Gamma oscillations distinguish true from false memories.
To test whether distinct patterns of electrophysiological activity prior to a response can distinguish true from false memories, we analyzed intracranial electroencephalographic recordings while 52 patients undergoing treatment for epilepsy performed a verbal free-recall task. These analyses revealed that the same pattern of gamma-band (28-100 Hz) oscillatory activity that predicts successful memory formation at item encoding--increased gamma power in the hippocampus, prefrontal cortex, and left temporal lobe--reemerges at retrieval to distinguish correct from incorrect responses. The timing of these oscillatory effects suggests that self-cued memory retrieval begins in the hippocampus and then spreads to the cortex. Thus, retrieval of true, as compared with false, memories induces a distinct pattern of gamma oscillations, possibly reflecting recollection of contextual information associated with past experience.
Sederberg
Per B
PB
University of Pennsylvania, Philadelphia, PA 19104, USA.
Schulze-Bonhage
Andreas
A
Madsen
Joseph R
JR
Bromfield
Edward B
EB
Litt
Brian
B
Brandt
Armin
A
Kahana
Michael J
MJ
D000328:Adult; D002648:Child; D004569:Electroencephalography; D005260:Female; D007839:Functional Laterality / Q000502:physiology*; D006624:Hippocampus / Q000502:physiology*; D006801:Humans; D008297:Male; D011939:Mental Recall; D008875:Middle Aged; D012094:Repression, Psychology; D014825:Vocabulary