Mental processes

Cognition is thought to result from interactions within large-scale networks of brain regions. Here we propose a method to identify these large-scale networks using functional magnetic resonance imaging (fMRI). Regions belonging to such networks are defined as sets of strongly interacting regions, each of which showing an homogeneous temporal activity. Our method of large-scale network identification (LSNI) proceeds by first detecting functionally homogeneous regions. The networks of functional interconnections are then found by comparing the correlations among these regions against a model of the correlations in the noise.

Recent research has demonstrated that cortical motor areas are engaged when observing motor actions of others. However, little is known about the possible contribution of the motor system for evaluating the correctness of others' actions. To address this question we designed an MEG experiment in which subjects were executing and observing motor actions with and without errors. In the execution task subjects were asked to make speeded button presses according to instruction cues. During the observation task, they viewed pictures of an actor's hand making button presses which were correct or incorrect according to the cues. Time-frequency representations of the MEG data demonstrated a depression in oscillatory activity in the beta band activity (15-35 Hz) during execution followed by a beta rebound that was stronger for incorrect compared to correct executions. During the observation task, a similar time-course of the beta activity was identified and importantly the modulations were stronger for the observation of incorrect than correct actions. Sources accounting for the difference in beta activity between correct and incorrect actions were localized using a beamforming technique. Both for the execution and observation conditions sources were identified to the dorsal motor areas comprising both primary and pre-motor cortex. Our findings demonstrate that not only is cortical motor activity modulated by action observation, but the modulation increases when the observed action is erroneous. This suggests that the motor system is engaged in evaluating the correctness of the actions of others.

In schizophrenia, disturbances of cognitive control have been associated with impaired functional specialization within the lateral prefrontal cortex (LPFC), but little is known about the functional interactions between specialized LPFC subregions. Here, we addressed this question with a recent model that describes the LPFC functioning as a cascade of control processes along a rostrocaudal axis, whereby anterior frontal regions influence the processing in posterior frontal regions to guide action selection on the basis of the temporal structure of information.

The functional anatomy of Chinese character processing was investigated using fMRI. Right-handed Mandarin-English bilingual participants made either semantic or perceptual size judgements with characters and pictures. Areas jointly activated by character and picture semantic tasks compared to size judgement tasks included the left prefrontal region (BA 9, 44, 45), left posterior temporal, left fusiform, and left parietal regions. Character processing produced greater activation than picture processing in the left mid and posterior temporal as well as left prefrontal regions. The lateral occipital regions were more active during picture semantic processing than character semantic processing. A similar pattern of activation and contrasts was observed when English words and pictures were compared in another set of bilingual participants. However, there was less contrast between word and picture semantic processing than between character and picture processing in the left prefrontal region. When character and word semantic processing were compared directly in a third group, the loci of activation peaks was similar in both languages but Chinese character semantic processing was associated with a larger MR signal change. The semantic processing of Chinese characters, English words, and pictures activates a common semantic system within which there are modality-specific differences. The semantic processing of Chinese characters more closely resembles English words than pictures.

We have previously reported the performance of a patient (NL) who could recognize objects, but appeared to lack knowledge of their orientation. These results were interpreted as evidence that NL had isolated access to a viewpointindependent (ventral stream) object recognition system. However, because NL's responses on naming tasks were not timed, it was not possible to establish whether he showed the same pattern of reaction time performance generally accepted as evidence of a 'mental rotation' strategy in neurologically normal subjects. Here we report NL's performance on two reaction time tasks, testing his ability to transform images when naming, and discriminating between rotated mirror image objects. As predicted, and in contrast to normal volunteers, NL showed no 'mental rotation' effect in his naming of misoriented objects. Paradoxically, he performed well on a traditional Shepard and Metzler mental rotation task. He also showed a normal orientation effect when dealing with misoriented faces. These findings offer further support for viewpoint-independent theories of object recognition, and bolster the claim that object orientation knowledge can be regarded as, in some respects, a special class of spatial information.

Human subjects' answer to questions like "what number is halfway between 2 and 8" provides insights into spatial attention mechanisms involved in numerical processing. Here we show that mental numerical bisections are accompanied by a systematic pattern of horizontal eye movements: processing of a large number followed by a small number is accompanied with leftward eye movements, a tendency less pronounced or even reversed for the processing of a small number followed by a large number. The eyes thus appear to move along a left-to-right-oriented number line, indicating that shifts of attention in representational space are accompanied by an ocular motor orienting response. These results add to the growing evidence for a convergence of numerical processing, spatial attention, and movement planning in the parietal and frontal lobes. They also demonstrate the homologous relationship between our internal representations of numbers and space, and show that the concept of "number space" is more than a mere metaphor.

