Psychoactive substances primarily interact with the brain's neurotransmitter systems. For instance, stimulants like cocaine and amphetamines increase the activity of neurotransmitters such as dopamine, leading to heightened alertness and euphoria. In contrast, depressants like alcohol and benzodiazepines enhance the effect of gamma-aminobutyric acid (GABA), producing a calming effect. Hallucinogens such as LSD alter serotonin pathways, resulting in distorted sensory perceptions.
