The main purpose of these studies is to explore the mechanism(s) by which bright light exerts an antidepressant effect in patients with winter seasonal affective disorder (SAD). It has been difficult to rule out a placebo effect because of the difficulty in designing an adequate placebo control. There are several problems with the use of dim light, the most commonly used placebo, primarily that patients usually expect greater benefit from bright light. To avoid this problem we have developed an unique 'environmental' placebo. Patients will be tested in five-week parallel groups design with three groups, morning light, evening light and placebo. Thus we will be able to compare the antidepressant effect of morning light vs. evening light, morning light vs. placebo, and evening light vs. placebo. We will also evaluate the phase-shift theory that the antidepressant mechanism of bright light is due to shifting circadian rhythms. Half of the SAD subjects in each of the three groups will have their circadian rhythm of body temperature continuously measured for the five weeks. Age and sex matched normals will serve as controls. We will also study a group of subjects who have the core symptoms of SAD, decreased energy, increased sleep, and increased appetite, but who do not meet criteria for major depression. A similar sample has been termed subsyndromal SAD. Epidemiological studies suggest that a large group of people in temperate latitudes fall into this category. We will study their response to bright light with the same design mentioned above. As a further means of exploring mechanisms the fall onset and spring offset of the various symptoms will be charted over two years to determine sequence and to document the seasonal nature of the syndrome.

Agency
National Institute of Health (NIH)
Institute
National Institute of Mental Health (NIMH)
Type
Research Project (R01)
Project #
5R01MH042768-05
Application #
3382024
Study Section
Psychopathology and Clinical Biology Research Review Committee (PCB)
Project Start
1987-09-30
Project End
1993-11-30
Budget Start
1992-02-01
Budget End
1992-11-30
Support Year
5
Fiscal Year
1992
Total Cost
Indirect Cost
Name
Rush University Medical Center
Department
Type
DUNS #
City
Chicago
State
IL
Country
United States
Zip Code
60612
Burgess, Helen J; Fogg, Louis F; Young, Michael A et al. (2004) Bright light therapy for winter depression--is phase advancing beneficial? Chronobiol Int 21:759-75
Eastman, C I; Young, M A; Fogg, L F et al. (1998) Bright light treatment of winter depression: a placebo-controlled trial. Arch Gen Psychiatry 55:883-9
Young, M A; Meaden, P M; Fogg, L F et al. (1997) Which environmental variables are related to the onset of seasonal affective disorder? J Abnorm Psychol 106:554-62
Eastman, C I; Gallo, L C; Lahmeyer, H W et al. (1993) The circadian rhythm of temperature during light treatment for winter depression. Biol Psychiatry 34:210-20
Eastman, C I; Lahmeyer, H W; Watell, L G et al. (1992) A placebo-controlled trial of light treatment for winter depression. J Affect Disord 26:211-21
Young, M A; Watel, L G; Lahmeyer, H W et al. (1991) The temporal onset of individual symptoms in winter depression: differentiating underlying mechanisms. J Affect Disord 22:191-7
Eastman, C I (1990) Natural summer and winter sunlight exposure patterns in seasonal affective disorder. Physiol Behav 48:611-6
Eastman, C I (1990) What the placebo literature can tell us about light therapy for SAD. Psychopharmacol Bull 26:495-504