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abstract: 'The span of complexity in brains, between the simplest flatworms and the most advanced mammals is exceedingly great, measured by the number of different anatomical parts, physiological processes, sensory discriminations, and behavioral alternatives in the repertoire. Most evolution of brains has been adaptive radiation within the same grade of complexity. Distinct grades of complexity have appeared a dozen or more times and quite often in the retrograde direction. Advancement has not been inevitable or obviously advantageous in survival value but has happened - long before primates or mammals or vertebrates. Compare cuttlefish and the most advanced gastropods, bees and the best brine shrimp, primates and the most advanced reptiles known - all twigs with common branches. This repeated achievement of evolution has had all too little study in respect of the detailed listing of differences between major taxa of distinct grades of complexity. Connectivity at the level now known for the mammalian cortex is much needed in other classes, with estimates of reciprocity, intrinsic differentiation, dendritic parcellation and afferent and efferent connections, both locally and projecting to other centers, each done quantitatively to permit comparison. Physiological system organization, personality properties of neurons and circuits, proclivities and emergent phenomena at several integrative levels are sketchily known only for parts of a few systems. Examples are given of opportunities for new research that can more adequately characterize grades of brains.'
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given: TH
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date: 2002
date_type: published
datestamp: 2002-11-08
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keywords: 'Neuroscience, neural complexity, neurology'
lastmod: 2011-03-11 08:55:05
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number: 4
pagerange: 317-329
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publication: Integrative And Comperative Biology
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Bullock, T. H., McClune, M. C. and J. Z. Achimowicz. 1995c. EEG coherence as a measure of synchrony shows fine structure in space and time. Abstr. of the Fourth IBRO World Cong. of Neurosci., Kyoto, Japan. p 494
Bullock, T. H., Achimowicz, J. Z., Duckrow, R. B., Spencer, S. S. and V. J. Iragui-Madoz.1997. Bicoherence of intracranial EEG in sleep, wakefulness and seizures. Electroencephalogr. Clin. Neurophysiol. 103:661-678.
Felleman, D J; and D.C. Van Essen 1991 Distributed hierarchical processing in the primate cerebral cortex. Cerebral Cortex, 1 :1-47
Stephan, K. E., Kamper, L., Bozkurt, A., Burns, G. A. P. C., Young, M. P., and R. Koetter 2001 Advanced database methodology for the Collation of Connectivity data on the Macaque brain (CoCoMac). Phil. Trans. Roy. Soc., London B 356 (1412): 1159- 1186.
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status_changed: 2007-09-12 16:45:53
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- neuro-physio
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title: 'Grades in neural complexity: how large is the span?'
type: journalp
userid: 479
volume: 42