical distribution of five semantic components of verbs: Evidence. Brain and Language 2008;107:16–43. [PubMed: 17977592] Kempson, RM. Presupposition and the delimitation of semantics. Cambridge, UK: Cambridge University Press; 1975. Kintsch W. The role of knowledge in discourse comprehension: A construction-integration model. Psychological Review 1988;95:163–182. [PubMed: 3375398] Kiparsky, P.; Kiparsky, C. Fact. In: Bierwisch, M.; Heidolph, KE., editors. Progress in linguistics: A collection of papers. The Hague: Mouton; 1970. p. 143-173. Kipp K. A developmental perspective on the measurement of cognitive deficits in attention-deficit/ hyperactivity disorder. Biological Psychiatry 2005;57:1256–1260. [PubMed: 15949996] J Clin Exp Neuropsychol. Author manuscript; available in PMC 2011 March 15. Dennis Page 21 NIH-PA Author Manuscript NIH-PA Author Manuscript NIH-PA Author Manuscript Klein SK, Masur D, Farber K, Shinnar S, Rapin I. Fluent aphasia in children: Definition and natural history. Child Neurology 1992;7:50–59. Kohn B. Right-hemisphere speech representation and comprehension of syntax after left cerebral injury. Brain and Language 1980;9:350–361. [PubMed: 6767522] Landau WM, Kleffner FR. Syndrome of acquired aphasia with convulsive disorder in children. Neurology 1957;7:523–530. [PubMed: 13451887] Lazar RT, Warr-Leeper GA, Nicholson CB, Johnson S. Elementary school teachers’ use of multiple meaning expressions. Language, Speech, and Hearing Services in Schools 1989;20:420–430. Levelt, WJM. Speaking: From intention to articulation. Cambridge, MA: MIT Press; 1989. Libben, G. Disorders of lexis. In: Stemmer, B.; Whitaker, HA., editors. Handbook of the neuroscience of language. New York: Elsevier; 2008. p. 147-154. Lidzba K, Wilke M, Staudt M, Krägeloh-Mann I, Grodd W. Reorganization of the cerebro-cerebellar network of language production in patients with congenital left-hemispheric brain lesions. Brain and Language 2008;106:204–210. [PubMed: 18158178] Liégeois F, Connelly A, Baldeweg T, Vargha-Khadem F. Speaking with a single cerebral hemisphere: fMRI language organization after hemispherectomy in childhood. Brain and Language 2008;106:195–203. [PubMed: 18329093] Linebarger, MC. Neuropsychology of sentence parsing. In: Caramazza, A., editor. Cognitive neuropsychology and neurolinguistics: Advances in models of cognitive function and impairment. Hove, UK: Psychology Press; 1990. p. 55-122. Loonen MCB, Van Dongen HR. Acquired childhood aphasia: Outcome one year after onset. Archives of Neurology 1990;47:1324–1328. [PubMed: 1701299] Love T, Swinney D, Walenski M, Zurif E. How left inferior frontal cortex participates in syntactic processing: Evidence from aphasia. Brain and Language 2008;107:203–219. [PubMed: 18158179] Lovett MW, Dennis M, Newman JE. Making reference: The cohesive use of pronouns in the narrative discourse of hemidecorticate adolescents. Brain and Language 1986;29:224–251. [PubMed: 2431738] Lyon GR. Toward a definition of dyslexia. Annals of Dyslexia 1995;45:3–27. MacWhinney B, Leinbach J. Implementations are not conceptualizations: Revising the verb learning model. Cognition 1991;40:121–157. [PubMed: 1786671] Mahon BZ, Caramazza A. Concepts and categories: A cognitive neuropsychological perspective. Annual Reviews of Psychology 2009;60:27–51. Majerus S, Van der Linden M, Poncelet M, Metz-Lutz MN. Can phonological and semantic short-term memory be associated? Further evidence from Landau–Kleffner syndrome. Cognitive