Perception of Stressful Social Stimuli After Trauma Exposure.

Abnormal Processing of Stressful Social Stimuli After Trauma Exposure, in Particular After Childhood Maltreatment.

Post-traumatic stress disorder is associated with altered processing of sensory stimuli. The clinical phenotype PTSD has predominantly been described for the visual and auditory sensory modalities. However, PTSD symptoms such as intrusive memories are often evoked by olfactory and tactile cues in the environment. Moreover, little is known about whether aberrant responses to social olfactory and tactile stimuli are also present in a subclinical population.The purpose of this study is to compare trauma-exposed subjects (e.g. childhood maltreatment) with non-exposed controls in the processing of olfactory and tactile stimuli. This sensory characterizations hold potential to identify potential biomarkers for the course of trauma-related disorders and to inform trauma therapies focusing on sensory integration.

Study Overview

• Status: Completed
• Conditions: Post-traumatic Stress Disorder
• Intervention / Treatment: Behavioral: Processing of social olfactory and tactile stimuli

• Study Type: Observational
• Enrollment (Anticipated): 100

Contacts and Locations

Study Locations

• Germany
  • Bonn, Germany, 53105
    • Department of Psychiatry, University of Bonn

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 60 years (Adult)
• Accepts Healthy Volunteers: Yes
• Genders Eligible for Study: All

• Sampling Method: Probability Sample

Study Population

The study population will consist of trauma-exposed subjects and healthy controls without trauma-exposure.Patients and healthy controls will be recruited from the Bonn area.

Description

Inclusion Criteria:

• Signed informed consent
• Subjects that have experienced a traumatic event that meets the DSM-5 criteria

Exclusion Criteria:

• Schizophrenia, schizoaffective or other psychotic disorder
• Neurological disorders
• Psychotropic medication
• Subjects suffering from a respiratory tract infection or other respiratory disorder known to affect olfactory functioning at investigator's discretion
• Subjects with anosmia or other previous primary olfactory dysfunction (olfactory threshold score using the "Sniffin' Sticks" ≤ 5)
• Dermatitis of the extremities or other skin disorders that affect the skin sensitivity of the extremities

Study Plan

How is the study designed?

Number of groups / cohorts

2

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
Individuals exposed to an intentional/non-intentional trauma	Behavioral: Processing of social olfactory and tactile stimuli; Processing of social olfactory and tactile stimuli in trauma-exposed individuals and controls is examined using functional magnetic resonance imaging.
Healthy controls without trauma-exposure	Behavioral: Processing of social olfactory and tactile stimuli; Processing of social olfactory and tactile stimuli in trauma-exposed individuals and controls is examined using functional magnetic resonance imaging.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Emotion recognition ratings obtained during a forced-choice emotional face recognition task with stimuli of varying intensities (neutral to fearful).		Ratings will be assessed throughout fMRI scanning over the course of 25 minutes.
Neural substrates of social tactile stimuli processing.	fMRI scanning will be used to measure neural respones to tactile stimuli.	The neural substrates will be assessed througout fMRI scanning over the course of 20 minutes.
Valence ratings of social tactile stimuli.		Ratings will be assessed throughout fMRI scanning over the course of 20 minutes.
Neural substrates of social olfactory stimuli processing.		The neural substrates will be assessed througout fMRI scanning over the course of 25 minutes.

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Oxytocin plasma concentrations.		The oxytocin plasma concentrations of all participants will be assessed 15 minutes before fMRI scanning onset..
Olfactory performance in a n-butanol odor staircase threshold test.	Participants' olfactory performance will be assessed by administering the 'Sniffin' Sticks' test, which measures nasal chemosensory performance based on pen-like odor dispensing devices.	The olfactory threshold of all participants will be assessed in a screening session at least 24 hours prior to fMRI scanning.

Collaborators and Investigators

• Sponsor: University Hospital, Bonn
• Investigators: Principal Investigator: René Hurlemann, PhD, MD, MSc, Department of Psychiatry, University of Bonn, Germany

Publications and helpful links

Helpful Links

• Related Info

Study record dates

Study Major Dates

• Study Start (Actual): November 1, 2015
• Primary Completion (Actual): December 1, 2018
• Study Completion (Actual): December 1, 2018

Study Registration Dates

• First Submitted: August 12, 2016
• First Submitted That Met QC Criteria: January 29, 2018
• First Posted (Actual): February 5, 2018

Study Record Updates

• Last Update Posted (Actual): February 15, 2019
• Last Update Submitted That Met QC Criteria: February 13, 2019
• Last Verified: February 1, 2019

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Mental Disorders; Trauma and Stressor Related Disorders; Stress Disorders, Traumatic; Stress Disorders, Post-Traumatic
• Other Study ID Numbers: TT-Study