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Background: Despite evidence that bright light can improve mood, the neurobiology remains poorly understood. Some evidence implicates the catecholamines. In the present study, we measured the effects of transiently decreasing dopamine (DA) synthesis on mood and motivational states in healthy women with mild seasonal mood changes who were tested in either bright or dim light. Methods: On 2 test days, participants slept overnight in a light-controlled room. On the morning of each session, half of the participants awoke to gradual increases of bright light, up to 3000 lux, and half to dim light (10 lux). For all participants, DA was reduced on 1 of the test days using the acute phenylalanine/tyrosine depletion (APTD) method; on the other day, they ingested a nutritionally balanced control mixture (BAL). Beginning 4 hours postingestion, participants completed subjective mood questionnaires, psychological tests and a progressive ratio breakpoint task during which they worked for successive units of $5. Results: Thirty-two women participated in our study. The APTD lowered mood, agreeableness, energy and the willingness to work for monetary reward. The effects on energy and motivation were independent of light, while the effects on mood and agreeableness were seen in the dim condition only, being prevented by bright light. Limitations: Acute phenylalanine/tyrosine depletion might affect systems other than DA. The sample size was small. Conclusion: These results suggest that increased DA function may be responsible for some of the beneficial effects of light, while adding to the evidence that the neurobiology of mood and motivational states can be dissociated., Introduction Bright light can alleviate low mood in patients with seasonal affective disorder (SAD), (1) nonseasonal major depressive disorder, (2,3) antepartum depression, (4) eating disorders (5,6) and those with subsyndromal [...]

Objective: To describe the demographic characteristics of patients who present to the emergency department (ED) for low-acuity issues and to explore their self-reported contact with other sources of primary health care before presenting to the ED., Design: Survey distributed in the ED waiting room., Setting: A high-volume ED in Vancouver, BC., Participants: A total of 232 respondents aged 18 years or older in the ED waiting room., Main Outcome Measures: Actions taken to seek health care for the current issue before presenting to the ED and predictors of first seeking nonurgent care., Results: Of the 398 people approached, 232 (58.3%) people completed the survey. Exactly half (95% CI 43.6% to 56.4%) sought alternative care before presenting to the ED. Predictors for having sought alternative care included illness presentation and longer symptom duration, while injury presentation and work-related presentation were associated with not seeking alternative care. Most participants (162 patients, 87.6%) believed that the ED was the most appropriate place for them to receive care for their problem, while only 87 (45.3%) believed that an adjacent primary care clinic would be an acceptable alternative., Conclusion: Many patients do attempt to seek alternative care before presenting to the ED with low acuity issues. Most patients believe that the ED is the best place for them to receive care and are uncertain about using a primary care alternative. Further research is needed to explore barriers and motivators patients face in their decisions to seek care, as well as potential patient education methods to improve appropriate ED use., (Copyright© the College of Family Physicians of Canada.)