Although it is evident from numerous studies that patients with mood disorders generally have a deficient social functioning and a weak social network, little is known about these aspects of seasonal affective disorder (SAD) patients. We studied the social situation, the social network and the social functioning of SAD (n = 20) patients in comparison with matched suicide attempters (SA) with non-seasonal major depression, and with findings from other major depressive disorder (MDD) studies and community samples. The social situation and the clinical background of both the SAD and the SA groups were almost similar and the social networks were equally disadvantageous and weaker than those observed in some community/healthy populations. Furthermore, the data on global functioning and social adjustment of the SAD group were well comparable to those of other MDD patients and significantly worse than that of a community sample. Thus, the results indicate a considerable social impairment in SAD.

The present explosive growth of interest in the therapeutic possibilities of exposure to light was triggered by a patient, Herbert Kern. He suffered from episodic depressive and manic complaints and discovered, by registering these over the years, a seasonal pattern in their occurrence. Discussions with scientists of the NIMH resulted in his participation in a bright light-treatment experiment when he was depressed in the winter of 1980-1981. He recovered.

Next, the same group of investigators defined the criteria for a new syndrome, Seasonal Affective Disorder (SAD): a history of major affective disorder (according to the Research Diagnostic Criteria), at least two consecutive years in which the depressions have occurred during fall or winter and remitted in the following spring or summer, and the absence of any clear-cut seasonally changing psychosocial variable, such as work, stress and so on.

The amygdala has a key role in automatic non-conscious processing of emotions. Highly salient emotional stimuli elicit amygdala activity, and happy faces are among the most rapidly perceived facial expressions. In backward masking paradigms, an image is presented briefly and then masked by another stimulus. However, reports of amygdala responses to masked happy faces have been mixed. In the present study, we used functional magnetic resonance imaging (fMRI) to examine amygdala activation to masked happy, sad, and neutral facial expressions. Masked happy faces elicited greater amygdala activation bilaterally as compared to masked sad faces. Our findings indicate that the amygdala is highly responsive to non-consciously perceived happy facial expressions. (JINS, 2010, 16, 383–387.)