A complex link exists between vision and unilateral spatial neglect (USN). Firstly, USN is not a perceptual deficit, secondly, USN is not necessarily accompanied by a visual deficit and finally, USN can be observed in non-visual modalities as well as in mental spatial imagery. This apparent supramodality of USN stands in sharp contrast to the fact that neglect signs are often more severe and more durable in the visual than in other sensory modalities (Chokron et al., 2002). The influence of vision on spatial representation has rarely been studied. In the present study we assessed six right brain-damaged patients suffering from left USN on two tasks involving spatial representations: a clock-drawing task and a drawing from memory task in two experimental conditions, with and without visual control. We confirm that even in mental imagery, the absence of visual feedback may decrease and even suppress left neglect signs (Bartolomeo and Chokron, 2001b; 2002). Since vision is largely involved in the orientation of attention in space, suppressing visual control could reduce the magnetic attraction towards the right ipsilesional hemispace and in this way could allow a re-orientation of attention towards the left neglected hemispace. We discuss the theoretical and therapeutic implications of these findings.

Transitions of care pose significant risks for patients with complex medical histories. There are few experiential medical education curricula targeting this important aspect of care. We designed and tested an internal medicine transitions of care experience integrated into interns' ambulatory curriculum. The program included 1-hour group didactics, a posthospitalization discharge visit in pairs with a home care nurse (cohort 1: 2011-2012; cohort 2: 2012-2013), and a half-day small-group visit to a skilled nursing facility led by a faculty member in geriatrics (cohort 2 only). Both visits had structured debriefings by faculty in geriatrics. For cohort 1, a quantitative follow-up survey was administered 18 to 20 months after the experience. For cohort 2, reflections were analyzed. Thirty-three of 42 second-year residents (79%) in cohort 1 who participated in didactics and a home visit completed the survey. Seventy-six percent (25 of 33) reported increased knowledge of interprofes...

We designed a semi-structured questionnaire for the introspective evaluation of inner experience of participants undergoing functional magnetic resonance imaging (fMRI) in the resting state. This resting state questionnaire (ReSQ) consists of 62 items organized by five main types of mental activity: visual mental imagery (IMAG); inner language (LANG), split into two subtypes, inner speech (SPEE) and auditory mental imagery (AUDI); somatosensory awareness (SOMA); inner musical experience (MUSI); and mental manipulation of numbers (NUMB). For IMAG and LANG, additional questions estimated association of such activities with ongoing learning, retrospective memories, or prospective thoughts. Using a 0-100% scale, the participant quantitatively rated the proportion of time spent in each mental activity during the resting state fMRI acquisition. A total of 180 healthy volunteers completed the ReSQ immediately after being scanned with fMRI while at rest. Of these, 66% exhibited dominance of a type of mental activity at rest (IMAG: 35%; LANG: 17%; SOMA: 7%; MUSI: 6%; NUMB: 1%). A majority of participants reported either retrospective memories (82%) or prospective thoughts (78%), with 58% of participants reporting both in at least one type of mental activity. Thoughts related to ongoing learning were low (37% of participants). The present results are consistent with those of previous studies investigating inner experience in a natural environment. In conclusion, we provide a robust and easy-to-implement tool for the exploration of mental activities during rest of healthy participants undergoing fMRI. This tool relies on normative data acquired from a 180-participant sample balanced for sex and handedness.

The objective of this study was to examine differences between fluent English-speaking ethnically diverse (ED) individuals (from Hispanic, Asian and Middle-Eastern descent) and monolingual English-speaking Anglo-Americans (MEAA) on commonly used tests of information processing and attention. A sample of 123 (84 ED and 39 MEAA) healthy individuals participated. The results revealed that the MEAA group outperformed the ED group on Trail Making Test Part B, Stroop B and C, and Auditory Consonant Trigrams (18 s delay condition). Additionally, a host of acculturation variables such as score on a formal acculturation scale, amount of time educated outside of the U.S., and the amount of English spoken when growing up correlated with these various neuropsychological tests. The findings from this study highlight the importance of taking acculturation into account for fluent English-speaking ED individuals when administering and interpreting neuropsychological tests.

