| The present study surveys the ganglion cells in the rabbit retina, and focuses on investigating a range of properties of the ON-OFF direction-selective (DS) cells.Animals were anaesthetised for surgical procedures with 1-2% halothane and maintained during data collection on 70:30 mixture of nitrous oxide and oxygen supplemented with 15-30 mg/kg/day of α-chloralose by continuous intravenous infusion. The EEG and ECG were monitored continuously. Ocular stability was secured by alcuronium chloride (3 mg/kg/day) and artificial ventilation provided. Extracellular recordings were carried out intraocularly from intact eyes using modified tungsten-in-glass electrodes.Visual stimuli such as flashing spot, drifting sine wave and square wave gratings were generated on a high resolution, high frame rate monitor using an IBM386 compatible computer. Nerve impulses were collected either using a computer gated counter or a digital input-output interface card.Adaptation of the ON-OFF DS cells responses were studied. It mainly occurred in the first 30-40 sec after visual stimulation began, then the responses of the DS cells reached a steady-state.The distribution of the preferred directions was analysed using chi-square analysis, and the number of cells in the group with the preferred directions to the anterior was significantly greater than that in the other three groups. The similar proportion suggested an interesting correlation between the DS cells with the preferred direction to the anterior and the tracer-coupled BiS1 cells.In contrast to the concentric cells, the responsivity of ON-OFF DS cells receptive fields mapped with a small flashing spot were not monotonically reduced from centre to...
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