Dataset Information

Genetic variation of the ?2b-adrenoceptor affects neural correlates of successful emotional memory formation.

ABSTRACT:

Objective

Enhanced memory for emotionally charged events helps us to remember potentially vital information. There are large interindividual differences in emotional-memory enhancement, but little is known about their neurobiological basis. Recently, a functional deletion variant of the gene that codes for the ?2b-adrenoceptor (ADRA2B) has been shown to affect memory for emotional experiences. Initial neuroimaging evidence linked this behavioral effect to increased amygdala activity, but its influence on successful memory processing remains unknown. Therefore, the aim of this study was to investigate the effect of the common deletion in the ADRA2B gene on neural activity related to specific mnemonic processing, successful memory formation, and retrieval.

Methods

Twenty-three noncarriers (10 males) and 28 deletion carriers (13 males) with a mean age of 24 years were investigated while performing an emotional-learning task with sad and happy scenes. Functional magnetic resonance imaging was acquired both during memory formation and retrieval.

Results

Although there were no differences in memory performance between groups, the common deletion variant of ADRA2B was related to enhanced activity in the amygdala and inferior frontal gyrus during successful emotional memory formation, but not retrieval. Deletion carriers showed a larger differential response in these brain regions between later-remembered and later-forgotten stimuli than nondeletion carriers did.

Conclusion

Our results demonstrate that the ADRA2B polymorphism influences emotional memory formation but not memory retrieval in the amygdala and left inferior frontal gyrus.

SUBMITTER: Urner M

PROVIDER: S-EPMC6870193 | biostudies-literature | 2011 Dec

REPOSITORIES: biostudies-literature

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Publications

Genetic variation of the α2b-adrenoceptor affects neural correlates of successful emotional memory formation.

Urner Maren M van Wingen Guido G Franke Barbara B Rijpkema Mark M Fernández Guillén G Tendolkar Indira I

Human brain mapping 20110121 12

<h4>Objective</h4>Enhanced memory for emotionally charged events helps us to remember potentially vital information. There are large interindividual differences in emotional-memory enhancement, but little is known about their neurobiological basis. Recently, a functional deletion variant of the gene that codes for the α2b-adrenoceptor (ADRA2B) has been shown to affect memory for emotional experiences. Initial neuroimaging evidence linked this behavioral effect to increased amygdala activity, but ...[more]

PMID: 21259387

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