Stimulation of Cognitive Abilities in Aged Macaques via Moderate Hypobaric Hypoxia

Abstract

The importance of research on neurological and mental changes in aged nonhuman primates, in particular, rhesus macaques (Macaca mulatta), is due to their genetic and physiological similarity with humans, which makes them preferable to rodents in preclinical studies of age-dependent cognitive decline correction. In this paper, we study the behavior of three older monkeys in solving a conditioned reflex task of image differentiation. The obtained values of several cognitive characteristics were compared with those determined for the same subjects in their youth more than 15 years ago. It is shown that aging in the experimental monkeys solving the cognitive tasks was accompanied by an increase in the number of errors, decision time, and events of refusal to work, as well as by weakening of the spatial working memory, which was estimated by the method of “delayed response.” The procedure of three repeated 2-h sessions of moderate hypobaric hypoxia at 360 mmHg significantly improved these characteristics. The cognitive status, as corrected by moderate hypoxic stress, significantly approached the cognitive level possessed by these subjects in youth. This positive effect was maintained for 2–6 months.