Contributions of Y- and W-cell pathways to response properties of cat superior colliculus neurons: comparison of antibody- and deprivation-induced alterations

Abstract

The cat's superior colliculus (SC) receives direct inputs from retinal W-cells (a W-D input) and Y-cells (Y-D input) and an indirect Y-cell input via the lateral geniculate nucleus and visual cortex (Y-I input). In previous studies we have shown that intraocular injection of antibodies raised against large retinal ganglion cells produces a dose-dependent reduction in the Y retinogeniculate pathway. Furthermore, when a sufficiently high antibody concentration is used, there is a substantial loss of the Y pathway and no apparent loss of the W pathway. In the present study, we used the antibodies to investigate the contributions of the Y and W pathways to functional organization within the SC. Binocular injections of low (330 micrograms/100 microliters) or high (1,000 micrograms/100 microliters) antibody concentrations were made. The antibody-mediated effects on SC cells' response properties were compared directly with effects of early binocular deprivation, which have been attributed to a loss of Y-I input. Extracellular single-cell recordings were made from the SC, and cells were classified as receiving Y-D, Y-I, or W-D inputs on the basis of their response latencies to electrical stimulation of the optic chiasm and optic tract. Injections of the low antibody concentration produced no significant effects on inputs to the SC. However, injections of the high antibody concentration resulted in a 70% reduction in SC cells with a Y-D input and an 82% reduction in SC cells with a Y-I input. There was no effect on the percentage of cells with a W-D input. Binocular deprivation produced a 76% reduction in the percentage of cells with Y-I input. Visual response properties of SC cells also were assessed. Injections of the high antibody concentration produced a 55% reduction in cells that respond with a directional preference and a 51% reduction in cells that respond to high-velocity stimuli. Binocular deprivation produced a 78% reduction in the proportion of directional cells and a 25% reduction in cells that respond to the ipsilateral eye. Taken together, the results of this and previous studies using cortical lesions, visual deprivation, and immunoablation suggest that Y-D input is the primary basis for responses to high stimulus velocity, Y-I input is an important basis for directional responses and response through the ipsilateral eye, and W-D input is important for responses to low stimulus velocity.(ABSTRACT TRUNCATED AT 400 WORDS)

Dose-response analysis of effects of antibodies to large ganglion cells on the cat's retinogeniculate pathways

“…Further evidence that the antibodies have no effect on W-cells is provided by a recent study of the superior colliculus in cats given binocular injections of the highest antibody concentration (Crabtree et al, 1984). These cats had a substantial loss of the Y-cell inputs to the superior colliculus, but there was no loss of the W-cell inputs.…”

Spatio-temporal receptive-field structure of phasic W cells in the cat retina

“…The majority of cells have on-off receptive fields, although on and off-center receptive fields are present. The proportion of directionally selective cells in the SGS is also much higher than among retinal phasic W cells, but previous work clearly suggests that directional selectivity is generated within the colliculus, and is at least partially dependent on cortico-tectal input Rizzolatti et al, 1970;Rosenquist & Palmer, 1971;Berman & Cynader, 1972;Ogasawara et al, 1984;Crabtree et al, 1986). Despite their large size, collicular cells respond best to small moving stimuli, and are inhibited by peripheral stimulation, i.e.…”

“…The receptive fields of SGS cells are distinctly larger than those of most retinal phasic W cells, and the proportion of on-off cells in the SGS appears to be greater than is found among retinal phasic W cells, both of which are consistent with other physiological evidence (Mcllwain, 1978;Berson, 1988a) that SGS receptive fields are formed by a convergence of retinal inputs. The proportion of directionally selective cells in the SGS is also much higher than among retinal phasic W cells, but previous work clearly suggests that directional selectivity is generated within the colliculus, and is at least partially dependent on cortico-tectal input Rizzolatti et al, 1970;Rosenquist & Palmer, 1971;Berman & Cynader, 1972;Ogasawara et al, 1984;Crabtree et al, 1986). Since it is not known how inputs from individual retinal W cells contribute to the formation of collicular receptive fields, it is entirely possible that signals from on, off, on-off, and perhaps even directionally selective retinal cells are combined within the SGS to produce the high proportion of large, on-off, directionally selective receptive fields that are found there.…”

“…To be regarded as a feature detector, a cell's output must reliably and unambiguously signal the presence of that feature. The manner in which these signals are relayed to the deeper layers of the colliculus is not clear, although it is likely to involve interactions with direct and indirect Y-cell pathways to these layers (Crabtree et al, 1986;Berson, 1988a). Since their earliest descriptions, it has been clear that phasic W cells respond better to moving than to stationary stimuli.…”

Visible Distortion Predictors Based on Visual Attention in Color Images

“…It is believed that visual attention is not driven by a specific feature that has dedicated low-level properties that can be treated by the HVS-based assessment. Visual attraction can be induced by either heterogeneous or homogeneous, dark or bright, symmetric or asymmetric objects [11], which is determined by higher level processing than the existing HVS-based system. It can be assumed that image information that is rare in the image, such as high frequency areas or higher contrast areas, will draw more attention.…”