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An analysis was made of the dynamics of probabilistic characteristics of the rat behaviour in the process of extinction of orienting-investigating behaviour in the "open field". Estimation of the entropy value related to behaviour permitted to divide the rats into two groups. The rats with high entropy values differed from those with low values by a more prolonged retention of a high level of locomotion, vertical stands, wall stands, peeping through a hole and grooming. It is suggested that a high entropy level and prolonged retention in the behaviour pattern of most of the elementary acts and poses may testify to a delayed process of extinction of orienting-investigating activity due to a higher level of the rats negative emotional state.

The role of the pituitary in the mechanisms of posttraumatic reorganizations of the segmental apparatus was studied. Hypophysectomized rats failed to demonstrate postural asymmetry after spinal cord hemisection. The lack of asymmetry is connected with a considerable decrease in postural asymmetry factor activity in the cerebrospinal fluid and cerebral tissue. It was established that pituitary tissue is characterized by the maximal level of postural asymmetry factor activity after hemisection.

Conventional approaches to the treatment of stammering were judged ineffective in terms of both the percentage of patients cured and the relapses rate. Application of the new devices, e.g., biofeedback ones, combined with the conventional techniques only fairly improved the situation. A new combined technique is offered. It derives from a neurophysiological approach allowing one to destabilize the pathological speech pattern and create prerequisites for a quick learning (10 to 20 days) of the logopedical skills. The technique proved highly effective both in adults and in pre-school children. It was used to cure more than 500 patients with 1.5 to 7 years follow-up.

A hypothesis of informational switching of conditioned activity is proposed on the basis of experimental data, demonstrating coding of nervous processes in distribution of uncrossed classes of neuronal interpulses intervals (IPI) and functional interaction between neurones selective to IPI. According to the hypothesis, informational switching represents the ability of nervous chains to change the channels of efferent output in response to one and the same afferent signal, depending on impulse intervals characteristics of control signal, created inside the CNS or coming from without. Schemes are given of informational switching and their description in connection with CRs switching over.

On snails, the action was studied of hemolymph of donors with conditioned food refusal reflex on acquisition of the same habit by intact snails-recipients in case of coincidence or of difference of conditioned stimuli in donors and recipients. Specific component of the facilitating effect was distinctly manifest at selection of optimal doze of hemolymph and depended on the season. At non-optimal parameters of the experiment the specific component of the facilitating effect was masked by the non-specific one, or an inhibitory effect took place. The data obtained testify to multicomponent composition of the neurohumoral link in the mechanism of conditioned reflex formation.

In analysis of neuronal activity of g. proreus of dogs brain in response to positive and differentiation conditioned cutaneous stimuli, in 44% of 78 studied neurons "late responses" appeared in the form of impulse activity intensification elicited by a positive conditioned stimulus after the end of eating and by a differentiation one--during conditioned signal action; it persisted in different neurones for 30--60 s. By means of various functional tests it has been shown that these reactions are a neurophysiological correlate of animals emotional state gradient.

Structural characteristics (survival, growth, connections) have been studied in the transplant of the cerebral cortex tissue in Wistar rat embryos (18-day-old), implanted into the brain of mature rats of the same line at various time after a partial lesion of the sensomotor cortex. In 3-5 months after transplantation the light microscopy methods demonstrate that spatial interconnections of the transplant and the injured brain of the recipient depend on time interval between the cerebral lesion and transplantation of the embryonal nervous tissue. Horseradish peroxidase (HP) is ionophoretically injected into the recipient's cerebral tissue away from the place of transplantation. In the transplant retrogradely labelled HP neurons are revealed. This demonstrates efferent connections of the implanted tissue with the host's brain. Presence of the anterogradely labelled nervous terminals in the transplant tissue demonstrates existence of afferent connections of the transplant with the recipient's tissue. Possible mechanisms of survival, growth and formation of connections of the transplant in the injured brain of the mature animal are discussed.

The distribution of the low-molecular weight and high-molecular weight postural asymmetry factors (FPA) activity in the left and right parts of the lumbal region of the rat spinal cord was studied. Low-molecular weight FPA induces flexion of the hind limb ipsilateral to the half of the spinal cord from which FPA was isolated, while high-molecular weight FPA induces contralateral flexion. The activities of the low- and high-molecular weight FPAs in each half of the spinal cord are comparable in normal rat. After the suction lesion of the motor areas in the left hemisphere the increase of the low-molecular weight FPA activity in the right half of the lumbal region of the spinal cord was observed.

The chemical factors of the postural asymmetry (FPA) were studied on the recipients without hemispheres. The structural specificity of the fore and hind limb spinal centers regulation in normal and damaged CNS was observed. In the normal CNS this structural specificity was displayed in the selective activation of the cross-situated hemicenters in the cervical and lumbal regions (for example in the left part of the cervical and in the right part of the lumbal region). In the case of the unilateral lesion of the central motor systems the normal pattern of chemical structural specificity was modified by activation of FPA selectively acting on the partly denervated regions of the spinal cord.

Emotiogenic (reinforcing) abilities of the hypothalamic lateral nucleus and cortico-medial part of the amygdala were studied with locomotor and lever self-stimulation techniques in normal rats and in those which had been kept under partial sensory and intraspecies deprivation during early postnatal development. A noticeable increase in size and excitability of negative reinforcing areas occurred in the latter rats. The data obtained suggest that limitation of early individual experience results in including of polyfunctional emotiogenic structures into the systems of negative emotion regulation.

The role of neurohumoral factors in the mechanisms of restoring the lost motor functions after two successive unilateral removals of the neocortex motor region, was studied. The dynamics of the restoring correlated with the posture asymmetry factor (PAF) activity in the CSF. PAF activity was reduced during the restoring by an inactivation factor (FI). Periods of restoration after the 2nd extirpation and inactivation of PAF were shorter than after the 1st one. The existence of the FI before the 2nd extirpation may account for this phenomenon.

A peptide factor, responsible for a phenomenon of posture asymmetry and characterized by a high selectivity of action, was isolated from rat brain. Studies on the amino acid sequence in the peptide are carried out.

The authors studied the time-course of functional rearrangements of the segmental apparatus after unilateral injury of the rat motor cortex. It was found that one day after injury the postural asymmetry of the hind limbs was fixed by the lumbal region of the spinal cord. This functional state of the segmental apparatus lasted 10 days after injury in the presence of the maximal activity of postural asymmetry factor (PAF) in the CSF and increasing activity of the factor in the brain tissue. Recovery of the segmental apparatus to symmetrical function by the end of the third week following injury was accompanied by PAF inactivation.