Event-related desynchronization (ERD) and the Dm effect: Does alpha desynchronization during encoding predict later recall performance?

Author(s): Schimke, H., Doppelmayr, M., Ripper, B., Schwaiger, J., Pfurtscheller, G.

Journal/Book: Int J Psychophysiol. 1996; 24: PO Box 211, 1000 AE Amsterdam, Netherlands. Elsevier Science BV. 47-60.

Abstract: Based on previous research which has shown that event-related desynchronization (ERD) in the lower and upper alpha band reflects attentional and semantic processing respectively, the present study examines the hypothesis whether event-related shifts in the two alpha bands are capable of predicting later recall performance. In an incidental memory paradigm, subjects first had to judge the category membership for a set of 96 words. Later, without prior warning, subjects were asked to recall the words. The results show that for good performers, the extent of ERD in the lower alpha band during the semantic encoding for words is significantly larger for remembered as compared to not remembered words, whereas for bad performers the ERD in the upper alpha band is significantly more pronounced. This type of Dm effect is particularly strong over parietal recording sites in both hemispheres. In referring to the proposed interpretation of the lower and upper alpha band, the present findings seem to indicate that in contrast to good performers, bad performers are less attentive or alert during encoding. Event-related potentials (ERPs) also yielded significant Dm effects at parietal recording sites.

Note: Article Klimesch W, Salzburg Univ, Inst Psychol, Dept Physiol Psychol, Hellbrummerstr 34, A-5020 Salzburg, AUSTRIA

Keyword(s): Dm Effect; ERP; event-related desynchronization (ERD); alpha frequency; semantic encoding; memory performance; RECOGNITION MEMORY; SEMANTIC MEMORY; POTENTIALS; PARADIGM; WORDS; P300; EEG; PATTERNS; PICTURES

Zurück | Weiter