TY  - JOUR
PY  - 2011//
TI  - Abnormal Hypothalamic Response to Light in Seasonal Affective Disorder
JO  - Biological psychiatry
A1  - Vandewalle, Gilles
A1  - Hébert, Marc
A1  - Beaulieu, Catherine
A1  - Richard, Laurence
A1  - Daneault, Véronique
A1  - Garon, Marie-Lou
A1  - Leblanc, Jean
A1  - Grandjean, Didier
A1  - Maquet, Pierre
A1  - Schwartz, Sophie
A1  - Dumont, Marie
A1  - Doyon, Julien
A1  - Carrier, Julie
SP  - 954
EP  - 961
VL  - 70
IS  - 10
N2  - BACKGROUND: Vulnerability to the reduction in natural light associated with fall/winter is generally accepted as the main trigger of seasonal affective disorder (SAD), whereas light therapy is a treatment of choice of the disorder. However, the relationship between exposure to light and mood regulation remains unclear. As compared with green light, blue light was shown to acutely modulate emotion brain processing in healthy individuals. Here, we investigated the impact of light on emotion brain processing in patients with SAD and healthy control subjects and its relationship with retinal light sensitivity. METHODS: Fourteen symptomatic untreated patients with SAD (34.5 ± 8.2 years; 9 women) and 16 healthy control subjects (32.3 ± 7.7 years; 11 women) performed an auditory emotional task in functional magnetic resonance imaging during the fall/winter season, while being exposed to alternating blue and green monochromatic light. Scotopic and photopic retinal light sensitivities were then evaluated with electroretinography. RESULTS: Blue light enhanced responses to auditory emotional stimuli in the posterior hypothalamus in patients with SAD, whereas green light decreased these responses. These effects of blue and green light were not observed in healthy control subjects, despite similar retinal sensitivity in SAD and control subjects. CONCLUSIONS: These results point to the posterior hypothalamus as the neurobiological substrate involved in specific aspects of SAD, including a distinctive response to light and altered emotional responses.<p />  <p>Language: en</p>
LA  - en
SN  - 0006-3223
UR  - http://dx.doi.org/10.1016/j.biopsych.2011.06.022
ID  - ref1
ER  -