MEMORY PERFORMANCE AND AREA-SPECIFIC SELF-REGULATION OF SLOW CORTICALPOTENTIALS - DUAL-TASK INTERFERENCE

We examined the effect of area-specific feedback for slow potentials o n sensorimotor and memory performance under single and dual-task condi tions. Subjects observed a memory set for 400 ms and then determined 5 s later whether a target letter had been contained in the original pr esentation (Sternberg task). After one session of Sternberg-only train ing, feedback training was added for production of negative and positi ve slow potentials area-specifically at F-2, C-z or P-z during the 5-s interval separating the memory set and target probes. Addition of the feedback task resulted in an increase in Sternberg response latency a nd errors which was followed by gradual recovery over five dual-task s essions (recovery not complete for the error measure). Subjects succes sfully regulated their slow potentials, but only in an area-nonspecifi c fashion, even though area-specific control was observed in an earlie r study under a feedback-only condition. Sternberg performance did not depend on whether slow potential negativity or positivity was produce d. These findings indicate that competition between tasks was a more i mportant determinant of performance than was modulation of dendritic p olarization by feedback-induced slow potentials.