Main results – differences between conditions.

Note. ES = effect size, CI = confidence interval, * p<.05, ** p<.01, *** p<.001. Results are depicted in such a way that positive numbers indicate a positive change (that is (i) a higher positive than negative bias after training, (ii) an increase in positive bias from pre- to post-training, and (iii) a decrease in negative mood from pre- to post-training; 1positive values reflect higher positive than negative bias; 2positive values reflect increase in positive bias; 3positive values reflect decrease in negative mood; 4negative values reflect increase in negative mood.