Fig. 3. Adaptive behavior and S1 responses.

a Manipulation of the stimulus distribution range. Every stimulus is presented with equal probability (P = 0.2). The design involves amplitudes common to both high range (magenta) and low range (green) conditions. b Psychometric curves and response thresholds for an example animal working on both conditions. Each dot corresponds to response probabilities from a single session. Solid curves are logistic fits to the average data (n = 10–11 sessions). Dotted line is a hypothetical curve assuming no change in performance (H₀). Dashed line is a hypothetical curve assuming a change in performance to maintain reward (H₁) when switching from high range to low range stimulus distributions. Response thresholds are shown as vertical lines with 95 % confidence limits. Inset. Response thresholds of all mice (gray symbols). Bars represent means across mice with SD (n = 4). *P = 0.03, two-sided Wilcoxon rank-sum test. c Number of rewards (correct trials) accumulated by the same animal from b. Each line corresponds to one session. Figure conventions are the same as in b. Inset. Average total reward number per session for each mouse. The average number of trials is shown on top. n.s. not significant, P = 0.69, two-sided Wilcoxon rank-sum test. d Frames of evoked cortical fluorescence activity from two example sessions, one with a high range stimulus distribution (left) and the other with a low range stimulus distribution (right). The frames are aligned for amplitudes common to both datasets. Data with a deflection angle of 8 degree was chosen for further analysis (outlined box). e Temporal fluorescent signal in response to 8 degree stimulation, extracted from the region of interest and averaged across sessions and mice. Error bands represent SEM. PSTHs of behavioral lick responses are shown on top. Median reaction times (first lick post stimulus) are shown as arrows, 25–75 percentiles as horizontal lines (n = 829–831 trials). f Observer model based on signal detection theory. Behavioral adaptation can either be induced by changes in sensitivity intrinsic to S1 (d′ in black, top panel), changes in decision criterion by a downstream observer (c in blue, bottom panel), or both. g Top: Distributions of evoked trials (signal) and catch trials (noise) computed separately for the high (HR) and low range (LR) condition. Dashed lines indicate mean ΔF/F₀, black arrows indicate d’ values. Blue lines indicate criterion values as computed from ROC curves. Bottom: C and d′ metrics (neuronal and behavioral). Shown are bootstrapped estimates of means and 95 % confidence limits (n = 38 (LR) or n = 41 (HR) sessions, n = 4 mice, n_boot = 1000 repetitions). ***P < 0.001, n. s. not significant, P = 0.1, two-sided Wilcoxon rank-sum test.