SCIENCE REPORT - Seasonal Affective Disorder

SCIENCE REPORT
–
January 3, 2002: Seasonal¹ Affective Disorder²

By George Grow

This is the VOA Special English SCIENCE REPORT.

Some people feel sad or depressed³ during the winter months in northern areas of the world. They may have
trouble eating or sleeping. They suffer from a condition known as Seasonal Affective Disorder, or S-A-D.

Victims of S-A-D suffer its effects during the short, dark days of winter. The problems are most severe in the
months when there are fewer hours of daylight. When spring arrives, these signs disappear and S-A-D victims
feel well again.

The National Mental Health Association reports that S-A-D can affect anyone. The group says young people and
women are at the highest risk for the disorder. It says that an estimated twenty -five percent of the American
population suffers from some form of S-A-D. About five percent suffer from a severe form of the disorder. Many
people in other parts of the world also have the condition.

For example, some scientists who work in Antarctica suffer from Seasonal Affective Disorder. During the long,
dark winter months there, workers have difficulty finding enough energy to do their jobs.

The idea of health problems linked to a lack of light is not new. Scientists have discussed the issue since the
beginning of medicine. More than two-thousand years ago, the Greek doctor Hippocrates noted⁴ that the seasons
affect human emotions.

Today, experts do not fully⁵ understand S-A-D. Yet they agree that it is a very real disorder. Many doctors think
that a change in brain chemistry causes people to develop S-A-D. They say people with the condition have too
much of the hormone⁶ melatonin in their bodies.

The pineal gland⁷ in the brain produces melatonin while we sleep. This hormone is believed to cause signs of
depression. Melatonin is produced at increased levels in the dark. So, its production increases when the days are
shorter and darker.

To treat the disorder, victims of S-A-D do not need to wait until spring. Experts know that placing affected⁸
individuals in bright light each day eases the condition. There are other things people can do to ease the problem.
They can increase the sunlight in their homes and workplaces. They can spend more time outdoors in the fresh air
during the day.

One study found that walking for an hour in winter sunlight was as effective as spending two-and-one-half hours
under bright light indoors.

This VOA Special English SCIENCE REPORT was written by George Grow.

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1 seasonal   

adj.季节的，季节性的

参考例句：

• The town relies on the seasonal tourist industry for jobs.这个城镇依靠季节性旅游业提供就业机会。
• The hors d'oeuvre is seasonal vegetables.餐前小吃是应时蔬菜。

2 disorder   

n.紊乱，混乱；骚动，骚乱；疾病，失调

参考例句：

• When returning back,he discovered the room to be in disorder.回家后，他发现屋子里乱七八糟。
• It contained a vast number of letters in great disorder.里面七零八落地装着许多信件。

3 depressed   

adj.沮丧的，抑郁的，不景气的，萧条的

参考例句：

• When he was depressed,he felt utterly divorced from reality.他心情沮丧时就感到完全脱离了现实。
• His mother was depressed by the sad news.这个坏消息使他的母亲意志消沉。

4 noted   

adj.著名的，知名的

参考例句：

• The local hotel is noted for its good table.当地的那家酒店以餐食精美而著称。
• Jim is noted for arriving late for work.吉姆上班迟到出了名。

5 fully   

adv.完全地，全部地，彻底地；充分地

参考例句：

• The doctor asked me to breathe in,then to breathe out fully.医生让我先吸气，然后全部呼出。
• They soon became fully integrated into the local community.他们很快就完全融入了当地人的圈子。

6 hormone   

n.荷尔蒙，激素，内分泌

参考例句：

• Hormone implants are used as growth boosters.激素植入物被用作生长辅助剂。
• This hormone interacts closely with other hormones in the body.这种荷尔蒙与体內其他荷尔蒙紧密地相互作用。

7 gland   

n.腺体，(机)密封压盖，填料盖

参考例句：

• This is a snake's poison gland.这就是蛇的毒腺。
• Her mother has an underactive adrenal gland.她的母亲肾上腺机能不全。

8 affected   

adj.不自然的，假装的

参考例句：

• She showed an affected interest in our subject.她假装对我们的课题感到兴趣。
• His manners are affected.他的态度不自然。