Papers by Francesca Carota
The Journal of Neuroscience
Language production involves a complex set of computations, from conceptualization to articulatio... more Language production involves a complex set of computations, from conceptualization to articulation, which are thought to engage cascading neural events in the language network. However, recent neuromagnetic evidence suggests simultaneous meaning-to-speech mapping in picture naming tasks, as indexed by early parallel activation of frontotemporal regions to lexical semantic, phonological, and articulatory information. Here we investigate the time course of word production, asking to what extent such "earliness" is a distinctive property of the associated spatiotemporal dynamics. Using MEG, we recorded the neural signals of 34 human subjects (26 males) overtly naming 134 images from four semantic object categories (animals, foods, tools, clothes). Within each category, we covaried word length, as quantified by the number of syllables contained in a word, and phonological neighborhood density to target lexical and post-lexical phonological/phonetic processes. Multivariate pattern analyses searchlights in sensor space distinguished the stimulus-locked spatiotemporal responses to object categories early on, from 150 to 250 ms after picture onset, whereas word length was decoded in left frontotemporal sensors at 250-350 ms, followed by the latency of phonological neighborhood density (350-450 ms). Our results suggest a progression of neural activity from posterior to anterior language regions for the semantic and phonological/phonetic computations preparing overt speech, thus supporting serial cascading models of word production.
Sensorimotor areas activate to action- and object-related words, but their role in abstract meani... more Sensorimotor areas activate to action- and object-related words, but their role in abstract meaning processing is still debated. Abstract emotion words denoting body internal states are a critical test case because they lack referential links to objects. If actions expressing emotion are crucial for learning correspondences between word forms and emotions, emotion word--evoked activity should emerge in motor brain systems controlling the face and arms, which typically express emotions. To test this hypothesis, we recruited 18 native speakers and used event-related functional magnetic resonance imaging to compare brain activation evoked by abstract emotion words to that by face- and arm-related action words. In addition to limbic regions, emotion words indeed sparked precentral cortex, including body-part--specific areas activated somatotopically by face words or arm words. Control items, including hash mark strings and animal words, failed to activate precentral areas. We conclude t...
The present paper investigates the major derivational strategies underlying the formation of suff... more The present paper investigates the major derivational strategies underlying the formation of suffixed words in Italian, with the purpose of tackling the issue of their formalization. After having specified the theoretical cognitive premises that orient the work, the interacting component modules of the suffixation process, i.e. morphonology, morphotactics and affixal semantics, are explored empirically, by drawing ample naturally occurring data on a Corpus of written Italian. A special attention is paid to the semantic mechanisms that are involved into suffixation. Some semantic nuclei are identified for the major suffixed word types of Italian, which are due to word formation rules active at the synchronic level, and a semantic configuration of productive suffixes is suggested. A general framework is then sketched, which combines classical finite-state methods with a feature unification-based word grammar. More specifically, the semantic information specified for the affixal materi...
Cerebral cortex (New York, N.Y. : 1991), Jan 10, 2017
Language comprehension engages a distributed network of frontotemporal, parietal, and sensorimoto... more Language comprehension engages a distributed network of frontotemporal, parietal, and sensorimotor regions, but it is still unclear how meaning of words and their semantic relationships are represented and processed within these regions and to which degrees lexico-semantic representations differ between regions and semantic types. We used fMRI and representational similarity analysis to relate word-elicited multivoxel patterns to semantic similarity between action and object words. In left inferior frontal (BA 44-45-47), left posterior middle temporal and left precentral cortex, the similarity of brain response patterns reflected semantic similarity among action-related verbs, as well as across lexical classes-between action verbs and tool-related nouns and, to a degree, between action verbs and food nouns, but not between action verbs and animal nouns. Instead, posterior inferior temporal cortex exhibited a reverse response pattern, which reflected the semantic similarity among obj...
Journal of Cognitive Neuroscience, 2016
Derivational morphology is a cross-linguistically dominant mechanism for word formation, combinin... more Derivational morphology is a cross-linguistically dominant mechanism for word formation, combining existing words with derivational affixes to create new word forms. However, the neurocognitive mechanisms underlying the representation and processing of such forms remain unclear. Recent cross-linguistic neuroimaging research suggests that derived words are stored and accessed as whole forms, without engaging the left-hemisphere perisylvian network associated with combinatorial processing of syntactically and inflectionally complex forms. Using fMRI with a “simple listening” no-task procedure, we reexamine these suggestions in the context of the root-based combinatorially rich Italian lexicon to clarify the role of semantic transparency (between the derived form and its stem) and affix productivity in determining whether derived forms are decompositionally represented and which neural systems are involved. Combined univariate and multivariate analyses reveal a key role for semantic tr...
Selected Papers from the IADA Chicago 2004 Conference
Deixis, or pointing, is crucial in communication (Kita, 2003). Previous works suggest that manual... more Deixis, or pointing, is crucial in communication (Kita, 2003). Previous works suggest that manual pointing would recruit the left posterior parietal and frontal cortex (Astafiev et al., 2003). Prosodic and syntactic pointing would share a common neural network (Lœvenbruck et al., 2005). To test the hypothesis that multimodal deixis involves a common network, we designed an fMRI paradigm integrating four conditions: 1) prosodic focus, 2) syntactic extraction, 3) index finger pointing, 4) eye pointing.
