Neirofiziologiia = Neurophysiology最新文献

{"title":"[Double orientation tuning of neurons of the primary visual cortex of the cat at various levels of alertness].","authors":"N A Lazareva,&nbsp;I A Shevelev,&nbsp;R V Novikova,&nbsp;A S Tikhomirov,&nbsp;G A Sharaev","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>Orientation tuning (OT) of 225 visual cortex neurons was studied in immobilized cats by their responses to flashing light bars. It was found that 43% of neurons had monomodal OT and preferred the horizontal and vertical orientations, while 57% of neurons had double OT, i.e. they had main preferred orientation (PO) and additional PO (aPO). The mean angle between PO and aPO was equal to 71.4 +/- 2.4 degrees. In half of the cases the second maximum of OT was equal to the first one (mean: 0.7 +/- 0.03 from PO). Orientation characteristics of PO and aPO were practically identical. Under light and middle levels of narcosis half of the neurons with double OT became monomodal and 12% of monomodal neurons receive bimodal OT. Monomodal neurons had more often simple RF and invariance of OT to narcosis. The neurons with double OT had simple and complex RF equally often and their OT changed in narcosis. It is supposed that the neurons with double OT can be an angle and line cross detectors. Monomodal neurons may be the stable bench mark system of orientation coordinates. Interaction of these neuronal systems permits conducting an effective analysis of image features in the primary visual cortex.</p>","PeriodicalId":19121,"journal":{"name":"Neirofiziologiia = Neurophysiology","volume":"24 3","pages":"260-9"},"PeriodicalIF":0.0,"publicationDate":"1992-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"12682505","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"[Switching effect in the system of equilibrium regulation in man].","authors":"V S Gurfinkel',&nbsp;M A Lebedev,&nbsp;Iu S Levik","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>Postural reactions evoked in human by bilateral vibration of calf muscles were studied under different conditions: sitting without the feet contact with a support; sitting in an unstable position on the edge of the chair; sitting under conditions of the foot contact with different types of supports (rotating disk, suspended platform, etc.); standing with an asymmetrical load applied to the trunk. It has been shown that local vibration of calf muscles can evoke activation not only of the vibrated muscle or of its antagonist (local effects), but also of extensors and flexors of the knee joint (non-local effects), or of the remote muscular groups, involved in different postural synergies. The concrete pattern of muscle activation is determined by several factors, the most important being the relative position of the body links and interaction of feet with a support. The mental image of the body configuration in the system of internal representation is also very significant.</p>","PeriodicalId":19121,"journal":{"name":"Neirofiziologiia = Neurophysiology","volume":"24 4","pages":"462-70"},"PeriodicalIF":0.0,"publicationDate":"1992-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"12606758","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"[The generator of locomotor activity as the probable modulator of the afferent flow from the thermoreceptors of the skin fields of the flexor and extensor muscles].","authors":"M B Abuziarov,&nbsp;A V Chemeris,&nbsp;G Kh Abeuova,&nbsp;S A Ibragimova","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>The excitability of flexors and extensors of the upper and low extremities was studied in healthy people and in patients with spasticity during local thermostimulation of their receptive fields using H-reflex (HR). In healthy people the HR was inhibited during cooling and was enhanced during warming. Thermostimulation of the contralateral side caused a contraverse reaction. In patients cooling of skin followed the rise of HR. The obtained data show that the condition of the thermoreceptive fields can influence reflex excitability of motoneurons. The character of this influence depends on the initial condition of the locomotor generator.</p>","PeriodicalId":19121,"journal":{"name":"Neirofiziologiia = Neurophysiology","volume":"24 5","pages":"598-604; discussion 633-5"},"PeriodicalIF":0.0,"publicationDate":"1992-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"12606600","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"[Hysteretic properties of movements in the elbow joint of unanesthetized cats with various methods of activation of muscle-antagonists].","authors":"A N Tal'nov,&nbsp;A I Kostiukov","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>Movements of the elbow joint were studied in unanesthetized cats. These movements were evoked by microstimulation of the motor cortex or by vibration of the forepaw and then compared with reaction from direct stimulation of muscles