Sleep patterns in the "locked-in" syndrome.

Sleep patterns in two chronically "locked-in" patients were studied. The first patient had sleep activity similar to other quadriparetic patients with reduced physical activity. The second patient experienced no REM sleep and only short bursts of non-REM sleep. Clinical evidence suggested extension of his lesion dorsally into the pontine tegmentum. This correlates well with experimental evidence indicating that structures in the tegmental area are essential for normal sleep.