Docosahexaenoic acid supplementation increases prefrontal cortex activation during sustained attention in healthy boys: a placebo-controlled, dose-ranging, functional magnetic resonance imaging study.
BACKGROUND
Emerging evidence suggests that docosahexaenoic acid (DHA, 22:6n-3), the principal omega-3 (n-3) fatty acid in brain gray matter, positively regulates cortical metabolic function and cognitive development. However, the effects of DHA supplementation on functional cortical activity in human subjects are unknown.


OBJECTIVE
The objective was to determine the effects of DHA supplementation on functional cortical activity during sustained attention in human subjects.


METHODS
Healthy boys aged 8-10 y (n = 33) were randomly assigned to receive placebo or 1 of 2 doses of DHA (400 or 1200 mg/d) for 8 wk. Relative changes in cortical activation patterns during sustained attention at baseline and endpoint were determined by functional magnetic resonance imaging.


RESULTS
At 8 wk, erythrocyte membrane DHA composition increased significantly from baseline in subjects who received low-dose (by 47%) or high-dose (by 70%) DHA but not in those who received placebo (-11%). During sustained attention, both DHA dose groups had significantly greater changes from baseline in activation of the dorsolateral prefrontal cortex than did the placebo group, and the low-dose and high-dose DHA groups had greater decreases in the occipital cortex and cerebellar cortex, respectively. Relative to low-dose DHA, high-dose DHA resulted in greater decreases in activation of bilateral cerebellum. The erythrocyte DHA composition was positively correlated with dorsolateral prefrontal cortex activation and was inversely correlated with reaction time, at baseline and endpoint.


CONCLUSIONS
Dietary DHA intake and associated elevations in erythrocyte DHA composition are associated with alterations in functional activity in cortical attention networks during sustained attention in healthy boys. This trial was registered at clinicaltrials.gov as NCT00662142.
McNamara
Robert K
RK
Department of Psychiatry, Center for Imaging Research, Division of Bipolar Disorders Research, University of Cincinnati College of Medicine, Cincinnati, OH 45219-0516, USA. robert.mcnamara@uc.edu
Able
Jessica
J
Jandacek
Ronald
R
Rider
Therese
T
Tso
Patrick
P
Eliassen
James C
JC
Alfieri
David
D
Weber
Wade
W
Jarvis
Kelly
K
DelBello
Melissa P
MP
Strakowski
Stephen M
SM
Adler
Caleb M
CM
D001288:Attention / Q000187:drug effects*; D002540:Cerebral Cortex / Q000187:drug effects / Q000502:physiology; D002648:Child; D019587:Dietary Supplements; D004281:Docosahexaenoic Acids / Q000008:administration & dosage / Q000097:blood / Q000494:pharmacology*; D004912:Erythrocytes / Q000187:drug effects; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D017397:Prefrontal Cortex / Q000187:drug effects* / Q000502:physiology; D011930:Reaction Time / Q000187:drug effects*; D012016:Reference Values
D004281:Docosahexaenoic Acids