THE MOBILITY OF NERVOUS PROCESSES IN DOGS OF DIFFERING AGES, WHICH HAD PREVIOUSLY BEEN EXPOSED TO IONIZING RADIATION IN UTERO

Journal Article · Mon Jan 01 04:00:00 EST 1962 · Zh. Vysshei Nervnoi Deyatel'nosti im. I.P. Pavlova

OSTI ID:4704417

Ayrapetyants, M G

>Pregnant bitches were exposed to total-body radiation by means of a single dose of 200 r. Nine of their puppies were used for the experiments and 9 healthy puppies served as thc control group. Conditioned reflexes based on local and general motor responses were established at the age of 2 months and the mobility of the nervous processes was tested by reversing the signals, so that the formerly positive signal now became the negative signal and vice versa. At the age of 1 year the classical alimentary conditioned reflex based on salivation was established and the signals were again reversed. This test was repeated at the age of 1.5 years but now the task was facilitated by the introduction of a regular pattern with the formerly positive, and now negative stimulus always preceding the formerly negative (now positive) stimulus. It had earlier been shown by M. K. Petrova that such regular patterns enabled castrated dogs to cope with complex tasks, normally beyond their capacity. In both the experimental and the control dogs the reflex response to the buzzer underwent 3 consecutive phases. During the initial orientation reflex' consisting of a diffuse motor reaction, the response to the positive stimulus became less marked and the dogs were unable to recognize the differential signal, almost completing the reverse response to the signal given. This phase persisted in the irradiated dogs for 2 to 3 days but in the control group it happened oniy in a single experiment. In the second phase, the response corresponded to the previous, now reversed, meaning of the stimulus applied. This stage lasted 6 to 7 days in the irradiated and only 2 to 3 days in the control dogs. The intensity of the response in the experimental group showed sudden variation, from maximal explosions' to complete apathy or sleepiness, suggestive of a task outside the limits of the animals' capacity. The beginning of the third phase was marked by the first correct response to the new meaning of the reversed stimulus. This occurred after 8 to 9 days in the experimentai group and after 3 to 4 days in the control group. In the latter group complete reversal was achieved, i.e., every stimulus was followed by the new, correct response. This could never be achieved in the irradiated dogs. The findings were the same for all age groups in question. Dogs irradiated in utero thus seem to possess less labile nervous systems. This reters above all to the inhibitory process, which explains the pathological lability of the excitatory process. (OTS)

• Research Organization: Inst. of Higher Nervous Activity and Neurophysiology, Moscow
• NSA Number: NSA-17-030454
• OSTI ID: 4704417
• Journal Information: Zh. Vysshei Nervnoi Deyatel'nosti im. I.P. Pavlova, Journal Name: Zh. Vysshei Nervnoi Deyatel'nosti im. I.P. Pavlova Vol. Vol: 12
• Country of Publication: Country unknown/Code not available
• Language: English

Related Subjects

AGE
BEHAVIOR
BIOLOGY AND MEDICINE
BODY
CONDITIONED REFLEXES
DOGS
FOOD
GLANDS
GONADS
NERVOUS SYSTEM
PHYSIOLOGY
PREGNANCY
RADIATION DOSES
RADIATION EFFECTS
SEX
SURGERY
TESTING
VARIATIONS