Seasonal affective disorder (SAD), sometimes called seasonal depression, describes depressive episodes that recur at a particular time of year and remit at another time. This lesson introduces its seasonal pattern, common symptoms, relationship to other mood disorders, and diagnostic criteria.
SAD is commonly associated with changes in daylight during winter or summer, although seasonal light changes are not always involved. People generally have typical mental health for much of the year and experience depressive symptoms at a recurring time. The timing, duration, severity, and symptoms vary from person to person.
All flashcards
Seasonal pattern specifier
A diagnostic description of recurring mood episodes at a characteristic time of year; it can apply to recurrent major depression or bipolar disorder.
Winter-pattern SAD
Often involves hypersomnia, difficulty waking, low energy, increased appetite, carbohydrate cravings, or weight gain.
Melatonin and seasonal rhythms
Melatonin is produced by the pineal gland in dim light and darkness; its secretion is shaped by the internal clock and can be suppressed by bright light.
Typical bright-light therapy session
A person commonly sits 30–60 cm from a lightbox for 30–60 minutes, with eyes open but not staring directly at the light.
Vitamin D as a SAD treatment
It may help correct a deficiency, but evidence for vitamin D as a standalone SAD treatment is mixed and inconclusive.
Quiz questions
In current DSM terminology, how is seasonal affective disorder generally represented?Answer: As a course specifier that can accompany recurrent major depression or bipolar disorder.
Which description best matches a typical bright-light therapy session for winter-pattern SAD?Answer: Sitting near a bright lightbox for a scheduled session, often lasting 30–60 minutes.
What conclusion can be drawn from reported associations between ADHD symptoms and seasonal or circadian disturbances?Answer: The findings suggest an association but do not establish that ADHD causes SAD.
Why should reported SAD prevalence estimates from different locations be compared cautiously?Answer: Studies vary in definitions, methods, and the populations they survey.