Neural changes following equine-assisted therapy for posttraumatic stress disorder: A longitudinal multimodal imaging study

Xi Zhu; Benjamin Suarez-Jimenez; Sigal Zilcha-Mano; Amit Lazarov; Shay Arnon; Ari L Lowell; Maja Bergman; Matthew Ryba; Allan J Hamilton; Jane F Hamilton; J Blake Turner; John C Markowitz; Prudence W Fisher; Yuval Neria

doi:10.1002/hbm.25360

Neural changes following equine-assisted therapy for posttraumatic stress disorder: A longitudinal multimodal imaging study

Hum Brain Mapp. 2021 Apr 15;42(6):1930-1939. doi: 10.1002/hbm.25360. Epub 2021 Feb 5.

Authors

Xi Zhu^{1

2}, Benjamin Suarez-Jimenez^{1

2

3}, Sigal Zilcha-Mano⁴, Amit Lazarov^{1

5}, Shay Arnon², Ari L Lowell^{1

2

6}, Maja Bergman², Matthew Ryba², Allan J Hamilton⁷, Jane F Hamilton⁸, J Blake Turner^{1

2}, John C Markowitz^{1

2}, Prudence W Fisher^{1

2}, Yuval Neria^{1

2

9}

Affiliations

¹ Department of Psychiatry, Columbia University, New York, New York, USA.
² New York State Psychiatric Institute, New York, New York, USA.
³ Neuroscience Department, University of Rochester, Rochester, New York, USA.
⁴ Department of Psychology, University of Haifa, Haifa, Israel.
⁵ School of Psychological Sciences, Tel Aviv University, Tel Aviv, Israel.
⁶ Memphis Veterans Administration Medical Center, Memphis, Tennessee, USA.
⁷ The University of Arizona Health Sciences, Tucson, Arizona, USA.
⁸ Rancho Bosque Equestrian Center of Excellence, House Hamilton Business Group, PLC, Tucson, Arizona, USA.
⁹ Department of Epidemiology, Columbia University Irving Medical Center, New York, New York, USA.

Abstract

Background: While effective treatments for posttraumatic stress disorder (PTSD) exist, many individuals, including military personnel and veterans fail to respond to them. Equine-assisted therapy (EAT), a novel PTSD treatment, may complement existing PTSD interventions. This study employs longitudinal neuro-imaging, including structural magnetic resonance imaging (sMRI), resting state-fMRI (rs-fMRI), and diffusion tensor imaging (DTI), to determine mechanisms and predictors of EAT outcomes for PTSD.

Method: Nineteen veterans with PTSD completed eight weekly group sessions of EAT undergoing multimodal MRI assessments before and after treatment. Clinical assessments were conducted at baseline, post-treatment and at 3-month follow-up.

Results: At post-treatment patients showed a significant increase in caudate functional connectivity (FC) and reduction in the gray matter density of the thalamus and the caudate. The increase of caudate FC was positively associated with clinical improvement seen immediately at post-treatment and at 3-month follow-up. In addition, higher baseline caudate FC was associated with greater PTSD symptom reduction post-treatment.

Conclusions: This exploratory study is the first to demonstrate that EAT can affect functional and structural changes in the brains of patients with PTSD. The findings suggest that EAT may target reward circuitry responsiveness and produce a caudate pruning effect from pre- to post-treatment.

Trial registration: ClinicalTrials.gov NCT03068325.

Keywords: PTSD; equine assisted therapy; neuroimaging; resting state fMRI.

Publication types

Clinical Trial
Research Support, Non-U.S. Gov't

MeSH terms

Adult
Caudate Nucleus* / diagnostic imaging
Caudate Nucleus* / pathology
Caudate Nucleus* / physiopathology
Connectome
Diffusion Tensor Imaging
Equine-Assisted Therapy*
Female
Humans
Longitudinal Studies
Magnetic Resonance Imaging*
Male
Middle Aged
Multimodal Imaging
Neuroimaging*
Reward
Stress Disorders, Post-Traumatic* / diagnostic imaging
Stress Disorders, Post-Traumatic* / pathology
Stress Disorders, Post-Traumatic* / physiopathology
Stress Disorders, Post-Traumatic* / rehabilitation
Treatment Outcome

Associated data

ClinicalTrials.gov/NCT03068325

Grants and funding

K01 MH122774/MH/NIMH NIH HHS/United States