Which neurotransmitter, when deficient, is commonly associated with clinical depression?

The neurotransmitter linked to clinical depression when deficient is serotonin. Research has established a strong connection between low levels of serotonin and the occurrence of depressive symptoms. This neurotransmitter plays a crucial role in regulating mood, anxiety, and overall emotional well-being. People with clinical depression often exhibit lower serotonin activity, which can contribute to feelings of sadness, hopelessness, and changes in appetite or sleep patterns.

The focus on serotonin in the context of depression is also evident in the effectiveness of many antidepressant medications, such as selective serotonin reuptake inhibitors (SSRIs), which work by increasing serotonin levels in the brain. This underscores the significance of serotonin in mood regulation and the therapeutic approaches used to treat depression.

In contrast, dopamine, endorphins, and GABA also play important roles in the brain's chemistry and can influence mood and mental health in various ways, but they are not primarily indicated as the key neurotransmitter affected in clinical depression specifically.