seasonal affective disorder causes
Seasonal Affective Disorder Causes
Do you have a pattern of mood swings for a particular season? It could be seasonal affective disorder that may be the problem. Is this a psychological or a physical issue? Know its causes and some more detailed information in this article.
- A major cause according to experts is sunlight. The less exposure of sunlight in the fall and winter months make the difference to a person's mood and energy levels. There is a link of the brain being directly responsible. It can be explained in the following.
- The human brain produces two hormones that are responsible for the mood and energy levels, sleep, etc. They are serotonin and melatonin. These hormones are known to be responsible for the sleep patterns and the energy levels in the body. It is believed that the hypothalamus is the point where these hormones are stimulated. Sunlight affects the release of these hormones, and without adequate sunlight the amount of serotonin, melatonin gets imbalanced. It also disturbs the internal clock of the body, which is called the 'circadian rhythm'.
- Serotonin is the hormone that manages the mood factors, appetite and sleep patterns. It is also termed as a feel good hormone, that is responsible for the transmission of signals between the nerves and the brain. This neurotransmitter, when not produced in adequate quantities, due to less sunlight affects the mood of the individual, leading to depression.
- Melatonin is a hormone produced in the pineal glands at night, this is what creates the drowsy feeling as the night progresses. This production is stopped gradually as the sun shines in the morning. This light when enters the eye, signals this gland to stop producing melatonin. But in winter due to longer nights and shorter days, the production of melatonin lessens, as the nights are longer, and sunlight on dull days is not enough to stop the production of this hormone. This eventually leads to the drowsy feeling and tiredness in dull and dark days.
- The circadian rhythm is another factor that is responsible. During the low sunlight days and longer nights, the internal body clock may get imbalanced, as the body is not used to the sunlight pattern and intensity. Most of the time, people may leave for work before dawn, or return home when it already gets dark. This can lead to the disturbance in the normal circadian rhythm, adding to SAD's causes.
- There are other substances as well that affect the brain and mood cycles in the body. Neurotransmitters like acetylcholine and catecholamines, contain adrenaline and dopamine which are affected during SAD. Another neurotransmitter and stress hormone called Corticotropin - releasing factor, is also observed to be interacting with serotonin in the cases of SAD, dealing with depression.
- A genetic link can also be the cause for SAD, so depression can run in the family. People with hereditary depression issues, are more likely to get affected.
- Some other causes like childhood abuse - physical, emotional or isolation, social factors and individual factors - like if you already suffer from anxiety or depression can trigger SAD.