Ascending reticular activating system (ARAS)
The afferent fibers running through the reticular formation that influence physiological arousal.
A hypothetical process involving the gradual conversion of information into durable memory codes stored in long-term memory.
A splitting off of mental processes into two separate, simultaneous streams of awareness.
A device that monitors the electrical activity of the brain over time by means of recording electrodes attached to the surface of the scalp.
The entire family of internally produced chemicals that resemble opiates in structure and effects.
A diverse group of drugs that have powerful effects on mental and emotional functioning, marked most prominently by distortions in sensory and perceptual experience.
Dreams in which people can think clearly about the circumstances of waking life and the fact that they are dreaming, yet they remain asleep in the midst of a vivid dream.
A compound drug related to both amphetamines and hallucinogens, especially mescaline; commonly called "ecstasy."
A family of mental exercises in which a conscious attempt is made to focus attention in a nonanalytical way.
A disease marked by sudden and irresistible onsets of sleep during normal waking periods.
Abrupt awakenings from NREM sleep accompanied by intense autonomic arousal and feelings of panic.
Non-REM (NREM) sleep
Sleep stages 1 through 4, which are marked by an absence of rapid eye movements, relatively little dreaming, and varied EEG activity.
The condition that exists when a person must continue to take a drug to avoid withdrawal illness.
The fact that subjects' expectations can lead them to experience some change even though they receive an empty, fake, or ineffectual treatment.
The condition that exists when a person must continue to take a drug in order to satisfy intense mental and emotional craving for the drug.
A deep stage of sleep marked by rapid eye movements, high-frequency brain waves, and dreaming.
A process in which neurotransmitters are sponged up from the synaptic cleft by the presynaptic membrane.
Sleep-inducing drugs that tend to decrease central nervous system activation and behavioral activity.
A sleep disorder characterized by frequent reflexive gasping for air that awakens a person and disrupts sleep.
Slow-wave sleep (SWS)
Sleep stages 3 and 4, during which low-frequency delta waves become prominent in EEG recordings.