Activity Regulates the Incidence of Heteronymous Sensory-Motor Connections

作者：Mendelsohn Alana I; Simon Christian M; Abbott L F; Mentis George Z; Jessell Thomas M^*

来源：Neuron, 2015, 87(1): 111-123.

DOI：10.1016/j.neuron.2015.05.045

The construction of spinal sensory-motor circuits involves the selection of appropriate synaptic partners and the allocation of precise synaptic input densities. Many aspects of spinal sensory-motor selectivity appear to be preserved when peripheral sensory activation is blocked, which has led to a view that sensory-motor circuits are assembled in an activity-independent manner. Yet it remains unclear whether activity-dependent refinement has a role in the establishment of connections between sensory afferents and those motor pools that have synergistic biomechanical functions. We show here that genetically abolishing central sensory-motor neurotransmission leads to a selective enhancement in the number and density of such "heteronymous'' connections, whereas other aspects of sensory-motor connectivity are preserved. Spike-timing-dependent synaptic refinement represents one possible mechanism for the changes in connectivity observed after activity blockade. Our findings therefore reveal that sensory activity does have a limited and selective role in the establishment of patterned monosynaptic sensory-motor connections.

• 出版日期2015-7-1