Neuropsychology 2004;21:491–512. [PubMed: 21038217] Makino A, Soga T, Obayashi M, Seo Y, Ebisutani D, Horie S, et al. Cortical blindness caused by acute general cerebral swelling. Surgical Neurology 1988;29:393–400. [PubMed: 3363476] Malle, BF.; Moses, LJ.; Baldwin, D. Introduction: The significance of intentionality. In: Malle, BF.; Moses, LJ.; Baldwin, DA., editors. Intentions and intentionality: Foundations of social cognition. Cambridge, MA: MIT Press; 2001. p. 1-24. Martin A, Caramazza A. Neuropsychological and neuroimaging perspectives on conceptual knowledge: An introduction. Cognitive Neuropsychology 2003;20:195–212. [PubMed: 20957570] McMillan HJ, Keene DL, Matzinger MA, Vassilyadi M, Nzau M, Ventureyra ECG. Brainstem compression: A predictor of postoperative cerebellar mutism. Child’s Nervous System 2009;25:677–681. Menn, L.; Obler, L.; Goodglass, H. A cross-language study of agrammatism. Philadelphia: Benjamins; 1990. Moleski M. Neuropsychological, neuroanatomical, and neurophysiological consequences of CNS chemotherapy for acute lymphoblastic leukemia. Archives of Clinical Neuropsychology 2000;15:603–630. [PubMed: 14590198] J Clin Exp Neuropsychol. Author manuscript; available in PMC 2011 March 15. Dennis Page 22 NIH-PA Author Manuscript NIH-PA Author Manuscript NIH-PA Author Manuscript Morrow, DG.; Bower, GH.; Greenspan, SL. Situation-based inferences during narrative comprehension. In: Graesser, AC.; Bower, GH., editors. Inferences and text comprehension. San Diego, CA: Academic Press; 1990. p. 123-135. Murdoch, BE.; Ozanne, AE. Linguistic status following acute cerebral anoxia in children. In: Murdoch, BE., editor. Acquired neurological speech/language disorders in childhood. London: Taylor & Francis; 1990. p. 177-198. Ni W, Constable RT, Mencl WE, Pugh KR, Fulbright RK, Shaywitz SE, et al. An event-related neuroimaging study distinguishing form and content in sentence processing. Journal of Cognitive Neuroscience 2000;12:120–133. [PubMed: 10769310] Noveck IA, Reboul A. Experimental pragmatics: A Gricean turn in the study of language. Trends in Cognitive Sciences 2008;12:425–431. [PubMed: 18805727] Ozanne, AE.; Murdoch, BE. Acquired childhood aphasia: Neuropathology, linguistic characteristics and prognosis. In: Murdoch, BE., editor. Acquired neurological speech/language disorders in childhood. London: Taylor & Francis; 1990. p. 1-65. Ozanne, AE.; Murdoch, BE.; Krimmer, HL. Linguistic problems associated with childhood metabolic disorders. In: Murdoch, BE., editor. Acquired neurological speech/language disorders in childhood. London: Taylor & Francis; 1990. p. 199-215. Paquier P, Saerens J, Parizel PM, Van Dongen H, De La Porte C, De Moor J. Acquired reading disorder similar to pure alexia in a child with ruptured arteriovenous malformation. Aphasiology 1989;3:667–676. Paquier P, Van Dongen HR. Two contrasting cases of fluent aphasia in children. Aphasiology 1991;5:235–245. Paquier P, Van Dongen HR. Current trends in acquired childhood aphasia: An introduction. Aphasiology 1993;7:421–440. Pascual-Leone J. If the magical number is 4, how does one account for operations within working memory? Brain and Behavioral Sciences 2001;24:136–138. Paul LK, Van Lancker-Sidtis D, Schieffer B, Dietrich R, Brown WS. Communicative deficits in agenesis of the corpus callosum: Nonliteral language and affective prosody. Brain and Language 2003;85:313–324. [PubMed: 12735947] Perfetti, CA.; Frishkoff, GA. The neural bases of text and discourse