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A series of studies with children in Grades 1-4 inquired into the immediate and historical determinants of a preference for analytic conceptual groupings. An analytic concept is based upon shared similarity in a particular objective component among a set of stimuli (e.g., animals with 1 car, people with hats on). Results revealed that 2 more fundamental cognitive dispositions each contributed variance to the production of analytic concepts: the tendency to reflect over alternative solutions or classifications in situations in which several response alternatives arc available simultaneously, and the tendency to analyze visual arrays into their component parts. These 2 dispositions are relatively independent of each other, orthogonal to verbal skills; and each influences the frequency of errors in perceptual recognition tasks. Degree of reflection over alternative solution hypotheses (as measured by response time) displayed remarkable generality across a variety of tasks and marked intraindividual stability over a 1-yr. period. There was an inverse relation between the production of analytic concepts and extreme degrees of hyperactivity and distractibility contemporaneously as well as during the 1st 8 yr. of life.Problem solving involves at least three distinct processes that occur in the following sequence: the initial categorization of information, storage of the encoded information, and the imposing of transformations or mediational elaborations upon the encoded material. The form of the initial categorization, transformation, or mediation is governed, of course, by the nature of the problem. Students of cognitive development have generally assumed that the striking differences between the cognitive products of children of different ages (or among children of the same age) were due primarily to differences in the availability of a classification vocabulary, transformation rules, and mediational diversity. In ellect, the superior problem solving performance of older, in contrast to younger, children has

Cognitive neuroscience provides a new conceptual framework for psychiatry by showing how psychological processes arise from neuronal activity (Kandel 1998). Conversely, it is possible that psychiatry will influence the future development of cognitive neuroscience by encouraging a better balance between localist and holistic conceptions of brain function. An apparent conflict between these conceptions has been central to the development of neuroscience, with the emphasis upon locally specialized functions emerging as clearly dominant. Neuroanatomy, neurophysiology, neuropsychology, and neuroimaging all show that different regions of the brain process information about different things, and that different cells within regions deal with different aspects of those things. Recent developments in experimental and theoretical neurobiology, however, are leading to an increased emphasis upon interactions that coordinate the activity of locally specialized processors. Here we argue that impairment of these coor-BEHAVIORAL AND BRAIN SCIENCES (2003) Abstract:The concept of locally specialized functions dominates research on higher brain function and its disorders. Locally specialized functions must be complemented by processes that coordinate those functions, however, and impairment of coordinating processes may be central to some psychotic conditions. Evidence for processes that coordinate activity is provided by neurobiological and psychological studies of contextual disambiguation and dynamic grouping. Mechanisms by which this important class of cognitive functions could be achieved include those long-range connections within and between cortical regions that activate synaptic channels via NMDAreceptors, and which control gain through their voltage-dependent mode of operation. An impairment of these mechanisms is central to PCP-psychosis, and the cognitive capabilities that they could provide are impaired in some forms of schizophrenia. We conclude that impaired cognitive coordination due to reduced ion flow through NMDA-channels is involved in schizophrenia, and we suggest that it may also be involved in other disorders. This perspective suggests several ways in which further research could enhance our understanding of cognitive coordination, its neural basis, and its relevance to psychopathology.Keywords: attention; cerebral cortex; cognitive coordination; cognitive neuropsychiatry; cognitive neuropsychology; context disorganization; Gamma rhythms; Gestalt theory; glutamate; grouping; memory; NMDA-receptors; PCP-psychosis; perceptual organization; schizophrenia William A. Phillips, Ph.D., is Professor of Neuropsychology at the University of Stirling, Scotland UK. He has published more than 70 papers on vision, visual memory, perceptual learning, childrens drawings, the effects of brain damage on reading and writing, and the theory of neuronal computation. He was a founder and the first Director of the Center for Cognitive and Computational Neuroscience at the University of Stirling.Steven M. Silverstein, Ph.D., is A...

Abstract:It is worthwhile to search for forms of coding, processing, and learning common to various cortical regions and cognitive functions. Local cortical processors may coordinate their activity by maximizing the transmission of information coherently related to the context in which it occurs, thus forming synchronized population codes. This coordination involves contextual field (CF) connections that link processors within and between cortical regions. The effects of CF connections are distinguished from those mediating receptive field (RF) input; it is shown how CFs can guide both learning and processing without becoming confused with the transmission of RF information. Simulations explore the capabilities of networks built from local processors with both RF and CF connections. Physiological evidence for synchronization, CFs, and plasticity of the RF and CF connections is described. Coordination via CFs is related to perceptual grouping, the effects of context on contrast sensitivity, amblyopia, implicit influences of color in achromotopsia, object and word perception, and the discovery of distal environmental variables and their interactions through self-organization. Cortical computation could thus involve the flexible evaluation of relations between input signals by locally specialized but adaptive processors whose activity is dynamically associated and coordinated within and between regions through specialized contextual connections.

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