PSYA01H3 Chapter Notes - Chapter 5: Pineal Gland, Polysomnography, Alpha Waves
Document Summary
Consciousness a person"s subjective experience of the world and mind. Humans and animals have biological rhythms that are adapted to the cycles in the environment: ex: animals hibernating in the winter. Cells in the retina of the eye relay message about light levels in the environment to the scn. The scn, then communicates signals about light levels with the pineal gland. The pineal gland releases a hormone called melatonin, which peaks in concentration at nighttime and is reduced during wakefulness. Light is the primary stimulus regarding the human circadian rhythm. Ex: blind people cannot send light signals from the retina to the scn and pineal gland. Therefore, the circadian rhythms do not synchronize to day-night cycles but can be adjust by using melatonin doses: circadian rhythms change with age. Generally, people will experience a change in when they prefer to sleep. People have high alertness and cognitive functioning during their preferred time of day.
