Variation of human amygdala response during threatening stimuli as a function of 5'HTTLPR genotype and personality style.
BACKGROUND
In the brain, processing of fearful stimuli engages the amygdala, and the variability of its activity is associated with genetic factors as well as with emotional salience. The objective of this study was to explore the relevance of personality style for variability of amygdala response.


METHODS
We studied two groups (n=14 in each group) of healthy subjects categorized by contrasting cognitive styles with which they attribute salience to fearful stimuli: so-called phobic prone subjects who exaggerate potential environmental threat versus so-called eating disorders prone subjects who tend to be much less centered around fear. The two groups underwent functional magnetic resonance imaging (fMRI) at 3T during performance of a perceptual task of threatening stimuli and they were also matched for the genotype of the 5' variable number tandem repeat (VNTR) polymorphism in the serotonin transporter.


RESULTS
The fMRI results indicated that phobic prone subjects selectively recruit the amygdala to a larger extent than eating disorders prone subjects. Activity in the amygdala was also independently predicted by personality style and genotype of the serotonin transporter. Moreover, brain activity during a working memory task did not differentiate the two groups.


CONCLUSIONS
The results of the present study suggest that aspects of personality style are rooted in biological responses of the fear circuitry associated with processing of environmental information.
Bertolino
Alessandro
A
Psychiatric Neuroscience Group, Section on Mental Disorders, Department of Psychiatric and Neurological Sciences, University of Bari, Bari, Italy. bertolia@psichiat.uniba.it
Arciero
Giampiero
G
Rubino
Valeria
V
Latorre
Valeria
V
De Candia
Mariapia
M
Mazzola
Viridiana
V
Blasi
Giuseppe
G
Caforio
Grazia
G
Hariri
Ahmad
A
Kolachana
Bhaskar
B
Nardini
Marcello
M
Weinberger
Daniel R
DR
Scarabino
Tommaso
T
D000328:Adult; D000679:Amygdala / Q000098:blood supply / Q000502:physiology*; D000704:Analysis of Variance; D001931:Brain Mapping; D015331:Cohort Studies; D005239:Fear / Q000502:physiology*; D001068:Feeding and Eating Disorders / Q000503:physiopathology; D005260:Female; D007839:Functional Laterality; D005838:Genotype; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods; D016014:Linear Models; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D008562:Membrane Glycoproteins / Q000235:genetics*; D026901:Membrane Transport Proteins / Q000235:genetics*; D008570:Memory, Short-Term / Q000502:physiology; D018598:Minisatellite Repeats / Q000235:genetics*; D009419:Nerve Tissue Proteins / Q000235:genetics*; D009483:Neuropsychological Tests / Q000706:statistics & numerical data; D010100:Oxygen / Q000097:blood; D010551:Personality / Q000235:genetics / Q000502:physiology*; D010698:Phobic Disorders / Q000503:physiopathology; D010775:Photic Stimulation / Q000379:methods; D011930:Reaction Time / Q000502:physiology; D050486:Serotonin Plasma Membrane Transport Proteins
D008562:Membrane Glycoproteins; D026901:Membrane Transport Proteins; D009419:Nerve Tissue Proteins; C493230:SLC6A4 protein, human; D050486:Serotonin Plasma Membrane Transport Proteins; D010100:Oxygen