Boosting Reward-based Attention Through VEstibular STimulation (BRAVEST)

The exploration of space is more effective when intrinsically rewarding elements are located in the visual scene. Thus, rewards could be exploited as a novel rehabilitation approach to various attentional disorders. The first part of the project aims to characterize these effects at the behavioural level. The interventional part consists then in the administration of Caloric Vestibular Stimulation (CVS), which by means of injection of a small quantity of water in the external ear activates the vestibular organs and subsequently vestibular-related brain areas. Among the observed brain activations, the possibility to reach cingulate areas appears particularly interesting because it foreshadows the possibility to further enhance attentional capture by rewards.

CVS will be delivered to patients with brain lesion of the right hemisphere, engaged in cancellation tasks requiring the processing of targets of different nature (e.g. monetary or neutral). The main prediction is that CVS administration would enhance spatial exploration in terms of center of gravity of the cancellation and improved accuracy as a function of the type of target processed (e.g. its value).

Study Overview

• Status: Suspended
• Conditions: Brain Lesion of the Right Hemisphere; Unilateral Spatial Neglect for Half of Them
• Intervention / Treatment: Procedure: Non-invasive brain stimulation of the vestibular system through caloric vestibular stimulation.; Procedure: Non-invasive brain stimulation of the vestibular system through caloric vestibular stimulation.

• Study Type: Interventional
• Enrollment (Anticipated): 60
• Phase: Not Applicable

Contacts and Locations

Study Locations

• France
  • Bron, France, 69500
    • CRNL, équipe IMPACT (CNRS UMR5292, INSERM U1028)
  • Saint-Genis-Laval, France, 69230
    • Service de médecine et réadaptation neurologique, Hôpital Henry Gabrielle

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 85 years (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• More than 18 years of age, less than 85
• right handed
• Benefit of social health security
• Normal or corrected-to-normal vision
• Brain lesion localised in the right hemisphere, confirmed by CT or MRI

Exclusion Criteria:

• Anamnesis of neurological of psychiatric illness
• Pregnancy or breastfeeding
• Administrative measures restricting legal rights
• Recent participation to other brain stimulation studies (< 1 week)
• Perforation of the tympanic membrane
• Anamnesis of recurrent otitis media

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Basic Science
• Allocation: Non-Randomized
• Interventional Model: Crossover Assignment
• Masking: Single

Number of Arms

3

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Caloric Vestibular Stimulation, Left-Warm; Caloric Vestibular Stimulation (CVS) stimulates the vestibular system through thermic currents applied through small quantity of water injected in the external ear. The Left-Warm condition uses water with a temperature of 44°. It induces a nystagmus with its slow phase towards the right.	Procedure: Non-invasive brain stimulation of the vestibular system through caloric vestibular stimulation.; Caloric vestibular stimulation (CVS) involves the irrigation of cold or warm water into the external ear canal, and induces a temperature gradient across the semicircular canals stimulating the vestibular nerve. It is commonly used in both otolaryngology to assess vestibular function and neurology to test brain stem function.; Procedure: Non-invasive brain stimulation of the vestibular system through caloric vestibular stimulation.; Caloric vestibular stimulation (CVS) involves the irrigation of cold or warm water into the external ear canal, and induces a temperature gradient across the semicircular canals stimulating the vestibular nerve. It is commonly used in both otolaryngology to assess vestibular function and neurology to test brain stem function. The SHAM condition uses body-temperature water, and thus does not result into vestibular unbalance.
Experimental: Caloric Vestibular Stimulation, Left-Cold; Caloric Vestibular Stimulation (CVS) stimulates the vestibular system through thermic currents applied through small quantity of water injected in the external ear. The Left-Cold condition uses water with a temperature of 30°. It induces a nystagmus with its slow phase towards the left.	Procedure: Non-invasive brain stimulation of the vestibular system through caloric vestibular stimulation.; Caloric vestibular stimulation (CVS) involves the irrigation of cold or warm water into the external ear canal, and induces a temperature gradient across the semicircular canals stimulating the vestibular nerve. It is commonly used in both otolaryngology to assess vestibular function and neurology to test brain stem function.; Procedure: Non-invasive brain stimulation of the vestibular system through caloric vestibular stimulation.; Caloric vestibular stimulation (CVS) involves the irrigation of cold or warm water into the external ear canal, and induces a temperature gradient across the semicircular canals stimulating the vestibular nerve. It is commonly used in both otolaryngology to assess vestibular function and neurology to test brain stem function. The SHAM condition uses body-temperature water, and thus does not result into vestibular unbalance.
Sham Comparator: Caloric Vestibular Stimulation, SHAM; The SHAM condition uses water with a temperature of 37°. It does not induce nystagmus	Procedure: Non-invasive brain stimulation of the vestibular system through caloric vestibular stimulation.; Caloric vestibular stimulation (CVS) involves the irrigation of cold or warm water into the external ear canal, and induces a temperature gradient across the semicircular canals stimulating the vestibular nerve. It is commonly used in both otolaryngology to assess vestibular function and neurology to test brain stem function.; Procedure: Non-invasive brain stimulation of the vestibular system through caloric vestibular stimulation.; Caloric vestibular stimulation (CVS) involves the irrigation of cold or warm water into the external ear canal, and induces a temperature gradient across the semicircular canals stimulating the vestibular nerve. It is commonly used in both otolaryngology to assess vestibular function and neurology to test brain stem function. The SHAM condition uses body-temperature water, and thus does not result into vestibular unbalance.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Center of Gravity (pixels).	For line bisection defined as the difference between participants' mark and the objective center of the line. For cancellation tasks it is calculated as the grand average of horizontal and vertical coordinates of all the marks. In both cases smaller indices indicate a leftward exploration bias, whereas larger indices indicate rightward bias.	Days 1, 2, and 3

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Reaction times (ms).	The speed of response is a traditional indicator of the amount of cognitive processing underneath provided responses. It is measured by professional programs (e.g. Presentation) running on standard PCs	Days 1, 2, and 3.
Response accuracy (%)	The proportion of correct responses provided, automatically computed by professional programs (e.g. Presentation) running on standard PCs.	Days 1, 2, and 3.

Collaborators and Investigators

• Sponsor: Hospices Civils de Lyon

Study record dates

Study Major Dates

• Study Start (Actual): April 23, 2018
• Primary Completion (Actual): May 8, 2018
• Study Completion (Anticipated): February 13, 2023

Study Registration Dates

• First Submitted: July 6, 2017
• First Submitted That Met QC Criteria: July 6, 2017
• First Posted (Actual): July 11, 2017

Study Record Updates

• Last Update Posted (Actual): February 15, 2023
• Last Update Submitted That Met QC Criteria: February 13, 2023
• Last Verified: February 1, 2023

More Information

Terms related to this study

• Keywords: Brain Stimulation; Reward; Caloric Vestibular Stimulation Reward; Vestibular System; Cingulate Cortex; Cancellation Tasks
• Other Study ID Numbers: 69HCL17_0263; 2017-A01784-49 (Other Identifier: ID-RCB)

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No