Theta synchronization and alpha desynchronization in a memory task.
In the present study, we examined the hypothesis that episodic encoding and retrieval processes are primarily reflected by a task-related increase in theta power. Individuals performed a recognition task with a total of 192 words. The electroencephalogram was recorded during the study and recognition phase. The results show that only those words that were later correctly recognized produced a significant increase in theta power during encoding. During the actual recognition processes too, a significant theta synchronization (increase in band power) was found for correctly remembered words only. In contrast to the theta band, remembered and not remembered words revealed a complex pattern of desynchronization in the lower and upper alpha band that was different during encoding and recognition.
Klimesch
W
W
Department of Physiological Psychology, University of Salzburg, Austria. wolfgang.klimesch@sbg.ac.at
Doppelmayr
M
M
Schimke
H
H
Ripper
B
B
D000328:Adult; D000513:Alpha Rhythm; D003344:Cortical Synchronization; D004569:Electroencephalography; D005260:Female; D006801:Humans; D008297:Male; D008568:Memory / Q000502:physiology*; D013647:Task Performance and Analysis; D013826:Theta Rhythm