ABSTRACT
On complex behavioural model (preference reaction), studies have been made of the effect of stimulation of two different hypothalamic nuclei, i.e. ventromedial and mammillary ones, on the conditioned reflex activity in cats. It was shown that stimulation of the ventromedial nucleus (in contrast to that of the mammillary one) exerts more complex differentiated effect on the higher nervous activity. Similar effect may be induced by subcutaneous administration of beta-endorphin. The data obtained are discussed in relation to the development of two different mechanisms of hypothalamic influence on neocortical activity.
Subject(s)
Cerebral Cortex/physiology , Hypothalamus/physiology , Predatory Behavior/physiology , Acoustic Stimulation , Animals , Cats , Chi-Square Distribution , Conditioning, Classical/drug effects , Conditioning, Classical/physiology , Electric Stimulation , Electroencephalography , Feeding Behavior/drug effects , Feeding Behavior/physiology , Higher Nervous Activity/drug effects , Higher Nervous Activity/physiology , Predatory Behavior/drug effects , Reaction Time/drug effects , Reaction Time/physiology , Stimulation, Chemical , beta-Endorphin/pharmacologyABSTRACT
The role of beta-endorphin in the regulation of conditioned instrumental food-procuring reactions and more complex forms of nervous activity such as reflexes of choice of the side of reinforcement was studied in cats. It was established that the subcutaneous injection of small doses of beta-endorphin (10 micrograms/kg, 15 x 10(-6) micrograms/kg) exerts a facilitatory nonspecialized effect on positive and negative food-procuring conditioned reflexes that has an overall adaptive character overall. The influence of the same doses of beta-endorphin on conditioned reflexes of choice is more complex in character, depending upon the initial level of conditioned reflex activity and on the typological features of the experimental animals. A possible mechanism of the influence of beta-endorphin on higher nervous activity is discussed.
Subject(s)
Conditioning, Classical/physiology , beta-Endorphin/physiology , Animals , Behavior, Animal/drug effects , Cats , Dose-Response Relationship, Drug , Injections, Subcutaneous , beta-Endorphin/administration & dosage , beta-Endorphin/pharmacologyABSTRACT
The role of beta-endorphin in regulation of instrumental food conditioning and in more complicated forms of nervous activity in cats was found to involve a facilitating unspecific effect both on positive and negative food conditioning, the latter having a general adaptive character. The influence of the same small doses of beta-endorphin (10 mkg/kg - 15 x 10(-6) mkg/kg) on the choice responses was more complicated and depended on the basic level of conditioning and the typology of animals. Possible mechanism of the beta-endorphin effect on higher nervous activity, is discussed.
