7. Circadian Rhythm Sleep-Wake Disorders
are issues that develop when the internal clock in your body—which alerts you when it’s time to sleep or wake—is out of sync with the outside world. Your circadian clock repeats itself about every 24 hours. People with Alzheimer’s disease, Parkinson’s disease, and patients who have experienced head trauma may have circadian rhythm sleep disorders.
8. Non–Rapid Eye Movement Sleep Arousal Disorders
The most frequent incidents of incomplete waking from sleep are caused by non-rapid eye movement (NREM) sleep arousal disorders, which can also occasionally involve more complicated actions. These events often occur in the first third of the night, and in the morning, people have no recollection of the incidents. The most frequent age group for NREM sleep arousal problems is childhood, followed by ageing.