Abstract
Previous studies have demonstrated that interference is reduced following external conflict that is defined by stimulus properties. This reduced interference represents a decreased level of internal conflict during the observer’s decision–making process. However, it is unknown whether the magnitude of internal conflict influences subsequent behavior in the same way that external conflict does. To concurrently examine the role of both external and internal conflict on subsequent behavior, we used a visually-guided reaching task in which reach trajectory reflects continuous changes of internal competition during decision-making processes. We asked observers to reach towards a unique shape target among distractors. In the low external conflict condition, all distractors were homogenously colored. In the high external conflict condition, one distractor was uniquely colored, which typically results in attentional capture. Regardless of the external conflict condition, we classified trials as either high or low internal conflict based on the magnitude of reaching curvature towards distractor stimuli. Reach trajectory curvature towards distractor stimuli was reduced following high external conflict trials compared to low external conflict trials. This suggests that in accord with previous studies, external conflict results in reduced interference, and thus reduced internal conflict, during the ensuing trials. However, the magnitude of curvature towards distractors was increased following trials with high internal conflict compared to low internal conflict. This demonstrates that in contrast to high external conflict, high internal conflict predicts increased interference in later behavior. Thus, we suggest that external and internal conflict have opposite effects on subsequent behavior.
Meeting abstract presented at VSS 2012