The finding that reversal learning performance (reward processing) was inversely related to impulsivity has also to our knowledge not been observed. This finding suggests that youth with deficits in the ability to adjust to new reinforcement contingencies are more likely to exhibit impulsive tendencies. The finding is consistent with studies of adults who suffered lesions to orbitofrontal brain regions and who also exhibit impulsive decision making (Fellows & Farah, 2003; Rolls, Hornak, Wade, & McGrath, 1994). Youth with such deficits may well develop impulsive styles of behavior that fail to recognize changes in reward contingencies. Furthermore, youth who exhibit weak performance on both working memory and reversal tasks would be expected to develop even greater impulsive behavior styles. Indeed, working memory and reversal learning performance were largely unrelated, consistent with the different brain regions to which they have been associated (dorsolateral for working memory and orbitofrontal for reversal learning).
