Minor tranquilizers like Valium and Librium, as well as alcohol, impact which neurotransmitter?

• A. Dopamine
• B. GABA
• C. Serotonin
• D. Acetylcholine

Answer: (B)

The key idea is that these substances boost the brain’s main inhibitory transmitter, GABA. Valium and Librium are benzodiazepines that don’t activate neurons directly; they bind to the GABA-A receptor and make GABA’s effect more potent. This increases chloride ion influx into neurons, hyperpolarizing them, and dampening neural activity—producing sedation and reduced anxiety. Alcohol acts similarly by enhancing GABA-A receptor function, contributing to its depressant effects. While other neurotransmitters like dopamine, serotonin, or acetylcholine are involved in different brain processes, the immediate, shared target of these drugs is GABA, making it the correct answer.