Extended Data Fig. 2: Reaction times (RT) are higher in loss and for exploration choices.
From: Rate and noise in human amygdala drive increased exploration in aversive learning
(a) Reaction times in gain (blue) and loss (orange) choices. Left: kernel density estimates of RT across all participants and choices. The black line represents the median and the box represents the middle 50% of the distribution (25–75%). Right top: Average RT for each participant across all gain choices (x axis) is significantly smaller than in loss choices (y axis, sign rank test, n = 22, Z = −4.01, p < 10−4). Right bottom: RT as a function of trial during learning, averaged across participants (10 trials running average). (b) Histogram of RT in single trials for exploration and exploitation choices (red/green). Full and dashed lines mark the median and mean presentation time, respectively. (c) The difference in average RT between loss and gain trials is positively correlated with the difference in the proportion of exploration (n = 22, r = 0.65 p = 0.001), suggesting that participants with longer loss-related RT compared to gain-related RT also explored more in loss compared to gain. (d) Average RT for participants in exploration versus exploitation choices in gain and loss (left), and distributions of RT of exploration/exploitation choices in gain and loss trials across all participants (right). There was a significant interaction between EE and valence (n = 3262, F(1,3258) = 13.23, p < 10−3), with a larger RT in gain-exploration compared to gain-exploitation (n = 1631, t1629 = 6.6, p < 10−10, dcohen = 0.67) and no difference between loss-exploration and loss-exploitation (n = 1631, t1629 = 0.65, p > 0.5).
