Which neurotransmitter is commonly targeted by antidepressants and linked to mood disorders?

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

Answer: (B)

Serotonin plays a central role in regulating mood, anxiety, sleep, and appetite, and disruptions in serotonergic signaling are closely linked to mood disorders. The most commonly used antidepressants are selective serotonin reuptake inhibitors, which block the serotonin transporter and increase serotonin levels in the synaptic cleft, enhancing serotonin signaling and often improving depressive symptoms. While other neurotransmitters like norepinephrine and dopamine also influence mood and some antidepressants affect those systems, the quintessential and most widely targeted neurotransmitter in antidepressant therapy is serotonin. Acetylcholine is not a primary target in treating mood disorders, as its main roles are in attention, memory, and neuromuscular function.