In the present study we evaluated the relationships
between the P300 event-related potential and event-related
desynchronization (ERD) of electroencephalographic alpha
activity by simultaneously analyzing P300 as well as 7–10-
and 10–14-Hz alpha ERD responses from auditory passive
and active oddball conditions. We compared the effects
of task (target vs. nontarget) and electrode (Fz, Cz, Pz)
on P300 and ERD, and correlated P300 amplitude/latency
with ERD maximal amplitude/latency across individuals.
The major findings were that P300 as well as slow and fast
alpha ERD manifested similar task and electrode effects.
P300 preceded ERD and predicted individual variance of
both slow and fast alpha ERD. The relationships of P300
with alpha ERD were different for the slow and fast alpha
frequencies. These findings indicate that P300 and ERD
are related such that slow and fast alpha ERDs are specifically
guided or modified by the internal event(s) indexed by P300.