OBJECTIVE. The purpose of this study was to examine the predictive relationship of categorization and deductive reasoning abilities to performance of instrumental activities of daily living (IADL) among adults with brain injury. METHOD. A correlational research design was used to examine the performance of 19 patients from a neurosurgery acute care unit on Toglia’s Category Assessment (TCA), the Deductive Reasoning test (DR), and the Observed Tasks of Daily Living–Revised. RESULTS. Multiple regression analysis indicated that categorization and deductive reasoning accounted for a significant proportion of the variance in IADL performance scores, with deductive reasoning making the greater contribution. Demographic characteristics such as age and education reduced the power of the previous variables, especially of the categorization. CONCLUSION. The results of this study indicate that assessments of categorization and deductive reasoning abilities of persons with brain injury may be g...

). The number domain is a prime example where strong evidence points to an evolutionary endowment of abstract domain-specific knowledge in the brain because there are parallels between number processing in animals and humans.The numerical distance effect, which refers to the finding that the ability to discriminate between two numbers improves as the numerical distance between them increases, has been demonstrated in humans and animals, as has the number size effect, which refers to the finding that for equal numerical distance,discrimination of two numbers worsens as their numerical size increases.

In previous papers we proposed that an increase in delta EEG activity during mental tasks might be related to an increase in subjects' attention to internal processing, In this paper we have made a narrow band analysis to detect those EBG frequencies that change selectively during the performance of a mental task that requires attention to internal processing. Two different experiments were performed: (1) a difficult mental calculation task and a control stimulus with the same physical characteristics as the arithmetical symbols were presented in random order; (2) the, Stemberg paradigm for the analysis of short term memory using a memory set of 5 or 3 digits was also presented in random order. Referential recordings to linked ears were obtained in all leads of the lo/20 system. In the ,first experiment, the increase of power from 1.56 to 5.46 Hz was observed only during the performance of the task and not during the control condition. In the Stemberg paradigm, the increase of power from 1.56 to 3.90 Hz was greater during the difficult than during the easy condition. l!hese results support our hypothesis that an increase in delta activity may be related to attention to internal processing during the performance of a mental task. postulated the existence of two kinds, of' behavioral inhibition, both represented by slow waves in the EEG. 'Class I inhibition' would refer to a gross inactivation of an entire excitatory process; resulting in a relaxed, less active state, as in sleep. 'Class II inhibition' would selectively suppress inappropriate or non-relevant neural activity during the performance of a mental task.

A complex link exists between vision and unilateral spatial neglect (USN). Firstly, USN is not a perceptual deficit, secondly, USN is not necessarily accompanied by a visual deficit and finally, USN can be observed in non-visual modalities as well as in mental spatial imagery. This apparent supramodality of USN stands in sharp contrast to the fact that neglect signs are often more severe and more durable in the visual than in other sensory modalities .

Neuroscience is witnessing growing interest in understanding brain mechanisms of memory formation for emotionally arousing events, a development closely related to renewed interest in the concept of memory consolidation. Extensive research in animals implicates stress hormones and the amygdaloid complex as key,interacting modulators of memory consolidation for emotional events. Considerable evidence suggests that the amygdala is not a site of long-term explicit or declarative memory storage, but serves to influence memory-storage processes in other brain regions, such as the hippocampus, striatum and neocortex. Human-subject studies confirm the prediction of animal work that the amygdala is involved with the formation of enhanced declarative memory for emotionally arousing events.

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Disorders in verbal and emotional communication and imitation, social reciprocity and higher-order cognition observed in individuals with Autism Spectrum Disorders (ASD) are presented here as phenotypic expressions of Temporo-Spatial Processing Disorders (TSPD). TSPDs include various degrees of disability in i) processing multi-sensory stimuli online, ii) associating them into meaningful and coherent patterns and iii) producing real-time sensorymotor adjustments and motor outputs. In line with this theory, we found that slowing down the speed of facial and vocal events enhanced imitative, verbal and cognitive abilities in some ASD children, particularly those with low functioning autism. We then argue that TSPDs may result from Multi-system Brain Disconnectivity-Dissynchrony (MBD), defined as an increase or decrease in functional connectivity and neuronal synchronization within/between multiple neuro-functional territories and pathways. Recent functional magnetic resonance imaging (fMRI) and electrophysiological studies supporting MBD are outlined. Finally, we review the suspected underlying neurobiological mechanisms of MBD as evidenced in neuroimaging, genetic, environmental and epigenetic studies. Overall, our TSPD/MBD approach to ASD may open new promising avenues for a better understanding of neuro-physio-psychopathology of ASD and clinical rehabilitation of people affected by these syndromes.

