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E F Semeniuk

Publications and source records attributed to E F Semeniuk.

3 recordsLinked to original sources
PubMed1983

[Responses of neurons in the sensomotor cortex of the cat to auditory stimuli of different duration before and after elaboration of a conditioned reflex].

Evoked activity of cells in the sensomotor cortex to sounds of various duration (0.001, 0.1, 1 s) before and after conditioning was studied in experiments with cats. The highest percentage of evoked responses, intensity and duration of neuronal reactions were observed during the long sound stimulation (1 s). A conclusion is made that the long sound was most effective for conditioning.

Animals↗
PubMed1978

[Dynamics of neuronal reactions during elaboration of a conditioned defensive reflex to sound].

When elaborating and realizing defensive conditioned reflexes in cat cortex areas 3 and 4 series of phases was distinguished in the neuronal reactions: initial response, short-lasting depression of activity, early and late after-discharges, activation after sound cessation. The initial response arose or was augmented during the beginning of the reflex elaboration (initial 5-15 stimuli combinations). After-discharges were relatively stabilized to the 20th-40th combinations. Conditioned motor reactions occurred 100-400 ms after the onset of the sound. Movements usually coincided with early after-discharges of cortical neurons during both real conditioned reflexes and initial period of trace reflexes. Differential neuronal reactions were elaborated with the same efficacy as positive ones. The conditoional stimulus reinforcement plays an important role not only in increasing neuronal excitability (which is significant for acquiring polysensory properties), but also in modifying after-discharges.

Animals↗