processing. In: Stemmer, B.; Whitaker, HA., editors. Handbook of the neuroscience of language. New York: Elsevier; 2008. p. 165-174. Perner J, Lang B, Kloo D. Theory of mind and self-control: More than a common problem of inhibition. Child Development 2002;73:752–767. [PubMed: 12038549] Pitchford NJ. Spoken language correlates of reading impairments acquired in childhood. Brain and Language 2000;72:129–149. [PubMed: 10722784] Plante E, Holland SK, Schmithorst VJ. Prosodic processing by children: An fMRI study. Brain and Language 2006;97:332–342. [PubMed: 16460792] Pollio, HR.; Barlow, JM.; Fine, HJ.; Pollio, MR. Psychology and the poetics of growth: Figurative language in psychology, psychotherapy, and education. Hillsdale, NJ: Lawrence Erlbaum Associates, Inc; 1977. Pugh KR, Menci WE, Jenner AR, Katz L, Frost SJ, Lee JR, et al. Functional neuroimaging studies of reading and reading disability (developmental dyslexia). Mental Retardation and Developmental Disabilities Research Reviews 2000;6:207–213. [PubMed: 10982498] Rapin I. Acquired aphasia in children. Journal of Child Neurology 1995;10:267–270. [PubMed: 7594260] Reilly JS, Bates EA, Marchman VA. Narrative discourse in children with early focal brain injury. Brain and Language 1998;61:335–375. [PubMed: 9570869] Rekate HL, Grubb RL, Aram DM, Hahn JF, Ratcheson RA. Muteness of cerebellar origin. Archives of Neurology 1985;42:697–698. [PubMed: 4015467] Richards, JE. The development of visual attention and the brain. In: de Haan, M.; Johnson, MH., editors. The cognitive neuroscience of development. Hove, UK: Psychology Press; 2003. p. 73-98. J Clin Exp Neuropsychol. Author manuscript; available in PMC 2011 March 15. Dennis Page 23 NIH-PA Author Manuscript NIH-PA Author Manuscript NIH-PA Author Manuscript Ris, MD.; Grueneich, R. Sickle cell disease. In: Yeates, KO.; Ris, MD.; Taylor, HG., editors. Pediatric neuropsychology: Research, theory and practice. New York: Guilford Press; 2000. p. 320-335. Saarni, C. The development of emotional competence. London: Guilford Press; 1999. Sanford AJ, Sturt P. Depth of processing in language comprehension: Not noticing the evidence. Trends in Cognitive Science 2002;6:382–386. Sartori G, Job R. The oyster with four legs: A neuropsychological study on the interaction of visual and semantic information. Cognitive Neuropsychology 1988;5:105–132. Schmalhofer F, McDaniel MA, Keefe D. A unified model for predictive and bridging inferences. Discourse Processes 2002;33:105–132. Schwartz, RG., editor. Handbook of language disorders. New York: Psychology Press; 2008. Searle, JR. Speech acts: An essay in the philosophy of language. Cambridge, UK: Cambridge University Press; 1969. Shriberg LD, Aram DM, Kwiatkowski J. Developmental apraxia of speech: I. Descriptive and theoretical perspectives. Journal of Speech, Language, and Hearing Research 1997a;40:273–285. Shriberg LD, Aram DM, Kwiatkowski J. Developmental apraxia of speech: II. Toward a diagnostic marker. Journal of Speech, Language, and Hearing Research 1997b;40:286–312. Simos PG, Breier JI, Fletcher JM, Bergman E, Papanicolaou AC. Cerebral mechanisms involved in word reading in dyslexic children: A magnetic source imaging approach. Cerebral Cortex 2000;10:809–816. [PubMed: 10920052] Smyth, V.; Ozanne, AE.; Woodhouse, LM. Communicative disorders in childhood infectious diseases. In: Murdoch, BE., editor. Acquired neurological speech/language disorders in childhood. London: Taylor & Francis; 1990. p. 148-176. Stark