In this study we examined the neural correlates of conflict processing in the Stroop, counting, and digit-location tasks using event-related brain potentials (ERPs). The behavioral data revealed robust interference in response time and accuracy for all tasks. The interference effect for response time was greater in the Stroop task than the other tasks; in contrast, the interference effect for response accuracy was greater in the counting tasks than the other tasks. The N450 and sustained potential (SP) were elicited in each task. Partial least-squares (PLS) analysis was used to examine the structural relationships between the ERPs, task design, and behavior. TaskPLS analysis revealed that the N450 and SP were associated with a single latent variable leading to the suggestion that a common set of neural generators was recruited during conflict processing across the tasks and that there were differences between ERPs related to early processing across the three tasks. BehavioralPLS analysis revealed that the amplitude of the SP was positively correlated with response time and accuracy, indicating that this modulation of the ERPs may be related to response selection rather than to conflict resolution.

Prospective remembering reflects the ability to realize intentions that must be delayed over some period of time. Recent evidence indicates that distinct modulations of the event-related brain potentials may be associated with the detection of a prospective memory cue (N300) and the recovery of an intention from memory (LPC, slow wave). The present experiments examined the degree to which these modulations were influenced by task manipulations that were expected to differentially influence cue detection and memory-related processes. Varying the number of intentions modulated the amplitude of a slow wave that may reflect memory-related processes. In contrast, varying the distinctiveness of the cues modulated the N300 and the early portion of the LPC indicating that this manipulation primarily influenced detection and categorization processes. These findings indicate that the N300, LPC and slow wave reflect functionally distinct processes associated with prospective memory.

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