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Consciousness-Altering Drugs

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Psychology & Sociology

Depressants are substances that reduce nervous system activity by enhancing the inhibitory effects of GABA. Alcohol is a depressant that increases serotonin and dopamine levels and suppresses parts of the brain that are involved in impulsive behavior. Sedatives are also classified as depressants. Barbiturates and benzodiazepines are two common types of sedatives. In contrast, stimulants increase nervous system activity and do so by increasing serotonin, dopamine, and norepinephrine levels. Some examples of stimulants include amphetamines, cocaine, and ecstasy.

Opioids are substances that bind to opioid receptors, which ultimately results in the release of dopamine. This increase in dopamine produces effects, such as euphoria and pain relief. Hallucinogens are drugs that typically cause intensified sensory experiences or feelings and time dilation. Compared to drugs in other classes, hallucinogens have a relatively low risk of dependence. Marijuana doesn't fall cleanly into any of the drug classes as it can have stimulant, depressant, and hallucinogenic effects. Its psychoactive component, THC, exerts its effects by inhibiting GABA activity and indirectly increasing dopamine activity in the brain. Last, drug addiction is related to the mesolimbic pathway, a dopaminergic pathway that plays an important role in the rewarding effects of drugs.

Lesson Outline

<ul> <li>Introduction to consciousness-altering drugs and their effects on the brain and behavior</li> <li>Depressants</li> <ul> <li>Reduce nervous system activity</li> <li>Enhance inhibitory effects of GABA</li> <li>Effects include relaxation, drowsiness, and decreased anxiety</li> </ul> <ul><li>Types:</li> <ul><li>Alcohol</li> <ul> <li>Increases serotonin and dopamine levels</li> <li>Can cause disinhibition and impulsiveness</li> </ul> <li>Sedatives</li> <ul> <li>Induce sedation</li> <li>Examples: Barbiturates and benzodiazepines</li> </ul></ul></ul> <li>Stimulants</li> <ul> <li>Increase nervous system activity</li> <li>Boost levels of serotonin, dopamine, and norepinephrine</li> <li>Examples: Amphetamines, cocaine, and ecstasy</li> </ul> <li>Opioids</li> <ul> <li>Bind to opioid receptors</li> <li>Release of dopamine, resulting in euphoria and pain relief</li> <li>Highly addictive</li> </ul> <li>Hallucinogens</li> <ul> <li>Distorted sense of reality</li> <li>Intensified sensory experiences and time dilation</li> <li>Examples: LSD, psilocybin (shrooms), and DMT</li> </ul> <li>Marijuana</li> <ul> <li>Psychoactive compound: THC</li> <li>Inhibition of GABA activity and indirect increase in dopamine activity</li> <li>Effects can include stimulant, depressant, and hallucinogenic properties</li> </ul> <li>Addiction and the mesolimbic pathway</li> <ul> <li>Also known as the reward pathway</li> <li>Dopaminergic</li> <li>Plays an important role in addiction and reward</li> </ul> </ul>

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What are the main categories of consciousness-altering drugs and some examples of each?

Consciousness-altering drugs can be classified into four main categories: depressants, stimulants, opioids, and hallucinogens. Some examples include alcohol, barbiturates, and benzodiazepines for depressants, amphetamines and cocaine for stimulants, morphine and oxycodone for opioids, and LSD and psilocybin for hallucinogens. Tetrahydrocannabinol (THC), found in cannabis, has various effects and can be classified as both a hallucinogen and a depressant.

How do depressants like barbiturates and benzodiazepines affect brain function and neurotransmitter activity?

Depressants such as barbiturates and benzodiazepines affect brain function by enhancing the activity of the inhibitory neurotransmitter gamma-aminobutyric acid (GABA). This leads to decreased neuronal excitability, resulting in sedation, relaxation, and a reduction in anxiety. Depressants can also inhibit the release of the excitatory neurotransmitter glutamate, further reinforcing their depressive effects on the central nervous system.

What is the role of serotonin and dopamine in the effects of stimulant drugs?

Stimulant drugs, such as amphetamines and cocaine, increase the levels of dopamine and serotonin in the brain by blocking their reuptake and/or promoting their release. Dopamine is associated with the brain's reward system, and elevated levels result in feelings of euphoria and increased energy. Serotonin, on the other hand, helps regulate mood, appetite, and sleep, and increased levels can enhance mood and promote wakefulness. By elevating the concentration of these neurotransmitters in the brain, stimulants produce increased alertness, focus, and intense feelings of pleasure.

How do opioids interact with the central nervous system to produce their effects?

Opioids, such as morphine and oxycodone, produce their effects by binding to opioid receptors in the central nervous system. These receptors are involved in regulating pain, reward, and addiction. When opioids bind to these receptors, they stimulate the release of endorphins, which are the body's natural painkillers. This results in powerful analgesic effects, as well as feelings of euphoria and sedation. However, prolonged use of opioids can lead to tolerance, dependence, and addiction, posing significant risks for individuals using these drugs.

What mechanisms underlie the hallucinogenic effects of drugs like LSD and psilocybin?

The hallucinogenic effects of drugs such as LSD and psilocybin are primarily attributed to their interaction with neurotransmitter systems in the brain, particularly the serotonin system. These hallucinogens act as partial agonists at the 5-HT2A serotonin receptors, which are involved in the regulation of perception, cognition, and mood. The activation of these receptors leads to disruptions in normal perceptual and cognitive processes, often resulting in distorted perceptions, hallucinations, and altered states of consciousness.