What emotional state is typically associated with decreased serotonin levels?

Decreased levels of serotonin in the brain are typically associated with depression. Serotonin is a neurotransmitter that plays a key role in mood regulation, and low concentrations have been widely linked to depressive symptoms. When serotonin levels are insufficient, individuals may experience persistent sadness, loss of interest in activities, and other characteristics of depression. Scientific studies have shown that medications aimed at increasing serotonin availability, such as selective serotonin reuptake inhibitors (SSRIs), can effectively alleviate depressive symptoms, thereby supporting the connection between low serotonin levels and depression.

The other choices reflect emotional states that, while they may be affected by neurotransmitter levels, are not directly linked to low serotonin in the same way depression is. For instance, anxiety can be related to various neurotransmitter systems, and happiness or excitement typically requires adequate serotonin levels to support positive mood states.