Seasonal Affective Disorder : A type of depression that follows a seasonal pattern, most commonly starting in the late fall or winter and going away in the spring.
Causes:
Doctors believe SAD is linked to changes in sunlight and your body's internal balance:
- Circadian Rhythm: Shorter winter days can disrupt your body's internal clock.
- Melatonin Levels: Less sunlight can cause your body to produce too much melatonin, a hormone that makes you sleepy.
- Serotonin Levels: Reduced sunlight can lower serotonin, a brain chemical that helps regulate mood.
What does this have to do with this guy?
Well...
Winter Whites experience significant biological and behavioral changes during short winter days.
How?
- Coat Color Changes: their dark fur turns to white or greyish-white (hence the name "winter white").
- Hormones and Metabolism: Reduced light levels alter their body weight, testosterone levels, and hormone production.
- Melatonin Shifts: Longer nights cause extended periods of nightly melatonin secretion, mirroring the hormonal shifts linked to winter blues in humans.
This roughly mimics the significant biological and behavioral changes that humans facing seasonal affective disorder experience.
The Ohio State University
Has performed studies that show that hamsters housed in short-stay, low-light conditions exhibit increased anxiety-like and depressive-like behaviors compared to those in long-day settings.
Because their brain chemistry reacts strongly to changing light cycles, scientist use Winter White hamsters to research circadian rhythms and test potential light therapies.