Final answer:
Psychoactive drugs, including hallucinogens, are substances that affect perceptions, sensations, thinking, self-awareness, and emotions by changing brain function.
Step-by-step explanation:
Drugs that affect a person's perceptions, sensations, thinking, self-awareness, and emotions are known as psychoactive drugs. These substances change the function of the brain and can lead to alterations in mood, thinking, perception, and behavior. They can be prescription medications like opioid painkillers, legal substances such as nicotine and alcohol, as well as illegal drugs like LSD and heroin.
Psychoactive drugs are classified into different groups based on their pharmacological effects, including stimulants, depressants, anxiolytics, euphoriants, hallucinogens, and empathogens. Hallucinogens are a class of these drugs that profoundly alter sensory and perceptual experiences, sometimes causing users to experience visual hallucinations or an altered sense of time.
It's important to understand how both legal and illegal drugs can have psychoactive effects on the brain, which can potentially lead to addiction. Psychoactive drugs may be used for therapeutic, ritual, or recreational purposes, and their impact on the nervous system is primarily through the alteration of neurotransmitter activity.