RE, Bleile K, Brandt J, Freeman J, Vining EPG. Speech-language outcomes of hemispherectomy in children and young adults. Brain and Language 1995;51:406–421. [PubMed: 8719074] Stemmer, B. Neuropragmatics: Disorders and neural systems. In: Stemmer, B.; Whitaker, HA., editors. Handbook of the neuroscience of language. New York: Elsevier; 2008. p. 175-187. Stromswold K, Caplan D, Alpert N, Rauch S. Localization of syntactic comprehension by positron emission tomography. Brain and Language 1996;52:452–473. [PubMed: 8653390] Stronach ST, Turkstra LS. Theory of mind and use of cognitive state terms by adolescents with traumatic brain injury. Aphasiology 2008;22:1054–1070. Swinney D, Zurif E, Prather P, Love T. Neurological distribution of processing resources underlying language comprehension. Journal of Cognitive Neuroscience 1996;8:174–184. Taylor, EM. Psychological appraisal of children with cerebral defects. Cambridge, MA: Harvard University Press; 1961. Tettamanti M, Buccino G, Saccuman MC, Gallese V, Danna M, Scifo P, et al. Listening to actionrelated sentences activates fronto-parietal motor circuits. Journal of Cognitive Neuroscience 2005;17:273–281. [PubMed: 15811239] Tompkins CA, Lehman-Blake MT, Baumgaertner A, Fassbinder W. Characterising comprehension difficulties after right brain damage: Attentional demands of suppression function. Aphasiology 2002;16:559–572. Ullman, MT. The role of memory systems in disorders of language. In: Stemmer, B.; Whitaker, HA., editors. Handbook of the neuroscience of language. New York: Elsevier; 2008. p. 189-198. Ullman MT, Corkin S, Coppola M, Hickok G, Growdon JH, Koroshetz WJ, et al. A neural dissociation within language: Evidence that the mental dictionary is part of declarative memory, and that grammatical rules are processed by the procedural system. Journal of Cognitive Neuroscience 1997;9:266–276. Valstar MJ, Ruijter GJG, van Diggelen OP, Poorthuis BJ, Wijburg FA. Sanfilippo syndrome: A minireview. Journal of Inherited Metabolic Disorders 2008;31:240–252. Van den Broek, P.; Young, M.; Tzeng, Y.; Linderholm, T. The landscape model of reading: Inferences and the online construction of a memory representation. In: van Oostendorp, H.; Goldman, SR., editors. The construction of mental representation during reading. Mahwah, NJ: Lawrence Erlbaum Associates, Inc; 1999. p. 71-98. Van Dijk, TA.; Kintsch, W. Strategies of discourse comprehension. New York: Academic Press; 1983. J Clin Exp Neuropsychol. Author manuscript; available in PMC 2011 March 15. Dennis Page 24 NIH-PA Author Manuscript NIH-PA Author Manuscript NIH-PA Author Manuscript Van Dongen HR, Catsman-Berrevoets CE, van Mourik M. The syndrome of “cerebellar” mutism and subsequent dysarthria. Neurology 1994;44:2040–2046. [PubMed: 7969956] Van Dongen HR, Loonen MCB. Factors related to prognosis of acquired aphasia in children. Cortex 1977;13:131–136. [PubMed: 16295957] Van Dongen HR, Loonen MCB, Van Dongen KJ. Anatomical basis for acquired fluent aphasia in children. Annals of Neurology 1985;17:306–309. [PubMed: 3994318] Van Dongen, HR.; Paquier, P. Fluent aphasia in children. In: Martins, IP.; Castro-Caldas, A.; Van Dongen, HR.; Van Hout, A., editors. Acquired aphasia in children. Dordrecht, The Netherlands: Kluwer Academic; 1991. p. 125-141. Van Hout, A. Characteristics of language in acquired aphasia in children. In: Martins, IP.; CastroCaldas, A.; Van Dongen, HR.; Van Hout, A., editors. Acquired aphasia in children. Dordrecht, The Netherlands: