NCT03048370

Reactivity of the Vestibular System to Caloric Vestibular Stimulation in Schizophrenia

• Status: Completed
• Phase: N/A
• Study type: Interventional
• Enrollment: 40 (actual)
• Sponsor: Centre for Addiction and Mental Health · Academic / Other
• Sex: All
• Age: 18 Years
• Healthy volunteers: Accepted

Summary

This study aims to determine if individuals with schizophrenia have greater reactivity to vestibular stimulation than healthy controls. The physiological response of vestibular stimulation will be assessed with electronystagmography, which provides a measure of the intensity of the nystagmus via PSPV. Positive results would suggest greater vestibular system reactivity to vestibular stimulation may be a biomarker of schizophrenia. Pathophysiologically, increased vestibular reactivity to vestibular stimulation may reflect abnormal vestibular function or impaired central suppression of the vestibular ocular reflex.

Detailed description

In schizophrenia, there is no conclusive link between psychopathology and vestibular dysfunction and we are not aware of any data that exists on the range of responses to caloric vestibular stimulation (CVS) in persons with schizophrenia. Initial data from another CVS study from our group suggests individuals with schizophrenia have greater reactivity to body temperature (37°C) CVS, as measured by the peak slow phase velocity of the resulting nystagmus (PSPV), than would be expected from individuals without schizophrenia versus healthy participants. Intriguingly, CVS at 37°C should not theoretically produce a significant vestibulocular reflex response due to the stimulus' approximation to body temperature. Hence, the primary aim of this study is to determine if individuals with schizophrenia will have greater vestibular reactivity, as measured by nystagmus PSPV, to CVS in comparison with healthy participants. The secondary aim is to assess illness awareness pre and post CVS administration in attempts to replicate our previous observation. A total of 20 patients with schizophrenia and 20 healthy control participants will be recruited. All participants will receive three conditions bilaterally: (1) body temperature (37°C) vestibular stimulation; (2) warm CVS (44°C), and (3) cold CVS (30°C).

Conditions

• Schizophrenia
• Healthy

Interventions

Type	Name	Description
PROCEDURE	Left body temperature VS	Caloric vestibular stimulation (CVS), which involves the irrigation of cold or warm water into the external ear canal, induces a temperature gradient across the semicircular canals of the vestibular apparatus stimulating the vestibular nerve. It is commonly used in both otolaryngology to assess vestibular function and neurology to test brain stem function
PROCEDURE	Right body temperature VS	Caloric vestibular stimulation (CVS), which involves the irrigation of cold or warm water into the external ear canal, induces a temperature gradient across the semicircular canals of the vestibular apparatus stimulating the vestibular nerve. It is commonly used in both otolaryngology to assess vestibular function and neurology to test brain stem function
PROCEDURE	Left warm CVS	Caloric vestibular stimulation (CVS), which involves the irrigation of cold or warm water into the external ear canal, induces a temperature gradient across the semicircular canals of the vestibular apparatus stimulating the vestibular nerve. It is commonly used in both otolaryngology to assess vestibular function and neurology to test brain stem function
PROCEDURE	Right warm CVS	Caloric vestibular stimulation (CVS), which involves the irrigation of cold or warm water into the external ear canal, induces a temperature gradient across the semicircular canals of the vestibular apparatus stimulating the vestibular nerve. It is commonly used in both otolaryngology to assess vestibular function and neurology to test brain stem function
PROCEDURE	Left cold CVS	Caloric vestibular stimulation (CVS), which involves the irrigation of cold or warm water into the external ear canal, induces a temperature gradient across the semicircular canals of the vestibular apparatus stimulating the vestibular nerve. It is commonly used in both otolaryngology to assess vestibular function and neurology to test brain stem function
PROCEDURE	Right cold CVS	Caloric vestibular stimulation (CVS), which involves the irrigation of cold or warm water into the external ear canal, induces a temperature gradient across the semicircular canals of the vestibular apparatus stimulating the vestibular nerve. It is commonly used in both otolaryngology to assess vestibular function and neurology to test brain stem function

Timeline

• Start date: 2019-01-01
• Primary completion: 2023-12-31
• Completion: 2023-12-31
• First posted: 2017-02-09
• Last updated: 2024-02-08

Locations

1 site across 1 country: Canada