Fig. 2

Functional verification of ChR2 in vitro (a-d) and in vivo (E-H). a Horizontal brain slice (400 μm) that contained the nRT and thalamus. b nRT neurons in response to 10 Hz, 20 Hz, 50 Hz, 100 Hz, 20 ms, 50 ms, 100 ms, and 1 s light stimulation. c Spikes from nRT (left) and thalamocortical relay neurons (TC) (right) neurons in response to light stimulation. Multi-unit activity in the nRT significantly increased during light stimulation. Multi-unit activity in the thalamus was slightly enhanced during light stimulation and significantly increased 500 ms after light stimulation (blue). d Averaged spike counts from nRT and thalamus neurons in response to different pulse durations of light stimulation. e Position of optoelectrode aligned on the histology atlas. Upper channels 3–7 are in the nRT. (Right) Summation of multi-unit activity from 10 sweeps. During laser stimulation (100 ms blue line), spike activity was evoked in channels that were located in the nRT. f Position of optoelectrode aligned on the histology atlas. Upper channels 2–9 are in the thalamus. (Right) Summation of multi-unit activity from 10 sweeps. During laser stimulation (blue line), spike activity decreased and rebounded in channels that were located in the thalamus. g Multi-unit activity from 20 sweeps in channel 4 in the nRT. h Multi-unit activity from 20 sweeps in channel 3 in the thalamus. During laser stimulation, multi-unit activity in the thalamus significantly decreased and rebounded after laser stimulation was terminated