Perception of Stressful Social Stimuli After Trauma Exposure.

Completed

• Conditions: Post-traumatic Stress Disorder
• Interventions: Behavioral: Processing of social olfactory and tactile stimuli

• Registration Number: NCT03421587
• Lead Sponsor: University Hospital, Bonn

Brief Summary

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.

Detailed Description

Not available

Study Timeline

• Study Start: 2015-11
• Study First Submitted: 2016-08-12
• Study First Submitted QC: 2018-01-29
• Study First Posted: 2018-02-05
• Primary Completion: 2018-12
• Study Completion: 2018-12
• Status Verified: 2019-02
• Last Update Submitted: 2019-02-13
• Last Update Posted: 2019-02-15

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 100

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 & Design

• Study Type: OBSERVATIONAL
• Study Design: Not specified

Arm && Interventions

Group	Intervention	Description
Healthy controls without trauma-exposure	Processing of social olfactory and tactile stimuli	-
Individuals exposed to an intentional/non-intentional trauma	Processing of social olfactory and tactile stimuli	-

Primary Outcome Measures

Name	Time	Method
Neural substrates of social tactile stimuli processing.	The neural substrates will be assessed througout fMRI scanning over the course of 20 minutes.	fMRI scanning will be used to measure neural respones to tactile stimuli.
Valence ratings of social tactile stimuli.	Ratings will be assessed throughout fMRI scanning over the course of 20 minutes.
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 olfactory stimuli processing.	The neural substrates will be assessed througout fMRI scanning over the course of 25 minutes.

Secondary Outcome Measures

Name	Time	Method
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.	The olfactory threshold of all participants will be assessed in a screening session at least 24 hours prior to fMRI scanning.	Participants' olfactory performance will be assessed by administering the 'Sniffin' Sticks' test, which measures nasal chemosensory performance based on pen-like odor dispensing devices.

Trial Locations

Locations (1)

Department of Psychiatry, University of Bonn; 🇩🇪 Bonn, Germany