Monday, 7 May 2012
Insomnia as a Treatment for Depression
Lack of sleep has a beneficial effect on depression. However counterintuitive this finding may seem, it has been well documented in more than 75 studies published over the past 40 years. One of the reasons that sleep deprivation is not used more extensively in the treatment of depression is that prolonged insomnia can also have significant negative effects on cognitive functioning. Another reason is that insomnia-induced improvements in mood dissipate rapidly when the individuals eventually and inevitably catch up on their sleep.
Nevertheless, the antidepressant effect of insomnia is so robust, takes hold so quickly, and offers so much promise that many studies on it are now in progress.
Some of these studies seem to indicate that the activity of a particular brain structure, the anterior cingulate cortex, which is higher than normal in depressed people, becomes calmer after a period of insomnia.
Other studies have been inspired by the observation that one category of medications used to treat depression—tricyclic antidepressants—have the side effect of disturbing REM sleep. Researchers are investigating whether insomnia may produce its antidepressant effect in the same way, by reducing the length of the REM part of the sleep cycle. Genetic data tend to support this hypothesis: the risks of depression are greater in families with the rare genetic trait of experiencing much more REM sleep than normal.