[Methods for assessing cognitive function utilizing operant tasks in rats].

Abstract

Most human behaviors (responses) are volitional, the frequency of which is changed based on stimulus presentations contingent upon the response, that is, operant behavior. It is considered that the findings on cognitive functions based on operant behaviors are more reliable in extrapolating the results to humans. Impairment of memory function, most notably the impairments of working memory and attention, is an important research focus to elucidate the mechanism underlying the core syndrome of Alzheimer's disease. Among various methods to measure working memory and attention, a delayed matching-to-sample paradigm utilizing operant chambers equipped with 3 levers and a choice reaction time paradigm have been proven to be very useful. Aside from these, adaptation to new environment is an important function for survival, and its impairment has been considered to be one of the factors inducing psychiatric disorders. Preclinical methods to measure the adaptation ability include a position reversal learning paradigm utilizing 2-lever operant chambers. Since the findings of studies on cognitive functions utilizing operant behaviors have been in good correlation with clinical findings, it would serve as a good strategy for elucidating the causes of such disorders as well as developing therapeutic agents.