Neuroeconomics of Social Behavior Following Trauma Exposure

Sponsor

Mclean Hospital (Other)

Overall Status

Recruiting

CT.gov ID

NCT03383536

Collaborator

National Institute of Mental Health (NIMH) (NIH)

168

Enrollment

Location

57.5

Anticipated Duration (Months)

2.9

Patients Per Site Per Month

Study Details

Study Description

Brief Summary

This study will use a neuroeconomic paradigm with state-of-the-art imaging protocols to probe abnormal social reward processing underlying social withdrawal in symptomatic trauma-exposed women. By also gathering self-report measures of social anhedonia, performance on non-social and social reward valuation tasks, and measures of real-world social functioning including social network size, we aim to specify how alterations in social reward processing result in social withdrawal and functional impairment.

Condition or Disease	Intervention/Treatment	Phase
Posttraumatic Stress Disorder

Detailed Description

Impaired social functioning is a frequent and disabling sequela of trauma-related disorders. PTSD is associated with a high rate of severe impairment in quality of life relative to other anxiety disorders, including panic disorder, social phobia, and OCD, with particularly marked impairment in social quality of life. Mounting evidence indicates that impairment in quality of life in PTSD is strongly related to its effect on social functioning. Such difficulties are widespread and affect multiple social networks, including marital relationships, and friendships and family relationships. Social withdrawal, defined here in terms of reduced social network size, is of particular interest because of its strong relationship with health outcomes, including increased risk of disability, reduced immune response, and increased mortality risk; most critically, poor social integration is associated with a threefold increase in suicide risk. Because women are at a 2.3-to-3-fold increased risk compared to men of developing PTSD following trauma, understanding the differential neurobiological pathways that may contribute to the development of stress-related disorders in women is particularly critical. Women are more likely than men to endorse social detachment following trauma, especially when the trauma involves exposure to violence.

In this project, we propose abnormal reward processing (anhedonia) as a specific mechanism underlying social withdrawal in trauma-exposed women, and we present a paradigm that capitalizes on advances in neuroeconomics to elucidate the neural underpinnings of social withdrawal. Additionally, we propose to identify the possible influences of a stress peptide (pituitary adenylate cyclase-activating polypeptide: PACAP) implicated in sex-specific changes in social behavior following stress exposure.

Study Design

Study Type:

Observational

Anticipated Enrollment :

168 participants

Observational Model:

Case-Control

Time Perspective:

Cross-Sectional

Official Title:

Social Withdrawal Following Trauma Exposure: a Neuroeconomic Approach

Actual Study Start Date :

Nov 14, 2017

Anticipated Primary Completion Date :

Aug 31, 2022

Anticipated Study Completion Date :

Aug 31, 2022

Arms and Interventions

Arm	Intervention/Treatment
Phase 1 Healthy control participants will provide neuroeconomic game responses to form a pool of potential responses for participants to interact with during Phase 2.
Phase 2: PTS-SA posttraumatic spectrum-socially anhedonic
Phase 2: PTS-nonSA posttraumatic spectrum-non-socially anhedonic
Phase 2: HC healthy controls

Outcome Measures

Primary Outcome Measures

Group differences in neuroeconomic game performance [Measured on the day of the MRI scan]
Compared to the PTS-nonSA and HC groups, the PTS-SA group will demonstrate lower investments and slower learning rates on the Trust Task than on the non-social risk task compared with PTS-nonSA and HC subjects
Group differences in fMRI BOLD signal [Measured on the day of the MRI scan]
The HC and PTS-nonSA groups will show greater ventral striatum (VS), dorsal striatum (DS), and medial prefrontal cortex (mPFC) responses during the outcome phase of the trust game for 'share' versus baseline, compared to the PTS-SA group, for the real partner condition (Trust Task), but not for the risk task.
Correlations between behavior and fMRI BOLD signal [Measured on the day of the MRI scan]
Because social withdrawal will occur in response to reduced social reward value, we hypothesize that across the PTS groups, reduced VS, DS, and mPFC activity during the outcome phase of the trust game for 'share' outcomes will be associated with lower Trust Task investments, greater self-reported social anhedonia, and smaller social network size.
PACAP correlations [Measured on the day of the MRI scan]
Elevated PACAP levels will be associated with lower investments on the Trust Task; decreased social reward signals during the outcome phase for 'share' outcomes in the VS, DS, and mPFC; and smaller social network size.

Secondary Outcome Measures

Mediation analysis [Measured on the day of the MRI scan]
Within the PTS groups, decreased VS, DS, and mPFC response to 'share' outcomes will mediate the relationship between social anhedonia and reduced social network size.
Functional connectivity (psychophysiological interaction) [Measured on the day of the MRI scan]
PTS individuals with higher self-reported social anhedonia and social withdrawal will show reduced VS-mPFC connectivity for social rewards on the Trust Task.

Eligibility Criteria

Criteria

Ages Eligible for Study:

18 Years to 45 Years

Sexes Eligible for Study:

Female

Accepts Healthy Volunteers:

Yes

Phase 1:

Inclusion Criteria:

Age 18-45
Self-reported healthy volunteer status

Exclusion Criteria:

Inability to provide written informed consent in English
Inability to see task due to visual impairment
Participants who produce T-scores of 65 or higher on any Brief Symptom Inventory (BSI) subscales will not be eligible to remain in the Trust Task participant pool.

Phase 2:

Inclusion Criteria:

Female
Trauma exposure appropriate to group
For trauma-exposed groups the index trauma is actual or threatened physical assault or sexual violence
PCL-5 score 33 and above (for PS-SA and PS-nonSA groups)
Right handedness
Age 18-45
English as a first language

Exclusion Criteria:

History of neurological illness (including head injury with loss of consciousness > 5 minutes)
Medical conditions that may influence neuroimaging (e.g. HIV)
Current or past DSM-5 Axis I disorder (for HC group)
History of bipolar disorder or schizophrenia spectrum disorder
Contraindications for MRI
Alcohol dependence in the past 5 years
Substance dependence in the past 3 years
Daily substance use in the past year
Prescribed psychotropic medication use in the past month
Wechsler Abbreviated Scale of Intelligence- Second Edition (WASI-II) FSIQ < 70.