Polyaxonal A1 amacrine cells form a spatially extended network in primate retina

Polyaxonal A1 amacrine cells in primate retina form a spatially extended inhibitory network, with A1 spike amplitudes declining during bursts and some spikes failing to propagate.

• Why it matters: Inhibitory circuits integrate signals across space, but retinal inhibitory network organization and how specific neuron types connect to output pathways remain poorly understood.
• What they did: Using multielectrode arrays, the study identified A1 amacrine cells by matching properties of morphologically identified A1 cells from single-cell recordings to putative array A1s, then linked them to recursive bistratified ganglion cells via electrical coupling.
• The result: A1 and recursive bistratified cells share receptive-field asymmetry (larger On than Off centers), and electrical-image analyses suggest burst-linked amplitude declines may impair propagation through A1 axonal arbors.