Sleep

Beta

FIRST STAGE - Awake

Alpha

SECOND STAGE - Brain waves are relatively still, very low frequency

Theta

THIRD STAGE - Contains sleep spindles and K-complex; both are acceleration in neural activity, however K-complex is a much greater burst

Delta

FOURTH STAGE - Deep sleep; rapidly changing frequency in brain waves, mostly high

REM

Important for memories and the point where dreams occur; similar wave frequency to Alpha

Paradoxical state

A point where the mind is awake but the body is not (ex. Sleep paralysis)

Circadian rhythm

24-hour sleep cycle; affected by light and jet lag

Manifest content

Actual dream: what happened in the dream?

Latent

The meaning behind the dream

Activation synthesis dream theory

The belief that dreams happen due to neuron activity; there is no real meaning to dreams

Apnea

Difficulty/no breathing when sleeping

Central apnea

Brain is not sending “breathing” signals

Obstructive apnea

Something is blocking the persons ability to breathe during sleep

Narcolepsy

Inability to stay awake