One of the early signs that may suggest a problem with the brain, such as dementia, may be a disruption in sleep patterns.
The suprachiasmatic nucleus (SCN) in the hypothalamus of the brain is responsible for controlling our sleep-wake patterns. This is often called a circadian rhythm because these patterns tend to persist at a near-day period.
With many types of neurodegenerative diseases -- including dementias such as Alzheimer’s disease, as well as movement disorders such as Parkinson’s disease -- certain areas of the brain may degenerate over time. Brain cells (neurons) may become less responsive to chemicals called neurotransmitters, or debris may build up disrupting their function. Global brain degeneration, called atrophy, may occur as individual neurons die off. In addition, specific regions of the brain may be lost.
If the SCN is lost, our ability to maintain a normal sleep-wake pattern will be adversely affected. This may manifest in various circadian rhythm disorders. Often, the elderly will experience advanced sleep phase syndrome. This involves a desire to go to bed and wake up early. This desire to change their sleep schedule may be beyond their control and could represent changes in the brain as it ages.
