Final answer:
Bright light therapy is used to treat Seasonal Affective Disorder (SAD) by regulating melatonin production and adjusting circadian rhythms, especially during months with limited natural light.
Step-by-step explanation:
Specialized bright light therapy may help patients suffering from Seasonal Affective Disorder (SAD). SAD is a mood disorder where symptoms such as increased appetite, sluggishness, and increased sleepiness primarily occur during the winter months due to shorter daylight hours. Melatonin, a hormone that regulates sleep-wake cycles, plays a role in SAD, as its production is influenced by light exposure. During long winter nights, increased melatonin can disrupt circadian rhythms, contributing to the symptoms of SAD. As a non-drug therapy, bright light therapy works by providing exposure to artificial bright light which helps to regulate melatonin production, realign circadian rhythms, and alleviate symptoms of SAD