An Event Related Potential Study of Skill Learning in Unimpaired Participants

Electroencephalograph (EEG) recordings were analyzed to assess neuronal plasticity associated with cognitive changes during the learning of a new task. Electroencephalograph was recorded in two sessions: one recording session before practice; and a second recording after participants were given five consecutive days of practice with an alphabet addition task. In this task participants were given an equation using letters and numbers and were instructed to indicate whether the candidate answer was true or false (e.g., C+3=F, True; A+D=1, False). In replication of the Romero et al. (2008) study, it was expected to see a reduction in a positive ERP peak at ~300ms and an increase in a positive peak at ~500ms after practice coinciding with skill-related reduction in reaction times, an increase in accuracy, and a switch in cognitive strategy from counting up in the alphabet to retrieving the correct answer from memory. This study differed from the Romero et al. (2008) study in that participants were given a quarter of the practice and new problems were added to the post-practice EEG session. Behavioral results replicated reduced reaction times and a switch in cognitive strategy with practice, but no significant changes in accuracy. Electrophysiological results included a the replication of a reduction in a positive ERP peak at ~300ms which interacted with problem type (i.e., true/false), and a decrease in a positive peak at ~500ms mainly for false medium difficulty problems