ON DIRECTION-SELECTIVE GANGLION-CELLS IN THE RABBIT RETINA - DENDRITIC MORPHOLOGY AND PATTERN OF FASCICULATION

ON direction-selective (DS) ganglion cells were identified by electrop hysiological recordings in DAPI labeled, isolated rabbit retinas. Thei r responses to a flashing spot were sustained. Their responses to movi ng stimuli were strong in the preferred direction and weak in the null direction. Injection of the recorded cells with Lucifer yellow reveal ed that the cells had a distinct dendritic morphology, consistent with that described previously (Buhl & Peichl, 1986; Amthor et al., 1989; Famiglietti, 1992a). When neighboring cells were injected, an extensiv e dendritic co-fasciculation was observed. The pattern of fasciculatio n restricts the possible synaptic connections of the ON DS cell.