Topographic and Event-Related Potential Correlates of Task Type and Task Difficulty

Abstract : This experiment examined the topographical pattern of event related potentials (ERPs) in three separate tasks whose solution primarily engaged different components of human information processing capabilities. The tasks were stimulus degradation, linguistic, and mathematical processing. In addition, the impact of differing task difficulty on characteristics of the evoked patterns was assessed. The results indicate that the pattern of electrical activity evoked by the tasks was quite similar in the first 200 ms following trial onset. The topography of later ERP components (200 ms post-trial onset) however, evidenced unique response patterns, suggesting that these components may serve as reliable indices of the type of cognitive processing being employed. Increasing task difficulty had little effect on the overall pattern of evoked response, but did selectively alter the amplitude and/or latency of components within particular tasks.