Directions Unit- Research into SAD

Research into SAD, the disorder my character James has. 
Seasonal affective disorder (SAD) is a type of depression that has a seasonal pattern. The episodes of depression tend to occur at the same time each year, usually during the winter.
As with other types of depression, two of the main symptoms of SAD are a low mood and a lack of interest in life. Other symptoms of SAD include:
being less active than normal 
sleeping more
Read more information about the symptoms of seasonal affective disorder. 
Winter depression
SAD is sometimes known as "winter depression" because the symptoms are more apparent and tend to be more severe at this time of the year.
The symptoms often begin in the autumn as the days start getting shorter. They are most severe during December, January and February.
In most cases, the symptoms of SAD begin to improve in the spring before disappearing.
What causes SAD?
The exact cause of SAD is not fully understood, but it is thought to be linked to reduced exposure to sunlight during the shorter days of the year.
Sunlight can affect some of the brain's chemicals and hormones. However, it is not clear what this effect is. One theory is that light stimulates a part of the brain called the hypothalamus which controls mood, appetite and sleep. These things can affect how you feel.
In people with SAD, a lack of sunlight and a problem with certain brain chemicals stops the hypothalamus working properly. The lack of light is thought to affect:
the production of the hormone melatonin
the production of the hormone serotonin
the body's circadian rhythm (the body's internal clock, which regulates several biological processes during a 24-hour period)

For more information:


http://www.nhs.uk/conditions/Seasonal-affective-disorder/Pages/Introduction.aspx