Conscious Will and Responsibility, 2010
This chapter focuses on the issue of motor awareness. It addresses three main questions: What exa... more This chapter focuses on the issue of motor awareness. It addresses three main questions: What exactly are we aware of when making a movement? What is the contribution of afferent and efferent signals to motor awareness? What are the neural bases of motor awareness? It reviews evidence that the motor system is mainly aware of its intention. As long as the goal is achieved, nothing reaches awareness about the kinematic details of the ongoing movements, even when substantial corrections have to be implemented to attain the intended state. The chapter also shows that motor awareness relies mainly on the central predictive computations carried out within the posterior parietal cortex. The outcome of these computations is contrasted with the peripheral reafferent input to build a veridical motor awareness. Some evidence exists that this process involves the premotor areas.
Cerebral Cortex, 2011
denoting body internal states are a critical test case because they lack referential links to obj... more denoting body internal states are a critical test case because they lack referential links to objects. If actions expressing emotion are crucial for learning correspondences between word forms and emotions, emotion word-evoked activity should emerge in motor brain systems controlling the face and arms, which typically express emotions. To test this hypothesis, we recruited 18 native speakers and used event-related functional magnetic resonance imaging to compare brain activation evoked by abstract emotion words to that by face-and arm-related action words. In addition to limbic regions, emotion words indeed sparked precentral cortex, including body-part-specific areas activated somatotopically by face words or arm words. Control items, including hash mark strings and animal words, failed to activate precentral areas. We conclude that, similar to their role in action word processing, activation of frontocentral motor systems in the dorsal stream reflects the semantic binding of sign and meaning of abstract words denoting emotions and possibly other body internal states.
Neuronal populations code similar concepts by similar activity patterns across the human brain’s ... more Neuronal populations code similar concepts by similar activity patterns across the human brain’s networks supporting language comprehension. However, it is unclear to what extent such meaning-to-symbol mapping reflects statistical distributions of symbol meanings in language use, as quantified by word co-occurrence frequencies, or, rather, experiential information thought to be necessary for grounding symbols in sensorimotor knowledge. Here we asked whether integrating distributional semantics with human judgments of grounded sensorimotor semantics better approximates the representational similarity of conceptual categories in the brain, as compared with each of these methods used separately. We examined the similarity structure of activation patterns elicited by action- and object-related concepts using multivariate representational similarity analysis (RSA) of fMRI data. The results suggested that a semantic vector integrating both sensorimotor and distributional information yield...
Pragmatics Beyond New Series, 2007
When understanding language semantically related to actions, the motor cortex is active and may b... more When understanding language semantically related to actions, the motor cortex is active and may be sensitive to semantic information, for example about the body-part-relationship of displayed action-related words. Conversely, movements of the hands or feet can impair memory performance for arm- and leg-related action words respectively, suggesting that the role of motor systems extends to verbal working memory. Here, we studied brain correlates of verbal memory load for action-related words using event-related fMRI during the encoding and memory maintenance of word lists. Seventeen participants saw either four identical or four different words from the same category, semantically related to actions typically performed either with the arms or with the legs. After a variable delay of 4-14 seconds, they performed a nonmatching-to-sample task. Hemodynamic activity related to the information load of words at presentation was most prominent in left temporo-occipital and bilateral posterio...
A class of semantic theories defines concepts in terms of statistical distributions of lexical it... more A class of semantic theories defines concepts in terms of statistical distributions of lexical items, basing meaning on vectors of word co-occurrence frequencies. A different approach emphasizes abstract hierarchical taxonomic relationships among concepts. However, the functional relevance of these different accounts and how they capture information-encoding of lexical meaning in the brain still remains elusive. We investigated to what extent distributional and taxonomic models explained word-elicited neural responses using cross-validated representational similarity analysis (RSA) of functional magnetic resonance imaging (fMRI) and model comparisons. Our findings show that the brain encodes both types of semantic information, but in distinct cortical regions. Posterior middle temporal regions reflected lexical-semantic similarity based on hierarchical taxonomies, in coherence with the action-relatedness of specific semantic word categories. In contrast, distributional semantics best predicted the representational patterns in left inferior frontal gyrus (LIFG, BA 47). Both representations coexisted in the angular gyrus supporting semantic binding and integration. These results reveal that neuronal networks with distinct cortical distributions across higher-order association cortex encode different representa-tional properties of word meanings. Taxonomy may shape long-term lexical-semantic representations in memory consistently with the sensorimotor details of semantic categories, whilst distributional knowledge in the LIFG (BA 47) may enable semantic combinatorics in the context of language use. Our approach helps to elucidate the nature of semantic representations essential for understanding human language .
