EPPP Physiology Practice Exam 2026 – Comprehensive Prep Tool

Low levels of serotonin are closely linked to various mental health conditions, most notably depression and aggression. Serotonin is a neurotransmitter that plays a pivotal role in mood regulation, emotional stability, and overall mental well-being. When serotonin levels are diminished, it can lead to dysregulation of mood, which is a hallmark of depression. Individuals with depression may experience feelings of sadness, hopelessness, and a loss of interest in daily activities, all of which can be attributed to insufficient serotonin levels.

Furthermore, the relationship between low serotonin levels and aggression is also noteworthy. Research suggests that decreased serotonin activity can be associated with increased impulsive behaviors and irritability, which can manifest as aggression in some individuals. This connection underscores the complex role serotonin plays in both mood modulation and behavioral regulation.

In contrast, other mental health issues mentioned, such as Alzheimer's, schizophrenia, autism, PTSD, and ADHD, may involve a variety of neurochemical imbalances and other factors, but they do not primarily hinge on serotonin levels in the same way that depression and aggression do. Therefore, the association between low serotonin and these two specific mental health issues is particularly well established, emphasizing the critical role that serotonin plays in emotional and behavioral health.