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Evaluation of a Neural Network Model of Amnesia in Diffuse Cerebral Atrophy

Published online by Cambridge University Press:  02 January 2018

James R. G. Carrie*
Affiliation:
Department of Psychiatry and Behavioral Sciences, Baylor College of Medicine, and Psychiatry Service, Houston VAMC, 2002 Holcombe, Houston, Texas 77030, USA

Abstract

A digital computer program generating a simulated neural network was used to construct a model which can show behaviour resembling human associative memory. The experimental network uses distributed storage, and, in this respect, its functional organisation resembles that suggested by reported observations of neuronal activity in the human temporal lobe during memory storage and recall. Inactivation of increasing numbers of randomly distributed network units simulated advancing cerebral atrophy. This caused progressive impairment of performance, resembling the gradual deterioration of memory function observed in chronic diffuse cerebral degeneration. Unit inactivation had similar effects on recall whether the same units were inactivated before or after learning. This differs from most relevant observations of amnesia resulting from diffuse cerebral disease. While the model may functionally resemble long-term information storage sites in the brain, other cerebral mechanisms participating in learning and remembering are also damaged by diffuse cerebral atrophy.

Type
Research Article
Copyright
Copyright © Royal College of Psychiatrists, 1993 

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