A Pathological Study of Major Depressive Disorder Related to Amygdala Structure

Major depressive disorder (MDD) has severe consequences that extend beyond mental health, affecting physical health and quality of life, and raising mortality risk. The pathophysiology of MDD is still poorly understood, and current antidepressants are not completely effective. Current research identifies several key hypotheses and biochemical mechanisms involved in the pathogenesis of MDD, demonstrating that no single theory can fully explain its complexities. Recent research on MDD therapies indicates that they alter the amygdala, causing changes that can serve as markers for recovery in MDD treatment. Observations suggest that selective serotonin reuptake inhibitors, which are routinely used to treat depression, alter amygdala anatomy and function. This study used a narrative and descriptive review methodology. This review aimed to update structural and functional alterations in the amygdala that are strongly associated with MDD and its clinical symptoms. Also, some possibilities about the role of key endogenous substances were discussed, such as cortisol, epinephrine, and norepinephrine, as well as receptors for hormones and neurotransmitters in the amygdala, providing evidence and molecular mechanisms that emphasize the amygdala’s central role in MDD and its therapy.Cite this article as: Hien HTD, Bao NS, Hieu BTM, Thu NTM, Hang DTT. A pathological study of major depressive disorder related to amygdala structure. Neuropsychiatr Invest. 2025, 63, 0052, doi:10.5152/NeuropsychiatricInvest.2025.24052.