Neurophysiological Correlates of Exposition Therapy in Spider Phobia

Phobic Disorders Clinical Trial

Official title:

Neurophysiological Correlates of Exposition Therapy in Spider Phobia

Clinical Trial Details — Status: Recruiting

Administrative data

• NCT number: NCT03653923
• Other study ID #: 481/2018BO2
• Status: Recruiting
• Phase: N/A
• Start date: October 2018
• Est. completion date: January 2020

Study information

• Verified date: July 2018
• Source: University Hospital Tuebingen
• Contact: David Rosenbaum, Dipl.-Psych.
• Phone: 07071-29 83609
• Email: david.rosenbaum[@]med.uni-tuebingen.de
• Is FDA regulated: No
• Study type: Interventional

Clinical Trial Summary

This study aims to investigate the neurophysiological correlates of spider phobia and its treatment with CBT based Exposure Therapy. This is the first study to investigate the neurophysiological correlates of Exposure Therapy in situ by means of functional Near-Infrared Spectroscopy (fNIRS).

30 spider phobic patients will be assessed and randomly allocated to 5 sessions of exposure therapy or waiting-list. Further, 30 non-phobic control subjects will be assessed (primary assessment only).

During Exposure Therapy, changes in blood oxygenation will be measured with fNIRS in areas of the Cognitive Control Network. Regions of interest are the bilateral dorsolateral prefrontal cortex (DLPFC), bilateral inferior frontal gyrus (IFG) and somatosensory association cortex (SAC). Before the treatment, subjects will have one session of psychoeducation in which the rationale for the treatment is explained. In each therapy session subjects are exposed to 20 trials (each lasting 40s) of guided exposure by a psychotherapist. Further, 20 control trials of equal length are assessed in which subjects work with an earthworm. During the therapy additional anxiety coping strategies (e.g., controlled breathing, attention refocusing, cognitive reappraisal) are trained. After the treatment or waiting-list phase, treatment conditions are switched: The waiting list will be treated and the treated subject will wait for approximately 6 weeks.

Before treatment (primary assessment), after treatment (secondary assessment) and after study completion (final assessment), additional combined NIRS EEG measurements are done. On a peripheral physiological level heart rate and EMG of the facial corrugator supercilii are measured. During these measurements subjects are asked to watch 10s lasting video clips showing spiders (experimental condition) or pets (dogs and cats). On a psychometric level, spider phobia will be assessed by questionnaires (SPQ, FSQ, SBQ) and behavioral assessments.

Recruitment information / eligibility

• Status: Recruiting
• Enrollment: 40
• Est. completion date: January 2020
• Est. primary completion date: July 2019
• Accepts healthy volunteers: Accepts Healthy Volunteers
• Gender: All
• Age group: 18 Years to 50 Years

Eligibility

Inclusion Criteria:

• Spider Phobia or no fear of spiders

• Age between 18 and 50

• normal vision (or corrected with glasses)

• German mother tongue or comparable knowledge

Exclusion Criteria:

• pregnancy

• medication with exception of contraceptive medication

• acute or chronic disease that affects brain functioning (other mental diagnosis than spider phobia, cardial diseases, diabetes, kidney diseases, concussion)

Related Conditions & MeSH terms

• Phobic Disorders

Intervention

Behavioral:
• Exposure Therapy
Before the treatment, subjects will have one session of psychoeducation in which the rationale for the treatment is explained. In each therapy session subjects are exposed to 20 trials (each lasting 40s) of guided exposure by a psychotherapist. Further, 20 control trials of equal length are assessed in which subjects work with an earthworm. Each session lasts for approximately 90 minutes. During the therapy additional anxiety coping strategies (e.g., controlled breathing, attention refocusing, cognitive reappraisal) are trained. Subjects of the waiting-list will be treated in the second study phase.

Locations

Country	Name	City	State
Germany	Department of Psychiatry and Psychotherapy, University Hospital Tuebingen	Tuebingen	Baden-Württemberg

Sponsors (1)

Lead Sponsor	Collaborator
University Hospital Tuebingen

Country where clinical trial is conducted

Germany, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	fNIRS	Oxygenated and Deoxygenated Blood in the cerebral cortex will be measured with functional Near-Infrared Spectroscopy. Analysed will be Changes in Oxygenated Blood from Pre to Post-Measurement and between Control Conditions (EarthWorm) and Experimental Conditions (Working with Spiders). At Pre-Testing, the clinical population will be compared to the healthy controls.	Before Treatment (Primary Assessment, approximately week 1), after treatment completion (secondary assessment, approximately week 6) and after study completion (final assessment, approximately week 12); During Exposure Therapy
Secondary	spider phobia questionnaire	Range SPQ: 0 to 31, high values indicate high fear of spiders	Before Treatment (Primary Assessment, approximately week 1), after treatment completion (secondary assessment, approximately week 6) and after study completion (final assessment, approximately week 12)
Secondary	Behavioral Measures	Avoidance with respect to spiders will be assessed on a behavioral scale; = Spider is 5 m away (in a jar); = Patient watches pictures of spiders while the spider is 5 m away; = spider is 2 m away (in a jar); = spider is 0.5 m away (in a jar); = spider is directly in front of the subject (in a jar); = spider is taken out of the jar into a larger tub; = patient touches the spider with a pen; = the spider is on the (covered) hand of the patient; = patient touches the spider with his finger; = spider walks on the hand of the patient; = spider walks up the arm of the patient	Before Treatment (Primary Assessment, approximately week 1), after treatment completion (secondary assessment, approximately week 6) and after study completion (final assessment, approximately week 12)
Secondary	Peripheral Physiology	Heart rate and electromyography of the facial corrugator supercilii will be assessed	Before Treatment (Primary Assessment, approximately week 1), after treatment completion (secondary assessment, approximately week 6) and after study completion (final assessment, approximately week 12)
Secondary	EEG/EKP	Event-Related Potentials will be assessed with EEG	Before Treatment (Primary Assessment, approximately week 1), after treatment completion (secondary assessment, approximately week 6) and after study completion (final assessment, approximately week 12)
Secondary	Fear of Spiders Questionnaire	Range FSQ: 18 to 126, high values indicate high fear of spiders	Before Treatment (Primary Assessment, approximately week 1), after treatment completion (secondary assessment, approximately week 6) and after study completion (final assessment, approximately week 12)
Secondary	Spider-Phobia-Beliefs Questionnaire	Range SBQ (mean): 0 to 100%, high values indicate high maladaptive beliefs of spiders	Before Treatment (Primary Assessment, approximately week 1), after treatment completion (secondary assessment, approximately week 6) and after study completion (final assessment, approximately week 12)
Secondary	Visual analogue scales	During exposure fear, disgust and aviodance will be rated after each trial by the subject on a scale from 1 (not at all) to 9 (very much)	During each exposure session (week 1 to 5) and during EEG assessments (Before Treatment (Primary Assessment, approximately week 1), after treatment completion (secondary assessment, approximately week 6) and after study completion (approximately week 12)