" ... Here we present a detailed connectomic reconstruction of SAC circuitry in mouse retina and describe two previously unknown features of synapse distributions along SAC dendrites: input and output synapses are segregated, with inputs restricted to proximal dendrites; and the distribution of inhibitory inputs is fundamentally different from that observed in rabbit retina. An anatomically constrained SAC network model suggests that SAC–SAC wiring differences between mouse and rabbit retina underlie distinct contributions of synaptic inhibition to velocity and contrast tuning and receptive field structure. In particular, the model indicates that mouse connectivity enables SACs to encode lower linear velocities that account for smaller eye diameter, thereby conserving angular velocity tuning. These predictions are confirmed with calcium imaging of mouse SAC dendrites responding to directional stimuli. ..."
Model Type: Synapse; Neuron or other electrically excitable cell
Region(s) or Organism(s): Retina
Cell Type(s): Retina amacrine cell
Model Concept(s): Direction Selectivity; Calcium dynamics
Simulation Environment: NeuronC (web link to model)
References:
Ding H, Smith RG, Poleg-Polsky A, Diamond JS, Briggman KL. (2016). Species-specific wiring for direction selectivity in the mammalian retina. Nature. 535 [PubMed]