The name is absent

childhood, adolescence, adulthood, and into old age” (Carskadon & Dement, 2005, p.
13).

The pupils of the eyes generally appear constricted during REM sleep (Siegel,
2005), but they presumably dilate initially and do so periodically throughout this stage of
the sleep cycle (Rechtschaffen, 1998). The heart rate periodically decelerates (Taylor,
Moldofsky, & Furedy, 1985; Verrier, Harper, & Hobson, 2005; Verrier et al., 1998).
REM sleep has been described as “activated” or “paradoxical” sleep because the brain
appears active, and the EEG becomes desynchronized in a manner that resembles
wakefulness (Siegel, 2005). It is also possible to observe rhythmic theta waves (Lerma &
Garcia-Austt, 1985; Rowe et al., 1999; Sakai, Sano, & Iwahara, 1973; Sei & Morita,
1996), which are closely associated with activity in the hippocampus (Green & Arduini,
1954; Jung & Kornmueller, 1938; Walter & Walter, 1953; Winson, 1975). These are the
tonic physiological features of REM sleep.

Each period of REM sleep is interrupted several times by phasic bursts of rapid
eye movement (Aserinsky, 1965). In humans, a heart rate deceleration occurs about three
seconds before each eye burst (Taylor, Moldofsky, & Furedy, 1985; Verrier, Harper, &
Hobson, 2005). As eye activity begins, the heart rate surges, arterial blood pressure
increases, and then the heart rate abruptly decelerates (Verrier et al., 2005). The pupils
dilate (Kemp & Kaada, 1975; Rechtschaffen, 1998), the eyes jerk frantically back and
forth (Aserinsky & Kleitman, 1953), and then the pupils constrict (Rechtschaffen, 1998;
Siegel, 2005). Respiratory activity fluctuates (Aserinsky, 1965; Aserinsky & Kleitman,
1953; Sullivan, 1980), and electrodermal activity momentarily increases (Broughton,
Poire, & Tassinari, 1965; Kushniruk, Rustenburg, & Ogilvie, 1985). Cerebral blood flow

preliminary draft (9/24/2006)

<<   1   2   3   4   5   6   >>

More intriguing information