Degree Date
6-2026
Document Type
Dissertation - Public Access
Degree Name
Psy.D. Doctor of Clinical Psychology
Academic Discipline
Clinical Psychology
First Advisor
Elizabeth Lane, Ph.D.
Second Advisor
Marcia Pita, Ph.D.
Abstract
Major depressive disorder is one of the most prevalent mental health disorders worldwide. There is a vast range of treatment options for depression, with varying levels of effectiveness. Recent treatments for depression have expanded, increasing alternative treatments, and it is unknown which treatments have the largest impact on depression. This research was designed to examine the treatments of depression, with a focus on psychotherapy and contemporary treatments such as ketamine, psilocybin, and transcranial magnetic stimulation. A literature review was conducted to assess treatment outcomes and neuroplastic changes in these interventions, as well as combinations of the interventions. Data were evaluated for patterns of responses in treatment modalities, neural changes, and impact on individual symptom improvement. Results indicated long-term reduction of depression in psychotherapy approaches, with the strongest evidence for change in acceptance and commitment therapy. Additionally, rapid neuroplastic changes and symptom reduction were found following ketamine, as well as longer-term, sustained improvements following psilocybin. Primary areas of change included the amygdala, anterior cingulate cortex, the default mode network, and the prefrontal cortex. In combined modalities, a combination of psilocybin and acceptance and commitment therapy showed the greatest changes in symptom reduction and neuroplastic change. The overall findings contribute to the current known research regarding depression treatments. Understanding the neuroplastic mechanisms, as well as the clinical symptom relief of these different modalities, can inform treatment approaches and reduce strain on those with depression.
Recommended Citation
Severance, Taylor, "Evaluation of Neuroplastic Changes in Psychological Intervention and Contemporary Treatments of Depression" (2026). Dissertations. 974.
https://digitalcommons.nl.edu/diss/974
Included in
Alternative and Complementary Medicine Commons, Behavior and Behavior Mechanisms Commons, Biological Psychology Commons, Clinical Psychology Commons, Cognitive Behavioral Therapy Commons, Cognitive Science Commons, Health Psychology Commons, Mental Disorders Commons, Nervous System Commons, Other Chemicals and Drugs Commons, Other Psychiatry and Psychology Commons, Other Psychology Commons, Psychiatric and Mental Health Commons, Psychoanalysis and Psychotherapy Commons, Psychological Phenomena and Processes Commons, Therapeutics Commons