Receptive-field properties of Q retinal ganglion cells of the cat.

Biomedical Engineering Department, Robert R. McCormick School of Engineering and Applied Sciences, Northwestern University, Evanston, IL 60208, USA.
Visual Neuroscience (Impact Factor: 1.68). 03/1995; 12(2):285-300. DOI: 10.1017/S0952523800007975
Source: PubMed

ABSTRACT The goal of this work was to provide a detailed quantitative description of the receptive-field properties of one of the types of rarely encountered retinal ganglion cells of cat; the cell named the Q-cell by Enroth-Cugell et al. (1983). Quantitative comparisons are made between the discharge statistics and between the spatial receptive properties of Q-cells and the most common of cat retinal ganglion cells, the X-cells. The center-surround receptive field of the Q-cell is modeled here quantitatively and the typical Q-cell is described. The temporal properties of the Q-cell receptive field were also investigated and the dynamics of the center mechanism of the Q-cell modeled quantitatively. In addition, the response vs. contrast relationship for a Q-cell at optimal spatial and temporal frequencies is shown, and Q-cells are also demonstrated to have nonlinear spatial summation somewhat like that exhibited by Y-cells, although much higher contrasts are required to reveal this nonlinear behavior. Finally, the relationship between Q-cells and Barlow and Levick's (1969) luminance units was investigated and it was found that most Q-cells could not be luminance units.

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