May 06, 2004

"FUNCTIONAL COGNITIVE NETWORKS IN PRIMATES".

by J. Wesson Ashford, M.D., Ph.D., Kerry L. Coburn, Ph.D., Joaquin M. Fuster, M.D., Ph.D

Chapter 2 in: FUNDAMENTALS OF NEURAL NETWORK MODELING FOR NEUROPSYCHOLOGY eds: Randolph W. Parks, Ph.D., Psy.D. Daniel S. Levine, Ph.D. Debra L. Long, Ph.D. The MIT Press. Cambridge, Massachusetts. 1998.
Pages 33-60.

Quoted:

"II. BUILDING BLOCKS OF THE NERVOUS SYSTEM

Several basic principles of nervous system evolution form the basis for understanding higher primate brain function (Jones, 1990). The adaptive sequence from sensation of the environment to initiation of reflexive movement is the fundamental operation that the nervous system provides. Neural pathways have developed redundant and parallel channels to assure the reliability and fidelity of transmitted information, as well as to increase the speed and reliability of processing. Neurons and neural networks also have developed means for abstracting, retaining, and later retrieving information - the basic time-spanning operations of memory. Progressively more complex levels of analysis form a hierarchy, with higher levels of neurons and networks performing progressively more complex information analyses and more refined response productions (Hayek, 1952). However, there is one simple principle: the more neurons involved in processing, the more complex the potential analysis of the information (Jerison, 1991). But, a larger number of neurons also has a larger energy cost that must be born by the organism and species, and hence must have a cost-benefit justification. Further, there is a need for both functional specialization ("low-level", routine operations; e.g., analysis of line orientation or color) and generalization (e.g., determining abstract relations between stimuli) of networks. The evolutionary balance along this dimension has given rise to the rich diversity of fundamental neural systems that are present in the brain, and the evolutionary refinement of cortical processing through the primate lineage has achieved extraordinary power in the human brain."

Hayek, F. A. (1952) The Sensory Order: An inquiry into the foundations of theoretical psychology. Chicago: The University of Chicago Press.

Posted by Greg Ransom at May 6, 2004 12:16 AM | TrackBack
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