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Biomedical subjects

M A Kulikov

Publications and source records attributed to M A Kulikov.

At least 19 recordsLinked to original sources
PubMed2006

Recovery of a motor skill in rats with different forelimb preferences after lesioning of the caudate nucleus: the role of intense training.

The aim of the present work was to study the effects of training on the restoration of a lateralized motor skill (a food-procuring forelimb movement) in Wistar rats (n = 83) after lesioning of the caudate nucleus in conditions of infrequent testing and intensive retraining. On the basis of the training results, the rats were divided into those preferring the right (right-handers) or left (left-handers) limb. Testing was followed by lesioning of the head of the caudate nucleus on the side contralateral to the preferred paw. Animals with identical initial preferences were then divided into two groups: an infrequently tested group in which recovery of the skill was tested once weekly for five months, and an intensive retraining group, in which experiments were performed 3-4 times weekly, again for five months. After surgery, animals had to perform the food-procuring skill only with the "impaired" paw. Differences in the recovery of the skill were seen in animals with different limb preferences both in conditions of spontaneous recovery and in those recovering with training. Overall, animals with lesions of the left caudate nucleus (right-handers) showed better recovery than animals with lesions of the right caudate nucleus (left-handers) in both spontaneous recovery and in recovery with training. These findings suggest that the central neural mechanisms of recovery of a lateralized motor skill after unilateral lesioning of the caudate nucleus are different after lesions to the right and left hemispheres.

Animals↗
PubMed2005

Behavioral characteristics of WAG/Rij rats susceptible and non-susceptible to audiogenic seizures.

Some rats of the WAG/Rij (Wistar Albino Glaxo from Rijswijk) and Wistar strain are susceptible for audiogenic (convulsive) seizures. In the present study, behavior of susceptible and non-susceptible rats from the WAG/Rij strain, genetically predisposed to absence epilepsy, and outbred Wistar strain, genetically not predisposed to absence epilepsy, was compared to assess the level of anxiety (in the open field, light-dark choice and elevated plus-maze tests) and the level of depression (in the sucrose consumption and forced swimming tests). Increased level of anxiety was found only in audiogenic susceptible rats both from WAG/Rij and Wistar strain, but increased level of depression was found only in WAG/Rij rats independently of their susceptibility to audiogenic seizures. The results suggest that enhanced level of depression in WAG/Rij strain rats is associated with absence epilepsy but enhanced level of anxiety with susceptibility to audiogenic seizures.

Analysis of Variance↗
PubMed2005

Supervised learning of postural tasks in patients with poststroke hemiparesis, Parkinson's disease or cerebellar ataxia.

Supervised learning of different postural tasks in patients with lesions of the motor cortex or pyramidal system (poststroke hemiparesis: 20 patients), nigro-striatal system (Parkinson's disease: 33 patients) and cerebellum (spinocerebellar ataxia: 37 patients) was studied. A control group consisted of 13 healthy subjects. The subjects stood on a force platform and were trained to change the position of the center of pressure (CP) presented as a cursor on a monitor screen in front of the patient. Subjects were instructed to align the CP with the target and then move the target by shifting the CP in the indicated direction. Two different tasks were used. In "Balls", the target (a ball) position varied randomly, so the subject learned a general strategy of voluntary CP control. In "Bricks", the subject had to always move the target in a single direction (downward) from the top to the bottom of the screen, so that a precise postural coordination had to be learned. The training consisted of 10 sessions for each task. The number of correctly performed trials for a session (2 min for each task) was scored. The voluntary control of the CP position was initially impaired in all groups of patients in both tasks. In "Balls", there were no differences between the groups of the patients on the first day. The learning course was somewhat better in hemiparetic patients than in the other groups. In "Bricks", the initial deficit was greater in the groups of parkinsonian and cerebellar patients than in hemiparetic patients. However, learning was more efficient in parkinsonian than in hemiparetic and cerebellar patients. After 10 days of training, the hemiparetic and cerebellar patients completed the acquisition at a certain level whereas the parkinsonian patients showed the ability for further improvement. The results suggest that motor cortex, cerebellum, and basal ganglia are involved in voluntary control of posture and learning different postural tasks. However, these structures play different roles in postural control and learning: basal ganglia are mainly involved in learning a general strategy of CP control while the function of the motor cortex chiefly concerns learning a specific CP trajectory. The cerebellum is involved in both kinds of learning.

