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E Czihak

Publications and source records attributed to E Czihak.

6 recordsLinked to original sources
PubMed1988

Visual pattern discrimination at the neuronal and behavioral level: an electrophysiological study on the dorsal lateral geniculate body in freely moving cat.

Cats were trained in a go-no ga visual pattern discrimination task with parallel recordings of single unit activity from the dorsal lateral geniculate body (dLGB). The poststimulus time histograms (PSTHs) evoked by the two different visual patterns were compared for each unit. The go-stimulus, which was rewarded by food, evoked a longer lasting tonic like neuronal response in comparison to the responses evoked by the no go-stimulus which was not rewarded. No differences could be observed regarding the latencies of the first excitatory peak of the PSTHs. The results indicate a modulatory influence upon dLGB unit activity depending on the biological relevance of the stimulus.

Animals↗
PubMed1987

Behaviourally dependent modulation of lateral geniculate unit activity in the freely moving cat.

In 120 neurons of the cat's dorsal lateral geniculate body (dLGB), spontaneous and light-evoked activity was analysed in order to obtain further information on firing characteristics during different behavioural states (quietly sitting, locomotion). Experiments were carried out in freely moving cats, using wireless methods for simultaneous registration of single unit activity and locomotion. During locomotion, an enhancement of neuronal single and pool activity was observed. During locomotor activity, flash-evoked responses were modulated, an increase of response amplitude and a decrease of peak latency in the peristimulus time histogram occurred. The results demonstrate a facilitatory influence on spontaneous and light-evoked activity of dLGB neurones during locomotion. They suggest a non-visual phasic modulation of retino-geniculo-cortical information transfer.

Action Potentials↗
PubMed1983

Audio-visual targeting reaction after unilateral lesions of the superior colliculus in cats.

Cats were trained to visually localize one of eight loudspeakers distributed in different spatial locations. The animals localized the activated sound source through a directed movement of ears, eyes and head towards it. The number of correct targeting reactions triggered by a tone stimulus from different spatial positions was strongly impaired in the operated animals in comparison to controls. The number of correct responses was higher when the tone stimuIus was presented from the side of the lesion. The role of the superior colliculus in the integration of audio-visual targeting reaction is discussed.

Animals↗
PubMed1979

Conditioned audio-visual targeting reflexes in split brain cats.

A conditioned audio-visual targeting reflex was elaborated in 12 freely moving cats. The cats had to localize the loudspeaker emitting by a tone of 1600 Hz, of 500 ms duration and 80 dB intensity. Each time one of the eight loudspeakers placed in front and behind the cat was activated and the targeting reaction rewarded by food. Normal cats attained the 80 percent criterion for the front and rear loudspeakers in 20 and 30 sessions, respectively. The influence of the transection of the corpus callosum on acquisition and retention of the targeting reaction was investigated. The split brain animals with pre-operative experience in the situation did not show any retention, but relearned the targeting of the frontal sources in 20 sessions. No relearning of the posterior sound sources was observed. The animals that had only post-operative training did not reach 80 percent of correct responses in 50 sessions. Corpus callosum transection influences the integration of the targeting reaction in different ways, depending on the position of the sound source and on pre-operative training.

Animals↗