Which neurotransmitter is commonly found in the brain and is essential for mood regulation?

Serotonin is a key neurotransmitter that plays a significant role in mood regulation. It is widely recognized for its influence on emotional states, social behavior, sleep, appetite, digestion, and memory. Low levels of serotonin have been associated with mood disorders such as depression and anxiety, highlighting its essential function in maintaining emotional balance. The pathways in which serotonin operates involve various brain areas, including the limbic system, which is crucial for processing emotions.

In contrast, while glutamate is the primary excitatory neurotransmitter involved in synaptic plasticity and cognitive functions, it is not specifically linked to mood regulation. GABA serves as the main inhibitory neurotransmitter in the brain, helping to reduce neuronal excitability throughout the nervous system, but it does not directly regulate mood like serotonin does. Endorphins are neuropeptides that are often associated with pain relief and the sensation of pleasure, which can affect mood but are not primarily responsible for its regulation. Thus, serotonin stands out as the neurotransmitter most directly connected with mood control.