Brain correlates of SAD have been studied to a small extent so far, but in related disorders such as depression a commonly reported finding is asymmetric activity in frontal brain areas as detected with an electroencephalogram (EEG) [11; 12]. In particular, frontal alpha asymmetry is frequently reported as an EEG biomarker for depression [13; 14; 15; 16; 17]. In patients with depression, brain activity along the anterior-posterior axis and right lateralized resting alpha is subject to change, resulting in dysfunction of the right hemisphere [18]. However, there seems to be inconsistency between studies and several of them have fallen short in finding the effect of atypical frontal alpha asymmetry in depressed patients [18; 19; 20]. Experimental results on SAD and EEG power confirm the physiological similarity between depression and SAD; specifically, asymmetrical distribution as well as lower power for individuals with SAD was reported for most frequency bands as compared to controls [21]. In a recent study, we could demonstrate increased responsivity of the alpha frequency range to sad mood induction among individuals with seasonality symptoms even in the season where these individuals should feel better, i.e., during summer [22]. There is a plausible explanation for the frontal lobe and particularly alpha activity to be abnormal in affective disorders. Specifically, there is a link to memory and emotion, which emerges as frontal asymmetry being indicative of variability in emotional processing [23; 24; 25; 26]. Humans have the tendency to incorporate negative information when learning how to handle situations that require cognitive abilities; the literature suggests that this negativity bias serves an evolutionary purpose [27]. While the grounds for learning from negative affect may be vital in many situations, weighing negative information heavily and dominantly over positive information is a possible indicator of mental disorder [28; 29]. Emotions play a key role in memory consolidation; they induce capturing of attention and increase processing of information [30; 31]. Frontal EEG alpha asymmetry might serve as a mediator for interindividual differences and disease, as it is said to reflect an individual's sensitivity to negative emotional cues [32]. Emotions also seem to be more important for top-down attention in processing stimuli that provoke a sad mood in people with depression [33; 34; 35]. In addition to the alpha band being involved in emotional processing and serving as markers for depressive disorders, gamma oscillations have been consistently reported to be linked to depression [36]. EEG research on emotional memory has led to the conclusion that affective stimuli evoke increased gamma oscillations (35-120 Hz) in the neocortex and the amygdala, particularly stimuli with negative valence [37]. Negative stimuli may undergo enhanced processing, which was suggested to be reflected by responses after 300 ms in the gamma band [38], and this enhanced processing is even more sustained in individuals with depression [39]. These results were interpreted such that neural connectivity and activation of the visual cortex enhance the ability to perceive emotional stimuli early to facilitate fast reaction to what might appear as aversive [38]. An increase in gamma-band event-related synchronization was linked to conscious experience (supraliminal priming) for emotional stimuli [40]. Another study examined event-related gamma rhythm modulation and the phase of synchronization to describe differences in emotional memory by viewing positive, negative, and neutral pictures [41]. Differences in gamma synchronization were found between neutral stimuli and negative stimuli in the gamma range of 38-45 Hz at 0-250 ms post-stimulus [41]. Neuronal activity in the gamma band is also enhanced while processing fearful-looking faces [42]. In line with these findings, an increase in gamma-band power was reported in the right frontal region for positive stimuli and in the left frontal and temporal regions for negative stimuli [43].