title: The neocortical circuit: themes and variations.
abstract: Similarities in neocortical circuit organization across areas and species suggest a common strategy to process diverse types of information, including sensation from diverse modalities, motor control and higher cognitive processes. Cortical neurons belong to a small number of main classes. The properties of these classes, including their local and long-range connectivity, developmental history, gene expression, intrinsic physiology and in vivo activity patterns, are remarkably similar across areas. Each class contains subclasses; for a rapidly growing number of these, conserved patterns of input and output connections are also becoming evident. The ensemble of circuit connections constitutes a basic circuit pattern that appears to be repeated across neocortical areas, with area- and species-specific modifications. Such 'serially homologous' organization may adapt individual neocortical regions to the type of information each must process.
authors.affiliation: UCL Institute of Neurology and UCL Department of Neuroscience, Physiology, and Pharmacology, University College London, London, UK.
authors.forename: Kenneth D
authors.initials: KD
authors.lastname: Harris
authors.affiliation: Department of Physiology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, USA.
authors.forename: Gordon M G
authors.initials: GM
authors.lastname: Shepherd
mesh_terms: D000818:Animals; D006801:Humans; D007395:Interneurons / Q000502:physiology*; D019579:Neocortex / Q000166:cytology* / Q000502:physiology; D009415:Nerve Net / Q000166:cytology* / Q000502:physiology