PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “CONDITIONED REFLEX”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 217 records · Page 12Linked to original sources
PubMedDate not supplied

[Organization of integrated systems of conditioned reflexes in dogs with a damaged temporal cortex].

By means of the classical alimentary secretory method, a study was made of the characteristics of formation and preservation of complex systems of conditioned reflexes in dogs with a preliminarily lesioned cortex of the auditory analyser. It has been shown that a rhythmic-mozaic stereotype of conditioned reflexes to acoustic signals can be elaborated in the operated dogs, although conditioned activity is on a very low functional level. However, integration of two complex stereotypes into one single system is not achieved. The formation of a new stereotype in the operated dogs, in contrast to the intact animals, is not accompanied by an enhanced functional state (tone) of the brain, which points to an insufficiency of the self-regulating mechanisms of the cerebral cortex. It is suggested that special activating mechanisms which participate in controlling the functional state of the auditory system, are present in the cortical structures of the auditory analyser.

Animals↗
PubMedDate not supplied

Does heart rate differentiate neurotic from normal people in a conditional reflex test?

This study is to compare heart reactivity between normals and anxiety neurotic patients. Five male and five female patients with anxiety neurosis and four male and five female normal persons were submitted to classic delayed conditional reflexes with different probabilities of reinforcement (shock), to a defensive instrumental conditional reflex, and to a neutral nonreinforced stimulus. The basal heart frequency was higher in neurotics and in women than in normals and men. The conditional stimulus (CS) associated with a shock generally produced a bradycardia in normal individuals and in neurotic men, but a tachycardia in neurotic women (effects most pronounced in cases with 100% shock probability). The instrumental CS caused a tachycardia in all of the groups, with highest values in neurotic women. The neutral stimulus produced bradycardia in all persons. The aftereffect of the light stimulus depended on whether a shock was administered and on the CS. The differences between neurotics and normals are explained as caused by the heightened excitatory level of the CNS of the neurotic group, produced by the unspecific activating effect of chronic anxiety, and differences of plastic processes in both groups, resulting in different effects of phasic anxiety on the heart. Complex inhibitory-excitatory interactions of the sympathetic and the vagal system underlying the heart rate changes may be assumed. Possible mechanisms leading to sex differences are discussed.

Adult↗
PubMedDate not supplied

[Disruptions of instrumental alimentary conditioned reflexes after removal of the frontal and parietal associative cortex in the cat].

The influence of the extirpation of the frontal and parietal association cortical areas on the elaborated stereotype of instrumental alimentary conditioned reflexes was studied in cats. Errors in reinforcement choice, disturbance of inhibitory conditioned reflexes and appearance of intersignal reactions were observed. The disturbances were more pronounced after the extirpation of the parietal cortex. The data obtained are interpreted as a reflection of the deficit of the inhibitory control of motor program realization formed to a lesser or greater extent after the removal of the frontal as well as parietal areas.

Animals↗
PubMedDate not supplied

[Effect of coagulation of different regions of the hippocampus on elaboration and preservation of conditioned reflexes].

A study was made in rats of the influence of coagulating the anterior and posterior dorsal, medial and ventral hippocampus on the formation and preservation of electro-defensive and food-procuring conditioned reflexes. Statistical processing of the experimental data by the Student t-criterion showed that coagulation of these hippocampal areas does not influence the formation or preservation of the food-procuring reflex. Coagulation of the anterior dorsal and ventral hippocampus does not affect electro-defensive conditioned reflexes. Coagulation of the posterior dorsal and medial hippocampus delays the elaboration of electro-defensive reflexes and to a lesser extent influences their preservation.

Animals↗
PubMed1987

[Effect of thymalin on protein synthesis in the brain and conditioned-reflex activity of the progeny of neurosensitized female rats].

Thymalin administration to two-week-old offspring of neurosensitized female rats prevented the development of protein synthesis disturbances in the central nervous system and the retention of conditioned reflex of passive avoidance. Thymalin injection to the offspring of intact female rats improved conditioned reflex retention and did not affect brain protein synthesis. A possible mechanism of thymalin effect in conditions of congenital neuroimmunopathology is discussed.

Adjuvants, Immunologic↗
PubMedDate not supplied

[Effect of electric stimulation of the parietal cortex on alimentary conditioned reflexes in dogs].

Changes in elaborated alimentary secretory reflexes were studied in dogs during bilateral electrical stimulation of the parietal cortex. It was found that a low-frequency (1 imp/s) continuous stimulation with subthreshold rectangular current exerts predominantly an inhibitory influence: on the beginning of stimulation, the spontaneous secretion and the secretion at intervals between the conditioned reflexes diminish, the latencies of conditioned reactions become longer, the conditioned secretion is reduced; at the same time unconditioned reflexes are retained and there is a tendency to their increase. High frequency (100 imp/s) stimulation with the same current is attended with an increase of conditioned, unconditioned and spontaneous secretion; however the latencies of conditioned reflexes are increased. Stimulation of the right hemisphere, contralateral to the side of secretion recording, exerts a more pronounced influence on the conditioned alimentary reflexes than that of the ipsilateral hemisphere.

Animals↗