Response properties of relay cells in the A laminae of the cat's dorsal lateral geniculate nucleus after
saccades
W. H. Fischer, M. Schmidt, V. Stuphorn & K.-P. Hoffmann
Experimental Brain Research, 110:435-445, 1996
- Responses of relay cells in the A-laminae of the dorsal lateral geniculate nucleus (LGNd) during spontaneous
saccades and saccade-like visual stimulation were extracellularly recorded in awake cats. Ninety-six out of 37
cells recorded (42 X and 54 Y cells) were responsive during spontaneous saccadic eye movements. All Y cells and
67% of the X cells responded with burst activity, i.e. with either one or two activity peaks during and after saccades.
Thirty-three percent of the X cells were inhibited during saccades. Excitatory peaks occurred at mean latencies
of 33 ms and 31 ms for X and Y cells, respectively. Comparable burst responses were obtained when retinal image
shifts similar to those during saccades were induced by external saccade-like stimulus movements. However, the
latencies of excitatory peak activity were significantly longer to external stimuli than to the onsets of saccades.
This indicates the existence of an eye movement-related input which activates LGNd relay cells in addition to the
visual input. We propose that the pretectogeniculate projection may contribute to the responses of LGNd relay cells
following saccadic eye movements via a disinhibitory input and that this input could be involved in intra- and
postsaccadic modulations of the transfer of visual signals to visual cortex.
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