Which neurotransmitter is primarily involved in mood regulation and is commonly affected in mood disorders?

Serotonin is primarily involved in mood regulation and is a key neurotransmitter that impacts emotional states. It plays a crucial role in various bodily functions, including the regulation of mood, appetite, and sleep. Because of its significant effect on mood, imbalances in serotonin levels have been strongly linked to several mood disorders, such as depression and anxiety.

Research indicates that many treatment strategies for mood disorders aim to increase serotonin levels in the brain, thus alleviating symptoms of these disorders. For instance, selective serotonin reuptake inhibitors (SSRIs) are a common class of antidepressants that work by preventing the reabsorption of serotonin, making more of it available in the synaptic cleft and leading to improved mood.

The other neurotransmitters listed have different roles; for example, dopamine is associated with the brain's reward system and does play a role in mood but is more directly linked to motivation and pleasure. Norepinephrine is involved in arousal and alertness and is also relevant in mood disorders but not as directly as serotonin. GABA primarily functions as the main inhibitory neurotransmitter in the brain, helping to calm neuronal activity, but it does not specifically regulate mood to the same extent as serotonin. Thus, serotonin's well-established connection to