Brisk and sluggish concentrically organized ganglion cells in the cat's retina

Abstract

SUMMARY1. Nine hundred and sixty cat retinal ganglion cells were evaluated with respect to receptive-field organization and latency to antidromic activation of their axons from optic-tract and mid-brain positions.2. The vast majority (92 %) had the familiar concentric centre/surround organization. As in earlier work these could be classed as sustained or transient, independently of the centre type. About 13 % of the concentric cells were characterized by relatively sluggish responses to conventional visual stimuli which yielded brisk responses from the others. The sluggish cells constituted a previously unspecified class of concentric receptive fields.3. The responses of brisk and sluggish cells to a variety of stimuli were described with a view to developing procedures for distinguishing them on functional grounds.4. Measurements of latency to antidromic activation of retinal axons confirmed earlier work in showing that cells classed as brisk-transient had the shortest conduction times from the optic tract. Cells classed as brisksustained had intermediate conduction times and from earlier work would constitute an important input to the lateral geniculate nucleus. A proportion of the brisk-sustained axons reached the pretectal region (especially on-centre types) and a small minority reached the superior colliculus (especially off-centre types).5. Sluggish cells had generally slower antidromic conduction times; despite some overlap with the brisk-sustained class, the slower conduction provided independent support for the functional differentiation. Sluggish axons reached the pretectal region and superior colliculus. 6. The brisk-sustained cells constituted the majority of the recordings in the area centralis.

Analysis of orientation bias in cat retina

“…The contours were often elliptical (average ratio of major to minor axis 1-23) with the major axis oriented within 200 of the horizontal. Anatomical investigations of cat retinal ganglion cell dendritic fields (Boycott & W. R. LEVICK AND L. N. THIBOS Wassle,1974) indicated an asymmetry of about the same amount (usual ratio 11-12) which is consistent with the commonly held view that dendritic fields correspond closely with the receptive field centres of ganglion cells (Brown & Major, 1966;Honrubia & Elliott, 1970;Boycott & Wiissle, 1974;Cleland-& Levick, 1974;Stone & Fukuda, 1974;Levick, 1975;Peichl & Wiissle, 1979). However, no systematic pattern has yet been reported for the orientations of elongated dendritic fields.…”

“…In a preliminary account of this work, it was shown that most units have some degree of orientation bias and that the response of some units may vary substantially with grating orientation (Levick & Thibos, 1980a). In the present full account of these experiments, an improved measure of orientation bias is introduced and applied in a survey of the behaviour of a substantial number of retinal cells of all the concentric classes (Cleland & Levick, 1974). The variation of orientation bias with spatial frequency is also examined and several control experiments are described which indicate that the effect is of neural, not optical, origin.…”

The influence of stimulus velocity on the responses of single neurones in the striate cortex.

“…In addition it should be appreciated than even in the retina and lateral geniculate nucleus the brisk transient cell's greater responsiveness to rapidly moving stimuli is apparent only for stimuli appropriate to the surround (i.e. a white spot moving into an ON surround) and that sustained cells also fire to rapidly moving stimuli if the contrast is appropriate to the centre of the receptive field (Cleland et al 1971;Cleland & Levick, 1974 Movshon's (1975) population and many of our complex cells responded well to extremely low velocities. However, there was one complex cell, perhaps a representative A. W. GOODWIN AND G. H. HENRY from a larger population, where the optimal velocity was much higher (i.e.…”

Induced movement in the visual modality: An overview.

“…For example, the importance of the inducing stimulus's being peripheral to the induced stimulus in aftereffects of induced movement (Reinhardt-Rutland, 1981 might be related to the relative proportions of neurons with different characteristics across the retina (Cleland & Levick, 1974;Fukuda & Stone, 1974;Hoffman, 1973;Hoffmann, Stone, & Sherman, 1972;Leventhal, 1982): Neurons with sustained response (sometimes labeled X cells) are more characteristic of the central retina, and neurons with transient response (sometimes labeled Y cells) are more characteristic of the peripheral retina. This may be reflected in different patterns of innervation at the lateral geniculate (Friedlander, Lin, Stanford, & Sherman, 1981;Sherman, 1985).…”