The spectral sensitivity of the acuity criterion: Effect of nonlinear summation of isolated parvocellular receptive field centers

摘要: Spectral sensitivity for the detection of acuity targets is additive and indistinguishable from spectral to flicker (Pokorny et al., 1968; Ingling al, 1992). Acuity believed be mediated by color opponent neurons with Type I receptive fields. The Vλ (flicker) approximately 5R+3G while r-g channel 2R-3G. Martinez (1983) showed that luminance gratings should therefore have a 2R+3G, which distinguishable Vλ. Tsou (1987) high frequency (and other targets) do not modulate surrounds cells; therefore, if only centers are active present in same proportions as cones, may reflect pooled, isolated centers, channel. This argument did take into account nonlinear effects probability summation among pooled centers. Modelling indicates does grossly affect shape resulting function. In addition, allowed retain their weights after being stripped modulated surrounds, an 2R:3G actually gives better approximation (5R:3G) than 5R:3G pooling. These results illustrate difficulty working backward mechanisms.