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T V Aleĭnikova

Publications and source records attributed to T V Aleĭnikova.

At least 19 recordsLinked to original sources
PubMed1984

[Responses and organization of the receptive fields of neurons of the basal optic nucleus of the frog tegmentum during visual stimulation].

Stationary visual stimuli and diffuse light induced mainly excitatory responses of the neurons. Among the neurons responding to visual stimulations many units were the polysensory cells responding also to tactile and sound stimuli. The questions of organization of the tegmental neurons' visual receptive fields, are discussed. Prevalence of large receptive fields has been noted, mainly excitatory those or having an excitatory center and inhibitory periphery.

Animals↗
PubMed1983

[Morpho-functional organization of the optic thalamic system in the frog].

Histological and electrophysiological studied of the frog thalamus localized more precisely the Bellonci and the posteriorthalamic nuclei in the diencephalon. Responses of the thalamic neurons have been characterized as well as the specifics of their receptive fields as compared with the tectum neurons. Large heterogeneous receptive fields with prevailing excitatory response were shown to predominate in the frog diencephalon.

Animals↗
PubMed1983

[Space-time organization of neuronal activity in the frog tectum and its transformation in response to different visual stimuli].

The space and time organization of neuronal activity was studied in the frog tectum opticum under the action of different visual stimuli. It is shown that inhibition plays an important role in neuronal reactions. It is suggested that differences in the space time parameters of neuronal activity reflect differences in visual signals which bring optic information from the retina.

Animals↗
PubMed1983

[Reactions of the tectum neurons of the frog to movement into its field of vision of an object with different velocities].

Neurons with different "velocity selectiveness" and different "velocity sensitivity" were found in the frog midbrain tectum as well as neurons with different types of the firing rate dependence on the velocity of a visual stimulus motion. Visual recognition in frogs seems to proceed with the aid of two systems: the image--detecting and the image--describing those which complement each other.

Animals↗
PubMed1982

[Neuronal level of visual analysis organization in the frog tectum].

Using coupled microelectrode studies of the frog tectum neuronal responses to diffuse light or moving visual stimulus, the excitatory-inhibitory constructions were revealed in the midbrain tectum. The size of excitatory areas of these constructions is about 100-200 mu with intevening inhibitory areas. It proved possible to find a correlation between the size of the excitatory tectal constructions appearing in different types of visual stimulation and the width of the branching areas as well as the site of terminals of the visual afferents and intratectal fibers.

Animals↗
PubMed1982

[Visual information coding in the frog midbrain tectum].

Possible mechanisms of optic information encoding in the frog tectum are considered on the basis of the extracellular recording of the tectum neuron impulse activity. It is suggested that optic information is coded in the frog tectum by means of space coding and is made more precise with the help of different types of time-coding, the coding by latency difference being used more widely. This mechanism may function either independently or be a component of complex time-codings. A uniform distribution in the tectal structures of neurons processing optic information indicates that the mechanism of exact analysis of optic stimulus movement parameters should be a distribution function of the same structures.

Animals↗
PubMed1981

[Distribution of direction-rate of movement neurons in frog optic tectum structures].

The neurons related to movement direction--velocity are equally distributed in the tectum opticum layers with representation in the latters of sensory, associative and effector structures which suggests equal participation of these structures in estimation of parameters of the visual stimulus movement. In the tectum opticum neurons, the inhibition restricting the excitation, seems to facilitate responses of separate groups of neurons related to analysis of direction--velocity parameters.

Animals↗
PubMed1976

[Responses of directionally sensitive neurons of the frog midbrain tectum, their adaptation and extrapolation responses].

The greatest coherence of responses and latency for neuronal pairs was found at interelectrode distances up to 300 microns which is due, apparently, to dimensions of the afferent fibers' branching areas. The adaptation and extrapolation features observed in majority of the neurons, were more obvious in the tectum nuclear layers rather than in the fiber those. The more stable responses of the fiber layers' neurons suggest a representation of branches stemming from the fibers of the retina ganglionic cells, while in the nuclear layers the elements with high adaptability: the "novelty neurons", are localized.

Adaptation, Physiological↗