Neural correlates of successful and unsuccessful verbal memory encoding.
Recent neuroimaging studies suggest that episodic memory encoding involves a network of neocortical structures which may act interdependently with medial temporal lobe (mTL) structures to promote the formation of durable memories, and that activation in certain structures is modulated according to task performance. Functional magnetic resonance imaging (fMRI) was used to determine the neural structures recruited during a verbal episodic encoding task and to examine the relationship between activation during encoding and subsequent recognition memory performance across subjects. Our results show performance-correlated activation during encoding both in neocortical and medial temporal structures. Neocortical activations associated with later successful and unsuccessful recognition memory were found to differ not only in magnitude, but also in hemispheric laterality. These performance-related hemispheric effects, which have not been previously reported, may correspond to between-subject differences in encoding strategy.
Casasanto
Daniel J
DJ
Department of Neurology, University of Pennsylvania Medical Center and Brain Imaging Center, Philadelphia 19104, USA.
Killgore
William D S
WD
Maldjian
Joseph A
JA
Glosser
Guila
G
Alsop
David C
DC
Cooke
Ayanna M
AM
Grossman
Murray
M
Detre
John A
JA
D000293:Adolescent; D000328:Adult; D003071:Cognition / Q000502:physiology; D005260:Female; D007839:Functional Laterality / Q000502:physiology; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008568:Memory / Q000502:physiology*; D013702:Temporal Lobe / Q000033:anatomy & histology / Q000502:physiology; D014825:Vocabulary