Fig. 2: Reciprocal interactions between pulse-producing and sine-producing neurons in the presence of a female.
From: Flexible circuit mechanisms for context-dependent song sequencing
a, Broad-range optogenetic stimulation of song neurons pIP10 and TN1 (see Methods). One block is 15 trials for 8 s each. Neuron schematic in a was adapted from ref. 5, Elsevier, and ref. 14, Elsevier, under a Creative Commons licence CC BY 4.0. b, Song production per trial and time-resolved song probabilities across trials following optogenetic activation of pIP10 neurons in a solitary male. Responses are shown for 3 out of 20 randomized stimulus blocks. Pulse and sine probability for the third example stimulus block, averaged across n = 20 recordings (bottom). Rebound sine is the production of sine song immediately following pulse song production. Opto stim, optogenetic stimulation. c–e,h–j, Average song probabilities (b) for all stimulus blocks (distinct stimuli per pair of rows); activation of pIP10 (c–e) or TN1 (h–j) in solitary males (c,h), males paired with a wild-type female (d,i) and decapitated solitary males (e,j). f, Rebound sine probability following activation of pIP10 neurons (highest irradiance level only) in solitary, female-paired or headless males. Female presence promotes complex bout (pulse followed by rebound sine) generation following pIP10 activation. g,l, Average duration of song bouts generated via activation of pIP10 (g) or TN1 (l) neurons in solitary, female-paired or headless males. Female presence promotes longer song bouts following activation of either neuron type. k, Rebound pulse probability following activation of TN1 neurons (highest irradiance level only) in solitary, female-paired or headless solitary males. Female presence promotes complex bout generation (sine followed by rebound pulse) following TN1 activation. m, Simplified circuit model of song pathway; female cues ‘unlock’ complex bout generation via modulation of post-inhibitory (post-inh) rebound excitability (exc) in pulse-driving and sine-driving neurons of the ventral nerve cord (VNC). Disinh., disinhibition. Pir, post-inhibitory rebound. For c–g, n = 20 (solitary), 20 (with female) and 10 (headless) males (biological replicates). For h–l, n = 23 (solitary), 28 (with female) and 10 (headless) males (biological replicates). For f,g,k,l, Wilcoxon rank-sum test for equal medians. *P < 0.05, **P < 0.01 and ***P < 0.001. Central mark indicates the median; the bottom and top edges of the box indicate the 25th and 75th percentiles, respectively.Whiskers extend to 1.5 times the interquartile range away from the box edges.
