Temporal dynamics of attitude decisions: A test of the iterative reprocessing model using event-related potentials

Although evaluative judgments are a central component of everyday decision making little is known about the temporal dynamics of the processes used to make them. The present study used the high temporal resolution of event-related brain potentials (ERPs) to test Cunningham and Zelazo's (2007) posited differences in the timing of attitude tag retrieval relative to stimulus categorization for 'attitudes' and 'evaluations,' as well as tenets of their Iterative Reprocessing (IR) loop model. Participants made agree/disagree decisions about their attitudes and You/Not You decisions about their autobiographical memories in separate reaction time (RT) tasks while brain activity was recorded from 32 scalp sites. A median-split analysis on RT was used to separate fast and slow decisions. Decisions about autobiographical stimuli produced the typical results in which retrieval and stimulus categorization occurred together just before the response regardless of decision difficulty. By contrast, the relative timing of tag retrieval and categorization differed with difficulty for attitude decisions as predicted by the model. Fast attitude decisions were processed similarly to fast You decisions with retrieval and categorization timing coupled to the response. Slow attitude decisions, however, differed because, while tag retrieval timing was the same as for fast attitude decisions, post-retrieval processing delayed stimulus categorization and a response by 450 msec. ERP activity over dorsolateral prefrontal cortex (DLPFC) in the pre-response interval was asymmetrical, with greater activity for attitude and autobiographical decisions over left and right hemispheres, respectively, while amplitude and duration increased with decision difficulty for both. Slow attitude decisions alone elicited a reduced pre-response positivity, a correlate of goal-directed response selection. The results provide empirical support for key aspects of Cunningham and Zelazo's (2007) attitude-evaluation dichotomy and the timing of the posited component processes in their IR model as well as novel information about the roles of stored tags and reflective processes in different attitude decisions.