Seasonal Affective Disorder: Illuminating the Latitude Hypothesis
Open Access
Author:
Graceffo, James Michael
Graduate Program:
Counseling Psychology
Degree:
Doctor of Philosophy
Document Type:
Dissertation
Date of Defense:
August 21, 2015
Committee Members:
Jeffrey Hayes, Dissertation Advisor/Co-Advisor Kathleen Bieschke, Committee Member Louis Georges Castonguay, Committee Member Eugene Edmund Clothiaux, Committee Member
Keywords:
Seasonal Affective Disorder College Students Depression
Abstract:
The present study investigated the relationship between meteorological variables and depressive symptoms. More specifically, we explored the effects of time of year (hours of daylight, or photoperiod, will serve as a proxy measure for time of year) and cloud cover (irradiance measures from surface radiation budget sites across the United States) on depression scores in both treatment and non-treatment seeking samples of college students. Previous research into the latitude gradient has neglected important environmental factors that can influence the level of light a person experiences day-to-day. We hypothesized that time of year and cloud cover would be inversely related to depression scores. The results failed to support the hypotheses, which is later discussed in greater detail.