Verbal fluency was operationalized as the number of words produced in a restricted category (i.e., semantic category [SCF] and words beginning with a given letter [ILF]) in 60 seconds. Word production in the first 15 seconds of either type of fluency task was defined as a measure of automatic information processing, whereas word production in the remaining 45 seconds (in 15-second periods) was taken as a measure of controlled information processing. Data revealed that over 60 seconds healthy children aged 8.4-9.7 years (n = 91) produced significantly more words and less incorrect responses on the SCF task than on the ILF task. Although word production was a function of both type of task and time, it was highest in the initial time slice of either type of fluency and decreased as time on task increased. Finally, no sex differences were found for any measure of performance on either type of fluency task. In contrast, the level of occupational achievement of the caregiver (LOA) appeared to be a determinant of the child's performance on either type of fluency task, indicating that LOA affects higher-order processes, such as the automation of newly learned verbal skills and effortful processing.

A review of the field of lightness perception from Helmholtz to the present shows the most adequate theories of lightness perception to be the intrinsic image models. Nevertheless, these models fail on 2 important counts: They contain no anchoring rule, and they fail to account for the pattern of errors in surface lightness. Recent work on both the anchoring problem and the problem of errors has produced a new model of lightness perception, one that is qualitatively different from the intrinsic image models. The new model, which is based on a combination of local and global anchoring of lightness values, appears to provide an unprecedented account of a wide range of empirical results, both classical and recent, especially the pattern of errors. It provides a unified account of both illumination-dependent failures of constancy and background-dependent failures of constancy, resolving a number of longstanding puzzles. We present a new theory of how the visual system assigns lightness values-or perceived black, white, or gray values-to various regions of the retinal image. The theory grew out of two problems facing what are probably the most advanced models of lightness perception: the intrinsic image models.

Among 30 Hong Kong Chinese fourth graders, sensitivities to character and word constructions were examined in judgment tasks at each level. There were three conditions across both tasks: the real condition, consisting of either actual two-character compound Chinese words or real Chinese compound characters; the reversed condition, with either the order of the two morphemes in the word or the order of the semantic and phonetic radicals in the character reversed; and the random condition, with either two morphemes randomly combined to create arbitrary nonwords or a semantic radical and a phonetic radical randomly combined using correct orthographic rules to create noncharacters. On the word level, children performed worst in the reversed condition and best with real words, whereas on the character level, children performed worst in the random condition and best in the reversed condition. Findings imply a holistic tendency toward word-level processing and an analytic approach to character-level processing in these Chinese children.

Previous findings suggest that planning an action "backward-primes" perceptual dimension related to this action: planning a grasp facilitates the processing of visual size information, while planning a reach facilitates the processing of location information. Here we show that dimensional priming of perception through action occurs even in the absence of active action planning. Subjects watched video clips showing a grasping or reaching action before detecting size-or location-defined deviants in visual stimulus sequences. Size deviants were detected faster after seeing a grasp and location deviants were detected faster after seeing a reach. This supports the assumption that perceptual codes and action plans share a common representational medium, and that "attention to action" controls "attention to stimuli".

We measured cerebral activation with functional magnetic resonance imaging at 3 Tesla while eight healthy volunteers performed various number processing tasks known to be dissociable in brain-lesioned patients: naming, comparing, multiplying, or subtracting single digits. The results revealed the activation of a circuit comprising bilateral intraparietal, prefrontal, and anterior cingulate components. The extension and lateralization of this circuit was modulated by task demands. The intraparietal and prefrontal activation was more important in the right hemisphere during the comparison task and in the left hemisphere during the multiplication task and was intensely bilateral during the subtraction task. Thus, partially distinct cerebral circuits with the dorsal parietal pathway underlie distinct arithmetic operations.

Evidence from a large-scale study of 11-year olds in Britain suggests that ambidextrous individuals may be disadvantaged in tests of verbal, nonverbal, reading, and mathematical skills relative to right-and left-handers, but this basic finding was not replicated in another study of younger boys in Germany. Here, we present data based on a television show in which members of the public were given an IQ test. Some individuals were also asked to state whether they wrote with the left hand, right hand, or either hand. The data support the earlier finding that ambidextrous individuals perform more poorly than left-or right-handers, especially on subscales measuring arithmetic, memory, and reasoning, and extend that finding to adults.

