Real-world social decision making often occurs in circumstances where objects
come with some pre-existing tag of emotional valence, so that prejudicial attitudes appear to be based on emotionally-charged labels. However, investigations of race-bias typically do not model the complexity and ambiguity of real-world objects. The Iowa Gambling Task (IGT) provides a paradigm which aims to model real-world complexity, with targets that exhibit ambiguous, ambivalent, and shifting affective properties. The original IGT uses decision targets that hold no pre-existing affective nature at the outset, but targets in the real-world generally possess complex emotional histories, which form the basis of prejudice.
The present study examined the impact of labelling IGT decks with task-irrelevant stimuli that possess pre-existing emotional and/or social salience. Five experiments manipulated the class of deck label (e.g., race) using both congruent and incongruent association to the incentive values of the decks. A final study assessed the impact of lesions of the frontal lobe on performance on this IGT variant.
The experiments demonstrated that an incongruent association between pre-existing emotional valence and deck-rewarding properties can lead to persistent decision-making biases. A common theme was an inability to tolerate the inconsistency between task rewards and irrelevant pre-existing labels. The effects were especially powerful for emotionally salient labels (e.g., race), but were far less powerful for other labels (e.g., facial attractiveness). Frontal lesions also produced a similar decision-making bias, and in one instance generated effects much larger than was observed in other patients or controls.
These findings highlight the importance of pre-existing emotional biases in complex decision-making. The data suggest that ineffective regulation of goal-irrelevant emotion can lead to large and persistent judgmental biases, even when the participant is faced with striking real-world losses.