Extended Data Fig. 10: LED illumination alone cannot explain changes to somatic event rate, SD residual, or decoding of task-related variables.
a,b, Viral targeting and imaging/LED stimulation strategy schematic for the activation of NDNF+ interneurons in 4 mice (56 imaging sessions), and for a control group of 9 Rbp4 mice (42 imaging sessions) expressing GCaMP7f in layer 5 neurons and exposed to LED light stimulation without expressing ChRmine in NDNF+ interneurons. c, Same as Fig. 3g, but for NDNF activation experiments. White dashed lines indicate the somatic and dendritic field of view as shown in d. Scale bar = 50 μm d, Somatic and dendritic field of view as indicated by the dashed lines in a. Layer 5 neurons labelled with GCaMP7f. The two images show the artefact produced by the simultaneous imaging and LED illumination for optogenetic stimulation. LED light activates for 6 ms at the beginning of each frame while PMTs stay off for 1 extra ms (7 ms total PMT off time). After the first 7 ms, the LED light turns off while PMTs engage to record GCaMP7f activity for the remainder of the frame. Scale bar = 100 μm. e, Probability distributions of the SD residual for the two groups of mice. For each neuron, the relationship between somatic and dendritic activity was first established during the opto-off condition, and then all events during opto-on were superimposed onto this relationship. An SD residual of 0 means that there is no difference in SD residual during LED light on vs LED light off (t-test, p = 3.37e−136. Mean = −0.1 and −0.9; s.e.m. = −0.02 and 0.02; n = 2087 and 1886 neurons for ChRmine + and ChRmine – groups, respectively). f, Somatic event rate in the groups mice estimated as event rate (Hz) during opto on – opto off (t-test, p = 1.6e−297. Mean = −0.003 and −0.02; s.e.m. = −0.0002 and 0.0004; n = 3481 and 2884 neurons for ChRmine +ve and ChRmine –ve groups, respectively). g, Same as Fig. 4j (left panel, paired t-test, p = 0.001. Mean = 0.62 and 0.57; s.e.m. = 0.02 and 0.02, respectively for test and shuffle data. N = 64 sessions from 5 mice) and for a control group of 5 Rbp4 mice expressing GCaMP7f in layer 5 neurons and exposed to LED stimulation without expressing ChRmine in NDNF+ interneurons. h, Same as Fig. 4l (right panel, paired t-test, p = 0.001. Mean = 0.58 and 0.52; s.e.m. = 0.01 and 0.001, respectively for test and shuffle data. N = 65 sessions in 5 mice) for a control group of 5 Rbp4 mice expressing GCaMP7f in layer 5 neurons and exposed to LED stimulation without expressing ChRmine in NDNF+ interneurons.
