Autumn blues? Let the sunshine in falling leaves, flowers, and cold winds. For many people late autumn can be a season of depression. Those who suffer from " the autumn blue" are often extremely tired, lack energy, need more sleep, feel increased appetite and gain weight. "The exact cause of this condition, often called seasonal depression or seasonal affective disorder (SAD), is not known yet," says Chen Jue, associate professor at Shanghai Mental Health Center. "But recent studies indicate that weather change is influential and strongly suggest that this condition is caused by changes in the availability  of sunlight." One theory is that with decreased exposure to sunlight, the biological clock that regulates mood, sleep, and hormones is delayed, running more slowly in winter. Exposure to light may reset the biological clock. Another theory is that brain chemicals that transmit information between nerves, called neurotransmitters (for example, serotonin), may be altered in individuals with SAD. It is believed that exposure to light can correct these imbalances. "It is a sad season, but you can try to make it happy. Remember, spring always lives in your heart," Chen says. "Going outdoors to get some sunlight may reduce the tension that brings you the low spirits. Relax at work. Stretch, breathe deeply. Take a tea break. Think of your next vacation. Color treatment also works in handling low mood. Music also plays a role in treating autumn blues." Which of the following is true according to the text?
The real cause for autumn blues is still unknown. Autumn blues can be feelings of happiness. People feel tired in autumn. Weather doesn't change people.