Alcoholism and dampened temporal limbic activation to emotional faces.
BACKGROUND
Excessive chronic drinking is accompanied by a broad spectrum of emotional changes ranging from apathy and emotional flatness to deficits in comprehending emotional information, but their neural bases are poorly understood.


METHODS
Emotional abnormalities associated with alcoholism were examined with functional magnetic resonance imaging in abstinent long-term alcoholic men in comparison to healthy demographically matched controls. Participants were presented with emotionally valenced words and photographs of faces during deep (semantic) and shallow (perceptual) encoding tasks followed by recognition.


RESULTS
Overall, faces evoked stronger activation than words, with the expected material-specific laterality (left hemisphere for words, and right for faces) and depth of processing effects. However, whereas control participants showed stronger activation in the amygdala and hippocampus when viewing faces with emotional (relative to neutral) expressions, the alcoholics responded in an undifferentiated manner to all facial expressions. In the alcoholic participants, amygdala activity was inversely correlated with an increase in lateral prefrontal activity as a function of their behavioral deficits. Prefrontal modulation of emotional function as a compensation for the blunted amygdala activity during a socially relevant face appraisal task is in agreement with a distributed network engagement during emotional face processing.


CONCLUSIONS
Deficient activation of amygdala and hippocampus may underlie impaired processing of emotional faces associated with long-term alcoholism and may be a part of the wide array of behavioral problems including disinhibition, concurring with previously documented interpersonal difficulties in this population. Furthermore, the results suggest that alcoholics may rely on prefrontal rather than temporal limbic areas in order to compensate for reduced limbic responsivity and to maintain behavioral adequacy when faced with emotionally or socially challenging situations.
Marinkovic
Ksenija
K
Department of Radiology, University of California, San Diego, CA, USA. xenia@ucsd.edu
Oscar-Berman
Marlene
M
Urban
Trinity
T
O'Reilly
Cara E
CE
Howard
Julie A
JA
Sawyer
Kayle
K
Harris
Gordon J
GJ
D000818:Animals; D001253:Astrocytes / Q000187:drug effects; D001369:Axons / Q000187:drug effects*; D015153:Blotting, Western; D002217:Carbachol / Q000494:pharmacology; D002478:Cells, Cultured; D002492:Central Nervous System Depressants / Q000494:pharmacology*; D017077:Culture Media, Conditioned; D000431:Ethanol / Q000494:pharmacology*; D048049:Extracellular Signal-Regulated MAP Kinases / Q000378:metabolism; D005260:Female; D006624:Hippocampus / Q000166:cytology* / Q000187:drug effects / Q000254:growth & development*; D007150:Immunohistochemistry; D018721:Muscarinic Agonists / Q000494:pharmacology; D009474:Neurons / Q000187:drug effects*; D011247:Pregnancy; D011493:Protein Kinase C / Q000378:metabolism; D051381:Rats; D043643:Receptor, Muscarinic M1 / Q000187:drug effects / Q000502:physiology; D011976:Receptors, Muscarinic / Q000187:drug effects*; D013778:Tetrazolium Salts; D013844:Thiazoles
D002492:Central Nervous System Depressants; D017077:Culture Media, Conditioned; D018721:Muscarinic Agonists; D043643:Receptor, Muscarinic M1; D011976:Receptors, Muscarinic; D013778:Tetrazolium Salts; D013844:Thiazoles; D000431:Ethanol; D002217:Carbachol; D011493:Protein Kinase C; D048049:Extracellular Signal-Regulated MAP Kinases; C022616:thiazolyl blue