Seasonal Affective Disorder

Individual differences in diurnal preferences and circadian rhythms are viewed as an interesting dimension of human personality. Previous research has examined various psychological correlates of diurnal preference. Evening types reported psychological and psychosomatic disturbances more frequently and intensively than morning types and morning types have a healthier lifestyle than evening types. Depression was also related to eveningness as were bulimic behaviour and seasonal affected disorders (SAD). Given these studies, one would expect a positive relationship between satisfaction with life or happiness (general well-being; Diener et al. (J Pers Assess 49:71–75, 1985)) and morningness. There was a significant positive correlation between morningness and satisfaction with life (r = 0.177; p = 0.023; N = 164).

Light therapy for the treatment of sleep disorders and jet-lag, as well as for seasonal affective disorder (SAD) has been shown to be effective for many subjects. However, concerns are sometimes expressed about the safety of viewing relatively bright light boxes used in this type of light phototherapy treatment. Typically, a patient is illuminated—normally not on-axis—by an illuminance of approximately 2,500 lux to 10,000 lux as measured at the corneal plane of the eye for periods ranging up to two hours, or even longer each day. Normally there is little ultraviolet radiation from either fluorescent or LED-array light sources. The greatest concerns have centered on the potential retinal hazard from the "blue-light hazard," as described in photobiological lamp safety standards. Currently evaluated, diffused sources do not pose a hazard.

Suicidal behavior and mood disorders are one of the world’s largest public health problems. The biological vulnerability for these problems includes genetic factors involved in the regulation of the serotonergic system and stress system. The hypothalamic-pituitary-adrenal (HPA) axis is a neuroendocrine system that regulates the body’s response to stress and has complex interactions with brain serotonergic, noradrenergic and dopaminergic systems. Corticotropin-releasing hormone and vasopressin act synergistically to stimulate the secretion of ACTH that stimulates the biosynthesis of corticosteroids such as cortisol from cholesterol. Cortisol is a major stress hormone and has effects on many tissues, including on mineralocorticoid receptors and glucocorticoid receptors in the brain. Glucocorticoids produce behavioral changes, and one important target of glucocorticoids is the hypothalamus, which is a major controlling center of the HPA axis. Stress plays a major role in the various pathophysiological processes associated with mood disorders and suicidal behavior. Serotonergic dysfunction is a well-established substrate for mood disorders and suicidal behavior. Corticosteroids may play an important role in the relationship between stress, mood changes and perhaps suicidal behavior by interacting with 5-HT1A receptors. Abnormalities in the HPA axis in response to increased levels of stress are found to be associated with a dysregulation in the serotonergic system, both in subjects with mood disorders and those who engage in suicidal behavior. HPA over-activity may be a good predictor of mood disorders and perhaps suicidal behavior via abnormalities in the serotonergic system.

Melatonin (N-acetyl-5-methoxytryptamine) was first purified and characterized from the bovine pineal gland extract by Aron Lerner and co-workers in 1958. Since then, a plethora of information has piled up on its biosynthesis, metabolism, time-bound periodicity, physiological and patho-physiological functions, as well as its interactions with other endocrine or neuro-endocrine organs and tissues in the body. Melatonin has wide range of applications in physiology and biomedical fields. In recent years, a significant progress has been made in the understanding mechanism of its actions at the cellular and molecular levels. Consistent efforts have uncovered the mystery of this indoleamine, and demonstrated its role in regulation of a large as well as diverse body functions in different groups of animals in general, and in humans in particular. Current review, in commemoration of 50 years of discovery of melatonin, while revisiting the established dogmas, summarizes current information on...

The study aimed to elucidate previously observed associations between morningness-eveningness and seasonality by analysing their distinct aspects separately: morning affect (MA) and time-of-day preference, different seasonal types and patterns (winter, summer, etc.), the degree of seasonality and perceived negative impact of seasonality. Students from Warsaw (N=522) completed the Seasonal Pattern Assessment Questionnaire (SPAQ) and the Composite Scale of Morningness. Winter seasonality was related to lower MA, but unrelated to time-of-day preference. Global seasonality score (GSS) was negatively associated with MA in winter seasonality, but not in other seasonality patterns, and unrelated to time-of-day preference. These associations remained significant after controlling for sex, age, and season of assessment. It is concluded that winter seasonality is related to low MA, but not to time-of-day preference. The above results indicate that MA can be considered as an all year round indicator of proneness to winter seasonality and eventually to SAD. The results also suggest that MA and time-of-day preference should be analysed separately in future research on morningness-eveningness.

BackgroundA large number of psychiatric disorders are more present in women more than in men. Among these, there are major depression (twice as frequent in women compared to men), unipolar depression, and seasonal affective disorder. On the other hand, dysthymia and bipolar disorder have similar frequencies in men and women, but they have a different representation of symptomatology.

This dissertation investigates agency of character and environment in Scandinavian crime fiction. Close reading of Miss Smilla’s Feeling for Snow (Høeg, 1992), The Ice Princess (Lackberg, 2003), and Snow Angels (Thompson, 2010) shows that environment contains an unexpected level of agency in murder. My framework is influenced by theories of Seasonal Affective Disorder (SAD) and psychology. My work therefore reveals a link between the agency of environment and the Nordic setting.

Mood spectrum disorders (bipolar disorder, recurrent depressive disorder and seasonal affective disorder) are accompanied by circadian deregulations, which can occur during acute mood episodes as well as during euthymic periods, and are particularly common among bipolar patients in remission. This suggests that altered circadian rhythms may be biological markers of these disorders. Rhythm dysfunctions have been observed in mood disorder patients by using actigraphic measures and by assessing social metric rhythms, diurnal preferences and melatonin secretion. Since many of these markers are heritable and therefore driven by clock genes, these genes may represent susceptibility factors for mood spectrum disorders. Indeed, several genetic association studies have suggested that certain circadian gene variants play a role in susceptibility to these disorders. Such connections to circadian genes such as CLOCK, ARNTL1, NPAS2, PER3 and NR1D1 have been repeatedly demonstrated for bipolar di...