YOU KNOW YOU ARE READY FOR THE TEST IF YOU ARE ABLE TO…
• Define consciousness and discuss the different levels of consciousness.
• Explain the factors that control sleep, theories on the purpose of sleep, the stages of sleep, and
disorders of sleep.
• Introduce the concept of cognition, as it relates to mental images, concepts and problem
• Explain the basis of language and the relationship between language and thought processes.
is defined as a person’s awareness of the world around him or her.
is defined as the state of awareness where our thoughts and feelings are clear
Altered states of consciousness
describe a shift in the quality or pattern of a
awareness. Examples of altered states of consciousness include using drugs, daydreaming,
being hypnotized, or simply sleeping.
The sleep-wake cycle is a
, meaning one cycle takes about a day to complete.
Based on brain wave activity recorded with the use of an EEG, sleep has been divided into two
rapid eye movement (REM) sleep
. Non-REM sleep is a
deep, restful sleep and consists of four stages. Stage 1 sleep is also called light sleep and
occurs when brain activity begins to shift from
activity. Many people
experience a hypnic jerk in this stage when their body jerks suddenly and wakes them up. As
body temperature continues to drop and heart rate slows, sleep spindles begin to appear on the
EEG recording, signaling Stage 2 of non-REM sleep. Stage 3
occurs when the slow, large
first appear; and when delta waves account for more
than 5percent of the total brain activity, the person is said to be in Stage 4, the deepest stage of
After a person cycles through Stages 1-4 and back, instead of entering Stage 1, people
experience REM sleep. During this type of sleep, the brain is active and displays beta wave
activity, the eye exhibits rapid movements, and the skeletal muscles of the body are temporarily
paralysis is referred to as
. When a person is wakened from this type of sleep
they often report being in a dream state. Most likely, around 90 percent of dreams take place in
although dreams also do occur in non-REM sleep. Contrary to popular belief, people do not go
crazy when deprived of REM sleep; however, they do spend longer amounts of time in REM sleep
when allowed to sleep normally again. This phenomenon is known as