@article{ref1,
title="Seasonal changes in mood and behavior. The role of genetic factors",
journal="Archives of general psychiatry",
year="1996",
author="Madden, Pamela A. F. and Heath, Andrew C. and Rosenthal, Norman E. and Martin, N. G.",
volume="53",
number="1",
pages="47-55",
abstract="BACKGROUND: Seasonal rhythms in mood and behavior (seasonality) have been reported to occur in the general population. Seasonal affective disorder, a clinically diagnosed syndrome, is believed to represent the morbid extreme of a spectrum of seasonality. Two types of seasonality have been clinically described: one characterized by a winter pattern and a second by a summer pattern of depressive mood disturbance. METHODS: By using methods of univariate and multivariate genetic analysis, we examined the relative contribution of genetic and environmental factors to the risk of seasonality symptoms that were assessed by a mailed questionnaire of 4639 adult twins from a volunteer-based registry in Australia. RESULTS: Seasonality was associated with a winter rather than a summer pattern of mood and behavioral change. In each behavioral domain (ie, mood, energy, social activity, sleep, appetite, and weight), a significant genetic influence on the reporting of seasonal changes was found. Consistent with the hypothesis of a seasonal syndrome, genetic effects were found to exert a global influence across all behavioral changes, accounting for at least 29% of the variance in seasonality in men and women. CONCLUSIONS: There is a tendency for seasonal changes in mood and behavior to run in families, especially seasonality of the winter type, and this is largely due to a biological predisposition. These findings support continuing efforts to understand the role of seasonality in the development of mood disorders.<p /><p>Language: en</p>",
language="en",
issn="0003-990X",
doi="",
url="http://dx.doi.org/"
}