in the anesthetized animals. Interaction of the hysteretic effects in the antagonistic muscles of the joint was studied during stimulation of two points of the motor cortex which produced opposite-directed movements. Coactivation of the antagonists was shown to increase both the joint stiffness and the uncertainty of the equilibrium value of the joint angle. The uncertainty myotatic reflexes during intracortical microstimulation were more significantly depressed in the muscle receiving more intensive activation from the given point in the motor cortex. On the contrary, myotatic reflexes during vibration were well expressed in the both antagonistic muscles. At the same time the uncertainty effects during forepaw vibration were displayed similarly as it was in the cortically evoked movements.</p>","PeriodicalId":19121,"journal":{"name":"Neirofiziologiia = Neurophysiology","volume":"24 3","pages":"322-30"},"PeriodicalIF":0.0,"publicationDate":"1992-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"12682326","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"[Inhibition of neuronal responses in the cat motor cortex, associated with attainment of a conditioned reflex when waiting for a flash of light].","authors":"B I Busel',&nbsp;A P Kniga","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>Inhibition of neuronal spike reactions associated with reflex movements and induced by the light flare at different moments during the conditioned stimulation (1 s.) has been found in chronic experiments on cats. The light flare in the interval of maximum probability of the reflex realization has promoted a rise in the neuronal latency by 300-400 ms and a decrease of their duration almost twice. Other realizations of the inhibition effect were weaker.</p>","PeriodicalId":19121,"journal":{"name":"Neirofiziologiia = Neurophysiology","volume":"24 3","pages":"340-3"},"PeriodicalIF":0.0,"publicationDate":"1992-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"12682328","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"[Effect of magnesium ions on the functional state of postsynaptic membrane by modulation of the level of non-quantal secretion of the mediator].","authors":"R N Khazipov,&nbsp;R A Giniatullin","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>The role of non-quantal secretion (NS) of acetylcholine (ACh) in shortening of miniature end-plate currents (MEPC) after initial prolongation of MEPC due to acetylcholinesterase (AChE) inhibition was studied in the mouse diaphragm muscle under the voltage clamp conditions. Elevation of NS level by removal of magnesium ions from solution accelerated the shortening effect. After elimination of NS due to an increase of magnesium concentration up to 3 mmol/l the shortening of MEPC was absent. It was suggested that after AChE inhibition the magnesium ions in physiological range of concentrations can modulate the desensitization development on postsynaptic membranes by NS level regulation.</p>","PeriodicalId":19121,"journal":{"name":"Neirofiziologiia = Neurophysiology","volume":"24 1","pages":"97-100"},"PeriodicalIF":0.0,"publicationDate":"1992-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"12751243","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"[Rearrangements of efferent activity parameters in generators of cyclic motor reactions during electric stimulation of cerebellum inputs and outputs in the cat].","authors":"A M Degtiarenko","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>Rearrangements of the activity parameters of scratching and locomotor generators conditioned by electric stimulation of the inferior olive, nucleus reticularis lateralis as well as of the fastigial nucleus and nucleus interpositus of the cerebellum were investigated on decerebrate immobilized animals. Scratching and locomotor generators were characterized by the ability to effectively rearrange the time structure of their activity in response to certain changes in phase and amplitude characteristics of signals arriving both by the mossy and climbing inputs of the cerebellum. The flexor half-centre of the locomotor generator and aiming half-centre of the scratching generator increased both the period and intensity of their activity under influence of signals arriving to the cerebellum from the inferior olive and nucleus reticularis lateralis at the first half of the working phase of these half-centres. Stimulation of the inferior olive and nucleus reticularis lateralis during the second half of the flexor and aiming phases evoked somewhat different changes in correlation of activity for half-centres of the locomotor and scratching generators. A slight shortening of the activity period of the aiming half-centre during scratching and a decrease of the activity period of the extensor half-centre during locomotion were observed. Stimulation of the structures mentioned above during the working phase of half-centres controlling limb extensor movements evoked shortening of the extensor half-centres activity period during locomotion and exerted no effect on the scratching jerk half-centre activity period during scratching. The scratching generator, unlike the locomotor generator is characterized by a significant degree of resemblance of the rearrangement of generator efferent activity parameters evoked by electric stimulation of the cerebellum nuclei and its afferent inputs. Possible mechanisms of forming the correcting influences on scratching and locomotor generators from the cerebellum during changes in phase and amplitude characteristics of its input signals are discussed.