Which type of substance slows the nervous system?

• A. Mood Stabilizers
• B. Hallucinogens
• C. Depressants
• D. Stimulants

Answer: (C)

Depressants slow the nervous system. They dampen brain activity and slow processing, reaction time, and coordination. This happens because many depressants boost the activity of the inhibitory neurotransmitter GABA, making neurons less likely to fire and spreading the suppression across neural networks. That broad dampening produces sedation, drowsiness, and slowed reflexes, which is why this category is described as depressants. Illustrative examples include alcohol and many sedative medications, which share this general effect. In contrast, hallucinogens primarily alter perception and thought rather than calm overall CNS activity; stimulants increase CNS arousal and alertness by boosting neurotransmitter activity; mood stabilizers regulate mood states and may have calming effects but do not primarily act by slowing neural activity across the nervous system.