The present study explored the possible roles of perinatal photoperiod and latitude as predictors of later reaction to chronobiological stress... Show moreThe present study explored the possible roles of perinatal photoperiod and latitude as predictors of later reaction to chronobiological stress, specifically the experience of winter in Chicago (41.89°N). Participants consisted of new undergraduate and graduate students at a technological university in Chicago, Illinois (N = 64 - 76). The sample was 62% male, ranged in age from 18 to 38 years (M = 22.5, SD = 4.3), and was born mainly in North America and East/South Asia. The vegetative and cognitive/affective subscales of the Seasonal Assessment Form (SAF; Young et al., 2012) were completed by participants between February 7 and March 7, 2011. Results indicated that both perinatal photoperiod and latitude have a significant effect on vegetative but not cognitive symptom severity. A curvilinear relationship between perinatal photoperiod and winter vegetative symptom severity was displayed with optimal adjustment (minimum vegetative symptoms) occurring near LD 12:12. Attention should be paid to the stronger effect of latitude at birth over perinatal photoperiod on symptom severity. Implications, limitations, and future directions for research are discussed. M.S. in Psychology, May 2013 Show less