Adult↗
PubMed2004

Characteristics of learning voluntary control of posture in lesions of the pyramidal and nigrostriatal systems.

The aim of the study reported here was to investigate impairments on the learning of voluntary control of the center of pressures using visual feedback in patients with lesions of the corticospinal and nigrostriatal systems. Participants were 33 patients with Parkinson's disease and 20 patients with hemipareses due to circulatory lesions in the basin of the middle cerebral artery. Subjects stood on a stabilometric platform and used two computer games over 10 days to learn to shift the body relative to the foot to move the centre of pressures, indicated by the position of a cursor on the screen, with the target and to move the target to a specified part of the screen. The games differed in terms of the postural tasks. In one, the direction of movement of the center of pressures was not known to the subjects, and subjects learned a general strategy for posture control; the other formed a strictly defined postural coordination. Both groups of patients were found to have impairments of voluntary control of the position of the center of pressures. There were no differences between groups of patients, in terms of the severity of the initial performance deficit in the task involving shifts of the center of pressures in different directions (the general strategy for controlling the center of pressures), while learning of this task was more difficult for patients with Parkinson's disease. The initial deficit in the fine postural coordination task was more marked in patients with Parkinsonism, though learning in these patients was significantly better than in patients with hemipareses. It is suggested that the mechanisms of involvement of the nigrostriatal and corticospinal systems in learning the voluntary control of posture have elements in common as well as unique elements.

Adult↗
PubMed2004

[Voluntary postural control learning with a use of visual bio-feedback in patients with spinocerebellar degenerations].

The study aimed at evaluation of possibility and features of voluntary postural control learning using biofeedback from a force platform in patients with spinocerebellar ataxias. Thirty-seven patients with different forms of spinocerebellar degenerations and 13 age-matched healthy subjects were trained to shift the center of pressure (CP) during several stabilographic computer games which tested an ability to learn 2 different types of voluntary postural control: general strategy and precise coordination of CP shifting. Despite the disturbances of static posture and ability for voluntary control of CP position, patients with spinocerebellar degenerations can learn to control a vertical posture using biofeedback on stabilogram. In contrast to healthy subjects, improvement of coordination in the training process does not exert a significant influence on the static posture characteristics, in particular on lateral CP oscillations. The results obtained suggest involvement of the cerebellum in both types of postural control that distinguishes them from pathology caused by motor cortex and nigro-striatal system involved only in one type of postural control.

Adolescent↗
PubMed2003

Depressive-like behavioral alterations and c-fos expression in the dopaminergic brain regions in WAG/Rij rats with genetic absence epilepsy.

Wistar derived inbred line, the WAG/Rij rats, genetically absence epilepsy prone and their normal counterparts, outbred Wistar rats, were compared in respect to differences in behavior, in acute and chronic antidepressant imipramine treatment and in the immediate early gene c-fos expression in the brain regions induced by forced swimming test procedure. The WAG/Rij rats as compared with Wistar rats were found to exhibit decreased activity in the open field test, increased immobility in the forced swimming test and decreased sucrose intake (anhedonia). Interline differences indicating increased anxiety in the WAG/Rij rats were not revealed in the light-dark choice, social interaction and elevated plus-maze tests. The WAG/Rij rats in contrast to Wistar rats responded only to chronic antidepressant imipramine treatment with a reduction in their enhanced immobility in the forced swimming test. "Behavioral despair" induced by forced swimming led to c-fos expression in frontal cortex, nucleus accumbens and striatum, terminal regions of three dopaminergic brain systems (mesocortical, mesolimbic, nigrostriatal). The c-fos expression in the brain of WAG/Rij rats was substantially higher than that of Wistar rats. Moreover, the strains differed in the distribution of c-fos expression between brain regions. Results suggest that WAG/Rij rats are prone to adopt passive strategies of behavior in stressful situations, and so in this certain aspect this strain might be regarded as new experimental (genetic) model of depressive-like (passive) behavior accompanying absence epilepsy. Further testing this hypothesis is proceeding. This putative model could be used for the investigation of neurobiological basis and mechanisms of such "double pathology" and for the examination of new concepts of its therapy.

