Oscillatory Acoustic-electric Stimulation in Patients With Disorders of Consciousness

Study Overview
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Brief Summary
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Altered gamma activity has been observed in several neurological and psychiatric disorders, including a reduction in gamma synchronization in patients with disorders of consciousness. Modulation of gamma oscillations with rhythmic stimulation has been used as a possible therapeutic tool. Hence, we try to use acoustic and electric stimulation at gamma frequency to restore brain oscillation and thereby to improve conscious awareness in patients with disorders of consciousness.

Detailed Description
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We propose a matched-pair parallel study in patients with disorders of consciousness to investigate whether combined acoustic and trigeminal nerve stimulation can modulate brain oscillations, as measured by electroencephalography (EEG), and whether the brain activity changes are coupled with improvements in consciousness.

Official Title
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Acoustic-electric Therapy in Patients With Disorders of Consciousness

Conditions
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Consciousness Disorder

Intervention / Treatment
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* Device: DC-Stimulator, NeuroConn, Germany


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Clinical diagnosis of disorders of consciousness based on CRS-R Time post-injury ranging from one to twelve months No history of acquired brain injury or psychiatric or neurological diseases Exclusion Criteria: Not medically stable Any contraindication to electric stimulation Hearing impairment before brain injury

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 80 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Triple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Gamma modulation effect<br>40Hz current is applied by a battery-driven current stimulator(NeuroConn, Germany). Two pairs of electrodes are attached to the middle and lower part of the face to stimulate the maxillary nerve (V2) and the mandibular nerve (V3), respectively. 40Hz acoustic stimuli and 40Hz electric stimuli are synchronously applied for 40min/day, for a total of 5 days. | Device: DC-Stimulator, NeuroConn, Germany<br>* Neurostimulation device<br>|
| Experimental: Beta modulation effect<br>28Hz current is applied by a battery-driven current stimulator. Two pairs of electrodes are attached to the middle and lower part of the face to stimulate the maxillary nerve (V2) and the mandibular nerve (V3). 28Hz acoustic stimuli and 28Hz electric stimuli are synchronously applied for 40min/day, for a total of 5 days. | Device: DC-Stimulator, NeuroConn, Germany<br>* Neurostimulation device<br>|
| Sham Comparator: Sham modulation group<br>Sham stimulation was identical to the 40Hz stimulation, except that the acoustic and electric stimulation were ramped down after 0.5 min to remain turned off for the remaining 39.5 min. Sham stimuli are applied for 40min/day, for a total of 5 days. | Device: DC-Stimulator, NeuroConn, Germany<br>* Neurostimulation device<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Coma Recovery Scale-Revised scores | Coma Recovery Scale-Revised(CRS-R) scores are the gold standard for consciousness. CRS-R consists of 23 items, grouped into 6 sub-scales: auditory, visual, motor, oromotor, communication and arousal. The lowest score on each sub-scale represents reflexive activity; the highest represents behaviors mediated by cognitive input. The total score ranges between 0 (worst) and 23 (best). | Day 1-5, Day 11-15 | 
| Neuropsychological assessment | EEG indicators could be used to assess the conscious level, including gamma oscillations and event-related potentials(P300). | Day 5 and Day 11 | 
| Glasgow Outcome Scale-Extended | A widely used index for outcomes after brain injury | 1 year after stimulation | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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disorders of consciousness, electric stimulation