Introduction to Psychology

Saylor URL: http://www.saylor.org/books Saylor.org

[26] Hobson, J. A., & McCarley, R. (1977). The brain as a dream state generator: An activation-synthesis hypothesis of the dream
process. American Journal of Psychiatry, 134, 1335–1348; Hobson, J. A. (2004). Dreams Freud never had: A new mind
science. New York, NY: Pi Press.

5.2 Altering Consciousness With Psychoactive Drugs

LEARNING OBJECTIVES

1. Summarize the major psychoactive drugs and their influences on consciousness and behavior.


2. Review the evidence regarding the dangers of recreational drugs.

A psychoactive drug is a chemical that changes our states of consciousness, and particularly our
perceptions and moods. These drugs are commonly found in everyday foods and beverages,
including chocolate, coffee, and soft drinks, as well as in alcohol and in over-the-counter drugs,
such as aspirin, Tylenol, and cold and cough medication. Psychoactive drugs are also frequently
prescribed as sleeping pills, tranquilizers, and antianxiety medications, and they may be taken,
illegally, for recreational purposes. As you can see in Table 5.1 "Psychoactive Drugs by Class",
the four primary classes of psychoactive drugs are stimulants, depressants, opioids,
and hallucinogens.

Psychoactive drugs affect consciousness by influencing how neurotransmitters operate at the
synapses of the central nervous system (CNS). Some psychoactive drugs are agonists, which
mimic the operation of a neurotransmitter; some are antagonists, which block the action of a
neurotransmitter; and some work by blocking the reuptake of neurotransmitters at the synapse.

Table 5.1 Psychoactive Drugs by Class

Mechanism Symptoms Drug

Dangers and side

effects

Psychological

dependence

Physical

dependence

Addiction

potential

Addiction

potential

Stimulants

Stimulants block the
reuptake of dopamine,
norepinephrine, and
serotonin in the
synapses of the CNS.

Enhanced mood

and increased

energy

Caffeine

May create

dependence Low Low Low

Nicotine

Has major

negative health

effects if smoked High High High