</p>","PeriodicalId":19121,"journal":{"name":"Neirofiziologiia = Neurophysiology","volume":"24 2","pages":"131-40"},"PeriodicalIF":0.0,"publicationDate":"1992-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"12765131","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"[Repetitive firing in motor nerve endings: modulation by divalent cations, rhythmic activation and cholinergic agents].","authors":"R A Giniatullin","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>The phenomenon of repetitive firing (RG) in motor nerve endings induced by 4-aminopyridine (4-AP) was studied in cut sartorius frog muscle under the voltage clamp conditions. In the presence of 4-AP (1.10(-4) mol/l) one stimulus applied to the nerve induced two end plate currents (EPC) in half of cells studied (n = 35). The elevation of calcium ion concentration up to 5.4 mmol/l or magnesium to 5-9 mmol/l or rhythmic activity (0.05 Hz and above) abolished RF. Substitution of calcium by strontium or barium enhanced RF (the number of EPC during the burst of RF). EPC with very slow time course were observed in some cells in the presence of barium, that disrupted to the burst of RF by repetitive nerve stimulation. Neostigmine, an anticholinesterase agent, increased the number of EPC in the burst of RF, but alpha-bungarotoxin exerted no effect on the RF. The role of calcium and calcium-activated potassium currents in generation and termination of RF in motor nerve endings is discussed.</p>","PeriodicalId":19121,"journal":{"name":"Neirofiziologiia = Neurophysiology","volume":"24 4","pages":"387-95"},"PeriodicalIF":0.0,"publicationDate":"1992-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"12607010","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"[Effect of trans-ACPD, a specific agonist of glutamate interacting with metabotropic receptors, on synaptic transmission in the rat hippocampus].","authors":"O V Garashchuk,&nbsp;Iu N Koval'chuk,&nbsp;O A Kryshtal'","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>Trans-ACPD, a cyclic analogue of glutamate, has been studied for its influence on field potentials and excitatory postsynaptic currents (EPSCs) in the CA1 layer. Being applied in concentration 50 microM and above, trans-ACPD completely and reversibly inhibited excitatory postsynaptic field potentials but has no effect on EPSCs. Trans-ACPD in the same concentration reversibly reduced the amplitude of antidromic population spike in the CA1 layer, but has an insignificant effect on antidromic population spike in the CA3 layer.</p>","PeriodicalId":19121,"journal":{"name":"Neirofiziologiia = Neurophysiology","volume":"24 2","pages":"211-4"},"PeriodicalIF":0.0,"publicationDate":"1992-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"12523185","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"[Neurophysiologic changes and bound calcium dynamics during the elaboration of associative learning in Helix lucorum].","authors":"V P Nikitin,&nbsp;S A Kozyrev,&nbsp;M O Samoĭlov","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>Neurophysiological effects and dynamics of bound calcium (Ca-b) in command neurons of defense behavior (LP11 and RP11) during food aversion conditioning were studied in snail Helix lucorum. It was found that during associative learning both conditioned reaction and nonspecific facilitation of sensory responses were determined in neurons. The nonspecific facilitation of sensory responses was similar to that found during sensitization development in neurons. However, conditioned response appeared 30 min later than long-term sensitization development. Specific dynamics of the Ca-b level in neurons was obtained after three and more conditioning. The dynamics of the Ca-b level correlated with neurophysiological effects and differed from those measured during sensitization development. It is suggested that molecular mechanisms underlying associative learning and sensitization are different in a command neuron of defense behavior in the snail.</p>","PeriodicalId":19121,"journal":{"name":"Neirofiziologiia = Neurophysiology","volume":"24 6","pages":"691-701"},"PeriodicalIF":0.0,"publicationDate":"1992-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"12663974","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}