Central Nervous System: The brain and spinal cord.
Cerebral cortex: The region of the brain responsible for cognitive functions including reasoning, mood, and perception of stimuli.
Dissociative: a type of compound, such as phencyclidine or ketamine, that produces an anesthetic effect characterized by a feeling of being detached from the physical self.
DXM: A common street name for dextromethorphan.
Flashback: A sudden but temporary recurrence of aspects of a drug experience (including sights, sounds, and feelings) that may occur days, weeks, or even more than a year after hallucinogenic drug use.
Glutamate: An excitatory neurotransmitter found throughout the brain that influences the reward system and is involved in learning and memory, among other functions.
Hallucinogen: A drug that produces hallucinations—distortions in perception of sights and sounds—and disturbances in emotion, judgment, and memory.
HPPD: Hallucinogen persisting perception disorder; the spontaneous and sometimes continuous recurrence of perceptual effects of LSD long after an individual has ingested the drug.
Kappa opioid receptor: A receptor on nerve cells that is activated by certain opioid-like compounds produced in the body. These receptors differ from those activated by the more commonly known opioids, such as heroin and morphine.
Neurotransmitter: A chemical compound that acts as a messenger to carry signals from one nerve cell to another.
NMDA receptors: N-methyl-D-aspartate receptors, a type of glutamate receptor that is important for learning and memory; it is the target of drugs such as PCP and ketamine.
Persistent psychosis: Unpredictable and long-lasting visual disturbances, dramatic mood swings, and hallucinations experienced by some LSD users after they have discontinued use of the drug.
Serotonin: A neurotransmitter involved in a broad range of effects on perception, movement, and emotions. Serotonin and its receptors are the targets of most hallucinogens.
This series of reports simplifies the science of research findings for the educated lay public, legislators, educational groups, and practitioners. The series reports on research findings of national interest.