Figure 4. Experiment 2: behavioural results.
(a) Model comparison showed that TD model fitted choices best (Bayesian: hierarchical Bayesian model, HMM: hidden Markov model, Hybrid: action-learning model with associability as changing learning rate). (b) SCRs measured on the side with thermal stimulation (‘Stim side’, left hand) were lower than those on without stimulation (‘Non-stim side’, right hand), but both were highly correlated. (c) Associability from state-learning hybrid model fit SCRs best, similarly to Experiment 1. (d) Trial-by-trial associability from hybrid model fitted pain ratings best compared with other uncertain measures (entropy: HMM entropy, surprise: TD model prediction error magnitude from previous trial, null model: regression with no predictors). (e) Regression coefficients with associability as uncertainty predictor were significantly negative across subjects.
Figure 4—figure supplement 1. Experiment 2: raw skin conductance traces, where vertical lines are beginning of each trial when cue display starts (n = 20, excluded participants not shown, showing first non-excluded session from all participants).
Figure 4—figure supplement 2. Experiment 2: filtered skin conductance traces (band-pass at 0.0159–2 Hz, 1 st order Butterworth), averaged across all trials within participant (n = 20, excluded participants not shown, shaded region represent SEM across all participants).
Figure 4—figure supplement 3. Experiment 2: model protected exceedance probability.
