Three bands of oscillatory activity in the lateral geniculate nucleus of the cat visual system

Neuronal responses in the cat lateral geniculate nucleus were analyzed with respect to oscillatory components in 5930 peri-stimulus time histograms recorded in 69 neurons. Oscillatory components were observed in three frequency ranges clearly separated from each other, i.e. in a lower range between 25 and 33 Hz (mean 27.8 Hz), in a middle range between 45 and 60 Hz (mean 52.5 Hz), and in a higher range between 75 and 100 Hz (mean 84.4 Hz); temporal variance within the neuronal populations showing oscillatory characteristics increased with higher frequencies. Although the frequency ranges of the oscillatory responses were clearly separated from each other, a functional dependence between these three populations of geniculate neurons appears to be possible; the numerical relationship of approximately 1:2:3 points to the possibility of a temporal coupling between distinct neuronal populations at an early stage of visual processing. (C) 2003 Elsevier Ireland Ltd. All rights reserved.