Activity in reward-related regions during the outcome period.

<p>The main effect of outcome was associated with increased activity in vmPFC (x = 1, y = 38, z = 10; size = 6008 voxels, PCC (x = –1, y = –29, z = 33; size = 2338 voxels) displayed in the sagittal view on the left. The coronal slice in the middle shows increased activity in bilateral ventral striatum in response to outcome (x = –1, y = 8, z = 5; size = 5239 voxels). The coronal slice on the right shows enhanced signal change in the left amygdala during the outcome phase (x = –25, y = –9, z = –13; size = 947voxels). A = anterior. P = posterior. R = right. L = left.</p

Amygdala activity encoding relative valence and context of outcomes during the outcome evaluation period.

<p>The coronal slice shows the interaction effect between outcome (gain/loss) and social setting (single-player condition/team condition) in the right amygdala. The bar graphs indicate the percent signal change (±SE) for the right amygdala (x = 20, y = –1, z = –7; size = 1065 voxels).</p

Cluster Peak Table for main effect outcome.

<p>p<0.001 FDR corrected.</p

Correlations between differential activity during the outcome phase and personality characteristics.

<p>Each data point represents a measurement from one participant. The solid black lines indicate the linear regression for each panel. Correlation coefficients and statistical significance are denoted in the lower right corner of each panel for gain and loss separately. The numbers in brackets denote the bootstrapped 95% confidence intervals for each correlation coefficient.</p

Experimental Design.

<p>Display of the team condition (first row) and single-player condition (second row). The goal of the game was to come as close to a predefined number with either one die or two dice. In the team condition, the participant played with a partner against another team consisting of two players. In the single-player condition, the participant played alone against another player. An event-related design was used. First the target number was presented for 2s. Then the participant had to choose either one die or two dice within 2s. In the team condition the participant was told how many dice the partner had picked. After the choice period, a short animation of rolling dice was presented for 2s. Finally, the outcome was revealed to the participant for 6s providing information about the goal of the trial, the result of both teams and most importantly the monetary gain or loss. This was followed by a fixation cross in the middle of the screen for 2s. In order to assess affect reactions, we implemented an implicit measure: A Chinese character was presented for 500ms and masked with a scrambled picture for 1500ms. Participants judged the visual pleasantness of each Chinese pictograph (like/dislike). Each trial was completed by a jittered fixation period of 4 to 8s displaying a fixation cross in the middle of the screen.</p

Reaction Times.

<p>Mean reaction times for choice period for single-player and team condition. Error bars represent one standard error. ***Indicates significant difference between conditions at p<0.001.</p

Implicit Affect Measure.

<p>Proportion of “pleasant” responses as a function of outcome. Error bars represent one standard error. *Indicates significant difference between conditions at p<0.05.</p