Kluwer Academic; 1991. p. 117-124. Van Hout A, Evrard P, Lyon G. On the positive semiology of acquired aphasia in children. Developmental Medicine and Child Neurology 1985;27:231–241. [PubMed: 2581836] Van Lancker-Sidtis, D. The relation of human language to human emotion. In: Stemmer, B.; Whitaker, HA., editors. Handbook of the neuroscience of language. New York: Elsevier; 2008. p. 199-207. Van Mourik M, Catsman-Berrevoets CE, Yousef-Bak E, Paquier PF, Van Dongen HR. Dysarthria in children with cerebellar or brainstem tumors. Pediatric Neurology 1998;18:411–414. [PubMed: 9650681] Visch-Brink EG, Van de Sandt-Koenderman M. The occurrence of paraphasias in the spontaneous speech of children with an acquired aphasia. Brain and Language 1984;23:258–271. [PubMed: 6083818] Wellman HM, Cross D, Watson J. Meta-analysis of theory-of-mind development: The truth about false belief. Child Development 2001;72:655–684. [PubMed: 11405571] Whitney P. Psychological theories of elaborative inferences: Implications for schema-theoretic views of comprehension. Reading Research Quarterly 1987;22:299–310. Williams BR, Ponesse JS, Schachar RJ, Logan GD, Tannock R. Development of inhibitory control across the life span. Developmental Psychology 1999;35:205–213. [PubMed: 9923475] Williams LJ, Rasmussen SA, Flores A, Kirby RS, Edmonds LD. Decline in the prevalence of spina bifida and anencephaly by race/ethnicity: 1995–2002. Pediatrics 2005;116:580–586. [PubMed: 16140696] Williams, J.; Sharp, GB. Epilepsy. In: Yeates, KO.; Ris, MD.; Taylor, HG., editors. Pediatric neuropsychology: Research, theory, and practice. New York: Guilford Press; 2000. p. 47-73. Withers HR. Biological basis of radiation therapy for cancer. Lancet 1992;339:156–159. [PubMed: 1346018] Woods BT, Teuber HL. Changing patterns of childhood aphasia. Annals of Neurology 1978;3:273– 280. [PubMed: 666267] Yeates KO, Dennis M, Rubin KH, Taylor HG, Bigler ED, Gerhardt CA, et al. Social outcomes in childhood brain disorder: A heuristic integration of social neuroscience and developmental psychology. Psychological Bulletin 2007;133:535–556. [PubMed: 17469991] Zwaan, RA. The immersed experiencer: Toward an embodied theory of language comprehension. In: Ross, BH., editor. The psychology of learning and motivation. New York: Academic; 2004. p. 35-62. Zwaan RA, Langston MC, Graesser AC. The construction of situation models in narrative comprehension: An event-indexing model. Psychological Science 1995;6:292–297. Zwaan RA, Radvansky GA. Situation models in language comprehension and memory. Psychological Bulletin 1998;123:162–185. [PubMed: 9522683] Zwaan RA, Taylor LJ. Seeing, acting, understanding: Motor resonance in language comprehension. Journal of Experimental Psychology 2006;135:1–11. [PubMed: 16478313] Zwaan RA, Taylor LJ, de Boer M. Motor resonance as a function of narrative time: Further tests of the linguistic focus hypothesis. Brain and Language. in press. J Clin Exp Neuropsychol. Author manuscript; available in PMC 2011 March 15. Dennis Page 25 NIH-PA Author Manuscript Figure 1. Language taxonomy. The leftmost column shows levels of language representation. The next column shows functional domains within each representation level. The next column shows examples of each functional domain. The rightmost column provides examples of clinical deficits for each functional domain. NIH-PA Author Manuscript NIH-PA Author Manuscript J Clin Exp Neuropsychol. Author manuscript; available in PMC 2011 March 15.