Cognitive psychology attempts to understand the nature of the human mind by using the information-processing approach. In this article, the fundamentals of the cognitive approach will be presented. It will be argued that the human mind can be described at three levels-computational, algorithmic-representational, and implementational-and that the cognitive approach has both important theoretical and practical/clinical implications. Finally, it will be suggested that the study of cognitive psychology can provide a foundation for other fields of social science, including the field of clinical psychology.

Activity theory has been successfully applied in diverse schools of psychology with particularly extensive work in the fields of education, ergonomics, human factors and industrial-organizational psychology. However, existing efforts of translation and formulation in English suffer from certain limitations. These limitations include the blurring between Vygotsky's sociocultural theory of the development of mind and activity theory, the restriction of activity theory in its entirety to the version offered by Leont'ev, errors in the interpretation of some basic concept and terminology, reliance on studies that use obsolete methods, and failure to consider the Russian work in activity theory in its entirety. This last problem results in the omission of the recent advances in engineering psychology and educational psychology in the former Soviet Union that facilitates the application of activity theory to practical problems. This paper is a description of the evolution of basic theory, concepts and terminology relevant to practitioners-particularly in the field of ergonomics.

Social phobia is a persistent disorder that is unlikely to be maintained by avoidance alone. One reason for the enduring nature of social phobia may be the way individuals with the disorder process social information. It is important for those involved in social phobia to have an understanding of information-processing biases, because it has the potential to guide psychological interventions.

Research has not resolved whether depression is associated with a distinct information-processing bias, whether the content of the information-processing bias in depression is specific to themes of loss and sadness, or whether biases are consistent across the tasks most commonly used to assess attention and memory processing. In the present study, participants diagnosed with major depression, social phobia, or no Axis I disorder, completed several information-processing tasks assessing attention and memory for sad, socially threatening, physically threatening, and positive stimuli. As predicted, depressed participants exhibited specific biases for stimuli connoting sadness; social phobic participants did not evidence such specificity for threat stimuli. It is important to note that the different measures of bias in memory and attention were not systematically intercorrelated. Implications for the study of cognitive bias in depression, and for cognitive theory more broadly, are discussed.

Primary objective: This study investigated whether cognitive impairment after traumatic brain injury (TBI) can be considered a consequence of (1) a speed processing deficit or (2) an impairment of the Central Executive System (CES) of working memory. Methods and procedures: Thirty-seven TBI patients underwent a standardized battery of neuropsychological tests evaluating speed processing, sustained attention, short-term memory, working memory, divided attention, executive functions and long-term memory. Main outcomes and results: Patients showed severe deficits in working memory, divided attention, executive functions and long-term memory. Divided attention, long-term memory and executive functions deficits significantly correlated with working memory, but not with speed processing deficits. Moreover, multiple regression analyses showed that a CES impairment and not a speed processing deficit predicted divided attention, executive functions and long-term memory deficits. The severity and the site of brain lesions did not predict the level of CES or speed processing impairment. Conclusions: The cognitive impairment following TBI seem to be caused by an impairment of the Central Executive System, rather than a speed processing deficit. (1): 23-32 Patients were selected for participating in the study if they complained of lack of attention, poor memory or loss of efficiency in everyday life. Exclusion criteria were prior history of TBI or other 24 A. Serino et al.

A growing body of data suggests that the emotional dimension of a stimulus can be processed without conscious identification of the stimulus. The arousal system could be activated by unrecognised biologically significant stimuli through simple physical stimulus features related to threat, without any evaluation of the meaning of the stimulus. However, unconscious processing of emotionally laden words cannot rely only

It is commonly accepted that phonology is the exclusive domain of the left hemisphere. However, this pattern of lateralization, which posits a right visual field advantage, has been questioned by several studies. In fact, certain factors such as characteristics of the stimuli and subjectsÕ handedness can modulate the right visual field advantage. Thus, the goal of this study was to compare the hemispheric dynamics of right-handers and left-handers during a divided visual field presentation of words that varied in terms of their phonological transparency. For non-transparent words, the left hemisphere seems more competent in both handedness groups. With regard to transparent words, the right hemisphere of both groups also appears competent. Surprisingly, left-handers achieved optimal processing with a functionally isolated left hemisphere, whereas right-handers needed the participation of both hemispheres. The pattern of performance cannot be fully explained by either the callosal or the direct access model.

