Single-cell–initiated monosynaptic tracing reveals layer-specific cortical network modules

Abstract

Tracing cells that project to one neuron Feature extraction is a prominent characteristic of cortical neurons involved in the early stages of sensory processing. Wertz et al. retrogradely marked an injected neuron and its direct inputs to reveal the network mechanisms that mediate their response. Neurons within each presynaptic network layer of single direction-selective cells showed similar motion direction preferences. In some networks, layer-specific functional modules were identical to the orientation preference of the postsynaptic neuron. Presynaptic neurons, however, displayed a general bias toward the stimulus feature that elicited a response in the postsynaptic neuron. Science , this issue p. 70