Summarize

Some people in northern country suffer Seasonal Affective Disorder (SAD) in winter. Sufferers are getting more depressed as the day become shorter. This condition happens to Janet Blake who works as public relation officer. While night became longer, she was very stressful and involved making speeches and appearing on television and radio. Dr. Hamish MacRae, who has made a special study of SAD, treats her by installing a special lightbox in Janet's house which simulates sunlight. This lightbox can help to keep behaviour of SAD sufferers in balance.