We investigated the e¡ects of cortical stimulation on mental rotation tasks in a patient with an electrode array placed over his left primary motor cortex.The array was implanted to relieve chronic pain resulting from right brachial plexus damage. Tasks involving motor imagery were slowed down by cortical stimulation, whereas those involving visual imagery were not. When the patient performed the motor-imagery task, the interference effect on response times disappeared if the stimulator was switched o¡.We also probed two of the sites (anterior-lateral and posteriormedial position), and found that stimulation of the more anteriorlateral one consistently disrupted motor imagery. NeuroReport 16:1795^1800

The effect of different carbohydrate to protein ratios in food on cognitive functions and the relation between postprandial metabolic and cognitive changes were studied in 15 healthy male students. Subjects were tested in three sessions, separated by 1 week, for short-term changes in mood states, objective cognitive functions, blood parameters, and indirect calorimetry using a repeated-measures, counterbalanced cross-over design. Measurements were made after an overnight fast before and hourly during 3.5 h after test meal ingestion. The isoenergetic (1670 kJ) test meals consisted of three carbohydrate to protein ratios, i.e. a carbohydrate-rich (CHO[4:1]), balanced (BAL[1:1]), and protein-rich (PRO[1:4]) meal, respectively. Overall accuracy in short-term memory was best after the PRO[1:4] meal concomitant to the least variation in glucose metabolism and glucagon to insulin ratio (GIR). Related to changes in glucose metabolism and/or in the ratios of large neutral amino acids (LNAA),...

Ketamine is an N-methyl-D-aspartate (NMDA) receptor antagonist with prominent psychoactive effects in humans. This study evaluated whether the oral administration of haloperidol 5 mg would block the effects of an intravenous ketamine infusion (bolus of 0.26 mg/kg followed by 0.65 mg/kg per hour). Twenty healthy subjects completed 4 test days involving the oral administration of haloperidol or matched placebo 2 h prior to the intravenous infusion of ketamine or saline. Ketamine produced cognitive, behavioral, neuroendocrine, and physiologic effects in the healthy subjects that were similar to previous reports. Haloperidol pretreatment reduced impairments in executive cognitive functions produced by ketamine as measured by proverb interpretations and the Wisconsin Card Sorting Test. However, it failed to block the capacity of ketamine to produce psychosis, perceptual changes, negative symptoms, or euphoria in healthy subjects. These data outline an important, but functionally delineaeted modulation of ketamine effects by dopamine2 receptors and other sites of haloperidol action.

Ten healthy men were tested at 0600, 1200, 1800 and 2400 hours on different days at rest in a laboratory at room temperature followed by 1 h of heat exposure in a climatic chamber at 42 ° C, 60% rh (50 min rest and 10 min exercise on a cycle ergometer at 50% lkO2max). Heart rate, blood pressure, rectal temperature Try, metabolic rate, number connection test, visual and auditory reaction time, flicker test and catecholamine excretion were measured. Heat exposure and exercise caused lower heart rate acceleration at 2400 hours than at 0600 and 1200 hours, the smallest increase of Tr~ at 1800 hours, and an increase in metabolic rate greater at 1200 than at 1800 hours. In the afternoon, when, according to the circadian rhythm, the body temperature is highest, the additional heat load produced the smallest physiological effects. Performance efficiency, after heat exposure combined with physical exercise, improved slightly, but diurnal variations did not show significant circadian rhythm.

This study investigated differences in cognitive processes related to problem complexity. It was assumed that these differences would be reflected in respondents' EEG activity--spectral power and coherence. A second issue of the study was to compare differences between the lower (alpha(1) = 7.9-10.0 Hz), and upper alpha band (alpha(2) = 10.1-12.9 Hz). In the first experiment two well-defined problems with two levels of complexity were used. Only minor differences in EEG power and coherence measures related to problem complexity were observed. In the second experiment divergent production problems resembling tasks on creativity tests were compared with dialectic problems calling for creative solutions. Differences in EEG power measures were mainly related to the form of problem presentation (figural/verbal). In contrast, coherence was related to the level of creativity needed to solve a problem. Noticeable increased intra- and interhemispheric cooperation between mainly the far distant brain regions was observed in the EEG activity of respondents while solving the dialectic problems. These results are explained by the more intense involvement of the long cortico-cortical fiber system in creative thinking. Differences between the lower and upper alpha band were significant for the power and coherence measures. In Experiment 2, fewer differences were observed in power measures in the upper alpha band than in the lower alpha band. A reverse pattern was observed for the coherence measures. These results hint to a functional independence of the two alpha bands, however, they do not allow to draw firm conclusions about their functional meanings. The study showed that it is unlikely that individuals solve well- and ill-defined problems by employing similar cognitive strategies.