Fig. 4: Population coding of aversive CS2 and US2 by D1- and D2-MSNs.
A Aversive Pavlovian conditioning involved learning to associate an auditory cue (CS2; 3-kHz tone) with a 0.5 mA 1 s foot shock (US2). B, C Freezing response progression over trials of the aversive conditioning session for D1-cre (4B: Friedman test; 4 C: two-tailed paired t-test) and D, E A2A-cre mice (4D: Friedman test; 4E: two-tailed paired t-test; nD1-cre = 14, nA2A-cre = 12). F Heatmaps representing D1-MSN responses to CS2 (left) and US2 (right). In heatmaps, neurons are aligned to response to CS2. G Percentage of each type of D1-MSNs response during the initial trials (1-2), last trials (6-7) and all trials. H Pie chart demonstrating that the percentage of CS-US-responsive D1-MSNs does not substantially change throughout trials. I Heatmaps representing D2-MSN responses to CS2 (left) and US2 (right). J Percentage of each type of D2-MSNs response. K Pie chart demonstrating that the percentage of CS-US-responsive D2-MSNs does not change throughout trials. L PSTHs of cue-excited or N cue-inhibited D1-MSNs or P–R D2-MSNs tracked on different trials. M–O AUCs of cue response (0–3 s from cue onset) for D1- or Q–S D2-MSNs over the days. No major differences were observed in the magnitude of responses throughout trials. T Activity of individual D1-MSNs from the first 2 trials and to the last 2 trials, showing variability in individual responses over trials; similar findings were observed for U D2-MSNs. V Cartoon depicting population based SVM decoder (features: population activity during stimulus; observations: average activity during given trial, output: CS2 or US2). W SVM classification accuracy for every mouse using population activity during CS2 and US2 (0-3 s from CS or US onset) for D1-MSNs or X D2-MSNs (two-tailed unpaired t-test). D2-MSNs population activity was more accurate in the categorization of CS2 and US2 events than D1-MSNs. Data are presented as mean values +/−SEM. ***p < 0.001. Source data are provided as a Source Data file. Created in BioRender. Pinto, L. (2024) BioRender.com/p41z755.