Animals↗
PubMed2003

Spatial distribution of coefficients of asymmetry of brain bioelectrical activity during the experiencing of negative emotions.

Significant differences in the spatial distribution of the coefficients of asymmetry of the power of bioelectrical activity were identified in negative emotions of different qualities (anger and grief). In the case of the sthenic (excitable) emotion anger, there was an increase over baseline in the positive value of the coefficient of asymmetry in the anterior areas and the beta2 range, while for the asthenic emotion grief, there was an increase in the negative value of the coefficient in the beta1 range and a generalized increase in slow-wave activity.

Adult↗
PubMed2002

[The spatial distribution of asymmetry coefficients of the brain bioelectric activity while experiencing negative emotions].

Statistically significant differences were revealed in the spatial distribution of the asymmetry coefficients in the brain bioelectrical activity for different negative emotions. In case of the asthenic emotion (anger) the asymmetry coefficients in the beta-2 band were positive and greater in the frontal part of the brain as compared to the background. When the subjects experienced (imagined) the asthenic emotion (grief), the asymmetry coefficients were negative in the beta-1 band and a generalized growth of slow-wave activity was observed.

Adult↗
PubMed2001

[EEG peculiarities in posttraumatic Korsakov's syndrome].

The paper presents an attempt to define the structures of the cerebral functional pathologic system in the Korsakov's syndrome (KS) that develops after a severe craniocerebral trauma. 32 patients with reversible (21) and irreversible (11) KS variations were examined. Visual and coherent EEG-analysis was performed as well as determination of the three-dimensional location of the equivalent dipole sources of the separate pathologic components of the bioelectric activity. The data obtained were compared with the clinical ones. The role of both diencephalic and subcortical (including hippocampus) structures in KS development as well as the role of the right hemisphere were confirmed. Significance of the anterior (temporal-frontal-central) regions of the right hemisphere in KS regression was found. The degree of the injury of nonspecific frontal and brain stem structures and involvement of the left hemisphere into the pathological process together with the right one is essential for KS reversibility.

Adolescent↗
PubMed2000

[Prophylactic effect of antioxidant Aekol on behavioral (psychoemotional) disturbances caused by chronic stress in rats].

Antioxidant preparation "Aekol" containing vitamins A, E, and K3, was shown to possess antidepressant properties and to exert a prophylactic effect on behavioural (psychoemotional) disturbances induced by a chronic stress in rats: a depressive condition associated with an enhanced anxiety, elimination of individual differences in behaviour, weakening of the relationships among behavioural parameters recorded in the same animal in three different tests.

Animals↗
PubMed1996

Coordination between posture and movement in a bimanual load-lifting task: is there a transfer?

