Intensity coding and luxotonic activity in the ground squirrel lateral geniculate nucleus.
The responses of contrast-sensitive cells in the ground squirrel LGN were studied. In most cells the response to an on-off stimulus was comprised of two components: a sustained on and a transient on-off. The sustained component amplitude was a power function of the light intensity and disappeared altogether at low temperature while the transient component was insensitive to the light intensity and to a drop in temperature. These cells were also luxotonic; they increased their average firing rate when the intensity of a steady stimulus was increased. The possible relation of the luxotonic activity to the diurnal nature of the ground squirrel is discussed.
Gur
M
M
Department of Biomedical Engineering, Technion, Israel Institute of Technology, Haifa.
D000200:Action Potentials; D000818:Animals; D001831:Body Temperature; D003080:Cold Temperature; D005829:Geniculate Bodies / Q000502:physiology*; D008027:Light; D010783:Photometry; D012589:Sciuridae / Q000502:physiology*; D013997:Time Factors