Bright Light: A Novel Treatment for Anxiety

The primary aim of this research was to examine the influence of bright light on anxiety in high-anxious young adults. In an acute exposure study, participants were randomly assigned to 45 min of either (1) bright light (3,000 lux) or (2) a placebo inactivated negative ion generator. Treatments were initiated ≤1 hr after awakening. At 10 min before and 30 min after the treatments, state anxiety, mood, and blood pressure were assessed. Following the acute exposure study, participants performed a 5-week study. Following a a 1-week baseline, participants were randomly assigned to four weeks of daily exposure to either (1) bright light (45 min/day; 3,000 lux) or (2) placebo inactivated negative ion generator, which were initiated ≤1 hr after awakening. Before and after the experiment, clinical ratings were conducted with the Hamilton Anxiety Scale, the Hamilton Depression Scale, and the Clinical Global Impressions scale (CGI). Following baseline, and following each week of treatment, blood pressure, as well as questionnaires for state anxiety, depression, mood, sleep, and side effects were assessed.

1 week period, in which subjects followed usual schedule, though they were asked to maintain a fairly stable sleep schedule. The baseline period was used for comparison with the experimental intervention.

Four weeks of daily exposure to bright light (3,000 lux) for 45 min/day, beginning within 60 min of arising.

Four weeks of daily exposure to inactivated negative ion generator for 45 min/day, beginning within 60 min of arising

Inclusion Criteria: Having a level of trait anxiety [Spielberger State-Trait Anxiety Inventory (Form Y1)]{23642} that was ≥ the 75th percentile for their age (i.e., ≥ 46 and ≥ 44 for women and men, respectively) Exclusion Criteria: Current treatment for anxiety or depression; History of bipolar disorder, mania, or psychotic disorders; History of winter depression, which might bias towards positive response to light; Hypertension; Ophthalmic abnormalities; and Usual exposure to high levels of light such that the intervention would add little to usual exposure.

Youngstedt SD, Kline CE, Ginsberg JP, Zielinski MR, Hardin JW. Bright light treatment for high-anxious young adults: a randomized controlled pilot study. Depress Anxiety. 2011 Apr;28(4):324-32. doi: 10.1002/da.20784. Epub 2011 Jan 19.