The present experimental series was designed to test the possibility that an anticipatory postural adjustment learned during the performance of a bimanual load lifting task may be transferred between the upper extremities. Eight seated subjects were asked to maintain horizontally one forearm (postural arm) loaded with a 1-kg load, which was fixed to the arm by means of an electromagnet. The unloading was triggered either by the experimenter pressing a switch (control) or by the subjects making a voluntary movement with their other arm (moving arm). In the latter case, the subject lifted a 1-kg load resting on a force platform with the moving hand, and the switching off was triggered when the force level reached a threshold of 0.5 kg. The maximum amplitude (MA) and the maximum velocity (MV) of the postural forearm elbow joint rotation occurring after the unloading were measured at each trial. The learning process was estimated by performing a regression analysis on each series of trials, using an exponential model, and from the intercept of the regression curve with the ordinate. 1. During the original learning session (three series of 20 trials), a decrease in MA and MV was found to occur both within the series and between the series during a session. 2. After the initial learning session, the sides of the postural and moving arm were interchanged to test whether any transfer had occurred. The first series of trials in the second session (transfer) and the last series of trials in the original learning session were compared and found to be significantly different in terms of the intercept (seven subjects in the case of MA, five subjects in the case of MV) and the slope (five subjects), indicating a lack of transfer. 3. The data recorded during the second transfer learning session indicated that learning occurred in all eight subjects in the case of MA and in six subjects in the case of MV. It was observed that the original learning session did not facilitate the second one. 4. The lack of transfer of the anticipatory postural adjustment observed in this task is discussed with reference to the data in the literature.

Conditioning, Psychological↗
PubMed1993

Differences in the recovery rate of a learned forelimb movement after ablation of the motor cortex in right and left hemisphere in white rats.

After ablation of the motor cortex contralateral to the preferred limb, rats were forced to use this limb in grasping food out of a horizontal tube by restraining the non-preferred foreleg with a bracelet. In a right-handed rat the motor behaviour is less impaired and the recovery is better after a left hemisphere lesion in comparison with a left-handed rat after a right hemisphere lesion. This difference is primarily the time needed to use the limb in reaching for seed (testperiod 3) and the total time needed for 10 successive seizings of seed (testperiod 5). Surprisingly, the differences in the course of recovery do not correlate with the degree of preoperative limb preference: the initially ambidextrous rate also show the same differences in results of the motor cortex ablation in left and right hemisphere. However, in the group of initially consistent ambidextrous rats, after 10 weeks of tests with a restrained forelimb, the testing under unrestrained free conditions shows a gradual decrease in the induced limb preference and a shift to the use of the foreleg contralateral to the intact hemisphere, while in contrast the initially consistent left- or right-handed rats preserve the limb preference under the unrestrained testing conditions. Therefore the degree of initial preference still influences the choice of limb after motor cortex ablation and intensive training to use the 'damaged' limb.

Animals↗
PubMed1993

[Effect of substance P on survival of rats after cerebral ischemia: the effect depends on behavior type].

In rats with different behaviour types in tests of "open field" and "forced swimming", influence of intraperitoneal administration of P-substance (PC) neuropeptide to survival and structural-metabolic changes in brain after double-sided ligating of carotid arteries. It was established that PC exerts different influence on stability to circulating cerebral hypoxia according to behaviour types: it increases stability in rats with passive behaviour type, decrease stability in rats with active behaviour type and does not influence on rats with middle behaviour type. Results shows the necessity of individual approach to peptide use with the view to increase stabilization to cerebral ischemia.

Animals↗
PubMed1991

Innate versus learned factors determining limb preference in the rat.

The basic factors determining forelimb preference in the performance of different skilled movements were studied in white rats. To analyse whether limb preference actually reflects an initial individual motor asymmetry or is a result of instrumental learning (the first successful movement becoming fixed), the method of retrograde amnesia from electroconvulsive shock was used. It was shown that limb preference is initial and not a results of learning and, evidently, is due to intrinsic factors. The preferred limb can be identified in as few as 3 successful movements. There is a gradation among animals according to the degree of initial limb preference and its resistance to rearrangement of the motor task. The differences of limb preference in different movements were also analysed. Dependence of the preference on the character of the required movement was shown. Four basic types of movement were revealed by factor analysis. As different muscular groups (distal and proximal), controlled by different descending motor systems can be involved in the performance of different movements, it is assumed that the initial motor asymmetry in each movement is a result of asymmetry of central motor structures involved in the realization of the movement. In the same animal asymmetry of different motor structures might be different. This could explain different limb preference in different movements.

Animals↗