Modulation of Circuit Feedback Specifies Motor Circuit Output

摘要: Bidirectional communication (i.e., feedforward and feedback pathways) between functional levels is common in neural systems, but most systems little known regarding the function modifiability of pathway. We are exploring this issue crab (Cancer borealis) stomatogastric nervous system by examining bidirectional projection neurons their target central pattern generator (CPG) circuit neurons. Specifically, we addressed question whether peptidergic post-oesophageal commissure (POC) trigger a specific gastric mill (chewing) motor ganglion solely activating neurons, or additionally altering strength CPG to these The POC-triggered rhythm shaped inhibition onto from neuron. Here, establish that POC stimulation triggers long-lasting enhancement feedback-mediated IPSC/Ps which persists for same duration as POC-gastric rhythms. This strengthened appears result presynaptic modulation, because it also occurs other whose activity does not change after stimulation. To determine synapse, compared influence dynamic-clamp-injected IPSPs pre- post-POC amplitude into pivotal neuron Only elicited enabled full expression rhythm. Thus, modifiable can be instrumental selection.