Figure 2. Optogenetic stimulation of SF1+ neurons induces freezing and/or activity bursts.
(A) Representative tracking traces (red) of SF1-ChR2 expressing mice before (‘Prelight’) or during (‘Light’) optogenetic stimulation. Red dot in lower image reflects immobility of animal. (B) Representative velocity trace displaying light-elicited freezing (arrow) in a ChR2 mouse. Blue shading represents period of photostimulation. Inset, expanded view of region in dashed box. (C) Percentage of photostimulation trials evoking freezing. (D) Percentage of time spent freezing during photostimulation averaged across trials. (E) Percentage of ChR2-expressing or control eYFP-expressing animals showing photostimulation-evoked freezing behavior. n = 17–18 animals for each group. (F) Representative tracking traces of a SF1-ChR2 expressing mouse (‘Prelight’) or during (‘Light’) optogenetic stimulation. Wider spacing between points in ‘Light’ indicates higher velocity. (G) Representative velocity trace displaying light-induced activity burst behavior in an SF1-ChR2 mouse. Note period of freezing prior to activity burst. Inset, expanded view of region in dashed box. (H) Percentage of stimulation trials evoking activity bursts following freezing. (I) Average velocity during activity burst period. (J) Average onset latency for freezing vs activity burst. n = 9 animals for each condition. Values are displayed as mean ± SEM. ****p < 0.0001; ***p < 0.001; **p < 0.01; *p < 0.05.
Figure 2—figure supplement 1. ChR2-eYFP quantification in the VMHdm/c of freezing only and freezing + activity burst groups.
