Fig. 1: Experimental methods.

a Recording electrode location and optical fiber placement. Subjects were implanted with a 4-shank, 32-channel electrode array, and optogenetic fiber in the right hemisphere of ACx. Each shank contained 8 sites per shank with 100 µm spacing between electrode contacts. Mouse brain illustration from Pixta (https://www.pixtastock.com/illustration/67155575). b Representative local field potential (LFP) activity from one mouse. LFP was used to estimate current source density and the layer of the recording site within each shank (Supplementary Fig. 2). c Example mean single-unit waveform and inter-spike interval (ISI) auto-correlogram. Dashed lines in mean waveform represent one standard deviation above and below the mean, while scale bars are equal to 200 µV and 1 ms. Dashed red lines in the correlogram represent ISIs of ±2 ms. d Schematic for control and optogenetic trial presentation. During approximately 50% of all trials, a 532 nm laser would turn on 50 ms before sound stimulus onset and turn off coincident with sound offset. e Paired comparisons of mean evoked firing rate during control and laser trials. Paired t tests yielded a significant increase in evoked firing rate during optogenetic suppression for clean (n = 43 configurations; P = 4.50e-07, d = −0.91) and masked trials (n = 18 configurations; P = 0.006, d = −0.073).