(a) BOLD and DA responses to reward prediction errors (RPEs). (i) BOLD response to positive (green trace, N = 5143) and negative (red trace, N = 5591) RPEs. A star represents difference significant at p < .05, FWER corrected, two-tailed. (ii) DA response to positive (green trace, N = 1018) and negative (red trace, N = 991) RPEs. Differences p > .05, FWER corrected, two-tailed. (b) BOLD and DA responses RPEs with BET greater than or equal to 0.9. (i) Bold response to positive (green trace, N = 675) and negative (red trace, N = 679) RPEs and BET greater than or equal to 0.9. A star represents difference significant at p < .05, FWER corrected, two-tailed. (ii) DA response to positive (green trace, N = 238) and negative (red trace, N = 216) RPEs with BET greater than or equal to 0.9. A star represents difference significant at p < .05, FWER corrected, two-tailed.