Receptive fields and trigger features of ganglion cells in the visual streak of the rabbits retina.

1. A survey of the properties of retinal ganglion cells in the central part of the rabbit retina has been carried out.2. The five types of unit previously encountered in the peripheral retina were also found in the central region. Their receptive fields were smaller, and tended to be oval-shaped with the long axis horizontal.3. In addition, three new types were discovered: orientation-selective cells, local-edge-detectors, uniformity-detectors.4. Orientation-selective cells were sensitive to either vertically or horizontally extended targets. Analysis suggested they were modified concentric units with an incomplete antagonistic surround.5. Local-edge-detectors responded to the appearance or movement of a contrasting border within the receptive field. They were inhibited by similar stimulation of the region surrounding the receptive field. Detailed attention was given to the demonstration of edge-detection.6. Uniformity detectors had a relatively high level of ongoing activity in the absence of stimulation. All forms of stimulation (lights flashed on or off, movement of darker or lighter targets) produced a diminution or cessation of ongoing activity.7. The results are compared with behaviour described in other species.