Chunk #45 — SUD Prevalence and qEEG Changes — qEEG in Substance Use Disorders — P300 Abnormalities in Cocaine, Methamphetamine, Heroin Addiction, and Alcoholism
elicit a parietal P300, so called P3b (Katayama and Polich 1996, 1998). The P3a is recorded at the anterior scalp locations and has been interpreted as reflecting frontal lobe activity (Gaeta et al. 2003; Knight 1984). Though the P300 response in general is thought to represent “context updating/closure,” in a three-stimuli oddball task the P3a is interpreted as “orienting,” and the P3b is viewed as an index of the ability to maintain sustained attention to target (Näätänen 1990). The anterior P3a indexes the contextual salience of the rare stimuli, whereas the posterior P3b is indexing task-relevance of the stimuli (Gaeta et al. 2003).
