Seasonal Affective Disorder
and the use of light therapy
How seasonal affective disorder can be helped with the use light therapy. This report will be using five studies dating back to nineteen ninety-one.
Seasonal affective disorder as described by Rosenthal and others in nineteen eighty four, is a disorder characterized with recurrent wintertime depression and summer remissions. Light therapy consists of daily exposure to intense bright light. For people affected with seasonal affective disorder they have supersensitivity and subsensitivity to light (Lam, 1991, pp. 1526-1529). One reported study concerning the threshold of adaptation to dark shows that people with seasonal affective disorder are more sensitive to light perception. The adaption to dark threshold test is a psychophysical test that involves a subjective response to determine threshold light perception (Lam, 1991, pp. 1526-1529).
Electrooculography an objective electropsychological test and retinal function (Lam, 1991, pp. 1526-1529). This test measures the standing electrical potential across the eye during eye movements (Lam, 1991, pp. 1526-1529).EOG studies in depression have shown conflicting results. One of the early studies found abnormalities in affective disorder of unspecified seasonality (Lam, 1991, pp. 1526-1529).
A study done with the approval from the University of British Columbia. The subjects from the seasonal mood clinic at the University Hospital (Lam, 1991, pp. 1526-1529).Comparison subjects were recruited by advertisement and match to patients by sex and age (Lam, 1991, pp. 1526-1529). Patients and comparison subjects were interviewed by a psychiatrist, using the Hamilton Depression rating scale, seasonal affective disorder version (Lam, 1991, pp. 1526-1529). The interview guide is composed of a 21 item Hamilton rating scale for depression with an eight item addendum that rates atypical symptoms (Lam, 1991, pp. 1526-1529).
The EOG ratio is...