Extended Data Fig. 8: Verification of simultaneous optogenetic activation and neural recording.

(a) Both dopamine and D1 neurons in TS, measured with GRABDA2m and GCaMP7f in Tac1 mice, are sensitive to a visual stimulus on a screen (mean ± SEM, n = 3 animals each). (b) Dopamine axons in TS were optogenetically activated as dopamine sensor signals in the TS were recorded with fiber-fluorometry with or without a strong red LED light (‘masking light’) to mask light illumination for optogenetics. Without masking light, optogenetic stimulation evoked dopamine response artifacts even in control mice with no opsin expression (0-1 s average response, control mice without masking, t-test, p = 0.036, t = 5.10; control mice with masking, t-test, p = 0.69, t = −0.44). Grey bar covers time of optogenetic stimulation (0-0.5 s). mean ± SEM. N = 3 animals for each. (c) Histogram of duration from trigger of monster movement to reward acquisition on monster Day1 in normal mice (n = 6 animals) in the monster paradigm as a reference for choice of optogenetic duration. (d) Left, dopamine responses to a strong novel sensory stimulus that consists of 100 dB complex tone and blue LED light. Arrows indicate onset of the sensory stimulus, each lasts for 0.5 s. Right, dopamine responses to 10, 20 and 40 Hz optogenetic stimulation that last for 0.5 s or 4 s. n = 3 animals for each. (e) Schematic of recording setup using 473 nm and 635 nm lasers to deliver light to record neural signals and to activate neurons, respectively. (f) Distribution of recording fibers to collect dopamine sensor signals.