Cerebral Cortex, 2012
Sensorimotor areas activate to action-and object-related words, but their role in abstract meanin... more Sensorimotor areas activate to action-and object-related words, but their role in abstract meaning processing is still debated. Abstract emotion words denoting body internal states are a critical test case because they lack referential links to objects. If actions expressing emotion are crucial for learning correspondences between word forms and emotions, emotion word--evoked activity should emerge in motor brain systems controlling the face and arms, which typically express emotions. To test this hypothesis, we recruited 18 native speakers and used event-related functional magnetic resonance imaging to compare brain activation evoked by abstract emotion words to that by face-and arm-related action words. In addition to limbic regions, emotion words indeed sparked precentral cortex, including body-part--specific areas activated somatotopically by face words or arm words. Control items, including hash mark strings and animal words, failed to activate precentral areas. We conclude that, similar to their role in action word processing, activation of frontocentral motor systems in the dorsal stream reflects the semantic binding of sign and meaning of abstract words denoting emotions and possibly other body internal states.
Language comprehension engages a distributed network of frontotemporal, parietal, and sensorimoto... more Language comprehension engages a distributed network of frontotemporal, parietal, and sensorimotor regions, but it is still unclear how meaning of words and their semantic relationships are represented and processed within these regions and to which degrees lexico-semantic representations differ between regions and semantic types. We used fMRI and representational similarity analysis to relate word-elicited multivoxel patterns to semantic similarity between action and object words. In left inferior frontal (BA 44-45-47), left posterior middle temporal and left precentral cortex, the similarity of brain response patterns reflected semantic similarity among action-related verbs, as well as across lexical classes-between action verbs and tool-related nouns and, to a degree, between action verbs and food nouns, but not between action verbs and animal nouns. Instead, posterior inferior temporal cortex exhibited a reverse response pattern, which reflected the semantic similarity among object-related nouns, but not action-related words. These results show that semantic similarity is encoded by a range of cortical areas, including multimodal association (e.g., anterior inferior frontal, posterior middle temporal) and modality-preferential (premotor) cortex and that the representational geometries in these regions are partly dependent on semantic type, with semantic similarity among action-related words crossing lexical-semantic category boundaries.
■ Derivational morphology is a cross-linguistically dominant mechanism for word formation, combin... more ■ Derivational morphology is a cross-linguistically dominant mechanism for word formation, combining existing words with derivational affixes to create new word forms. However, the neurocognitive mechanisms underlying the representation and processing of such forms remain unclear. Recent cross-linguistic neuroimaging research suggests that derived words are stored and accessed as whole forms, without engaging the left-hemisphere perisylvian network associated with combi-natorial processing of syntactically and inflectionally complex forms. Using fMRI with a " simple listening " no-task procedure, we reexamine these suggestions in the context of the root-based combinatorially rich Italian lexicon to clarify the role of semantic transparency (between the derived form and its stem) and affix productivity in determining whether derived forms are decompositionally represented and which neural systems are involved. Combined univariate and multivariate analyses reveal a key role for semantic transparency, modulated by affix productivity. Opaque forms show strong cohort competition effects, especially for words with nonproductive suffixes (ventura, " destiny "). The bilateral frontotemporal activity associated with these effects indicates that opaque derived words are processed as whole forms in the bihemispheric language system. Semantically transparent words with productive affixes (libreria, " bookshop ") showed no effects of lexical competition, suggesting morphologically structured co-representation of these derived forms and their stems, whereas transparent forms with non-productive affixes (pineta, pine forest) show intermediate effects. Further multivariate analyses of the transparent derived forms revealed affix productivity effects selectively involving left inferior frontal regions, suggesting that the combinatorial and decompo-sitional processes triggered by such forms can vary significantly across languages. ■
■ Derivational morphology is a cross-linguistically dominant mechanism for word formation, combin... more ■ Derivational morphology is a cross-linguistically dominant mechanism for word formation, combining existing words with derivational affixes to create new word forms. However, the neurocognitive mechanisms underlying the representation and processing of such forms remain unclear. Recent crosslinguistic neuroimaging research suggests that derived words are stored and accessed as whole forms, without engaging the left-hemisphere perisylvian network associated with combinatorial processing of syntactically and inflectionally complex forms. Using fMRI with a "simple listening" no-task procedure, we reexamine these suggestions in the context of the rootbased combinatorially rich Italian lexicon to clarify the role of semantic transparency (between the derived form and its stem) and affix productivity in determining whether derived forms are decompositionally represented and which neural systems are involved. Combined univariate and multivariate analyses reveal a key role for semantic transparency, modulated by affix productivity. Opaque forms show strong cohort competition effects, especially for words with nonproductive suffixes (ventura, "destiny"). The bilateral frontotemporal activity associated with these effects indicates that opaque derived words are processed as whole forms in the bihemispheric language system. Semantically transparent words with productive affixes (libreria, "bookshop") showed no effects of lexical competition, suggesting morphologically structured co-representation of these derived forms and their stems, whereas transparent forms with nonproductive affixes ( pineta, pine forest) show intermediate effects.
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Papers by Francesca Carota