Evaluation of the Feasibility and Efficacy of a Chronic Brain-computer Interface for Speech Rehabilitation in Patients With Locked-in-syndrome (LIS) (SpeechBCI)

Eighteen million people worldwide are affected by speech disorders. Locked-in syndrome (LIS) represents the most extreme form of communication disability resulting from motor impairment. In France, the Association du Locked-In Syndrome (ALIS) reports approximately 500 individuals with LIS, most of whom live at home. The quality of life of people with LIS depends strongly on their ability to communicate, and speech synthesis is the mode of communication restoration most desired by individuals with LIS. Several surveys have shown that improving communication abilities in these individuals leads to a significant improvement in their quality of life as well as that of their caregivers.

Natural speech allows the production of an average of 150 words per minute. Non-invasive communication methods, whether based on residual motor function (eye-blink code) or on brain-machine or brain-computer interfaces (Brain-Computer Interface, BCI) using scalp electroencephalographic (EEG) signals, involve a high cognitive load and have low efficiency (spelling only a few letters per minute). Invasive BCIs for speech rehabilitation aim to overcome the limitations of non-invasive devices (cognitive overload and slow speech rate). The intention to act (the act of speaking) is predicted by an algorithm based on the direct decoding of neuronal activity from the sensorimotor cortex (the area where articulatory muscles are represented).

To date, studies testing speech rehabilitation BCIs in humans remain rare. A subdural electrocorticographic (ECoG) invasive BCI enabled speech decoding (words and sentences from a limited repertoire) for chronic use (2 years). Real-time control of an on-screen cursor allowing spelling of up to 90 letters per minute (equivalent to text messaging) has also been achieved using an intracortical invasive BCI (Utah Array). Very recently, up to 60 words per minute were produced using an intracortical invasive BCI (Utah Array) implanted in the ventral premotor cortex, although with a connector potentially contaminated by acoustic audio feedback. Furthermore, these devices still rely on transcutaneous connectors, which may be sources of infection and prevent routine daily-life use.

In summary, there is currently no fully implantable, wireless invasive "speech BCI" with real-time speech synthesis suitable for long-term home use. The present study will use an intracranial extradural invasive BCI combined with a speech synthesizer, with the aim of developing a communication tool suitable for everyday use. More specifically, the SpeechBCI protocol will propose two complementary BCI approaches in the same subject: a speech BCI (primary objective, BCI_PAROLE device) and a cursor BCI (secondary objective). Both BCIs will use the WIMAGINE intracranial epidural system, enabling ECoG signal acquisition with a very limited risk of infection and brain injury and providing signals that are more stable over time compared with intracortical or subdural ECoG devices that retain transcutaneous connectors. These systems will allow long-term and ecological use, as the WIMAGINE implant is wireless and offers excellent long-term signal stability. The WIMAGINE implant has already been successfully tested for controlling an exoskeleton in a tetraplegic subject (operational for over 6 years) and very recently for controlling walking in real-life conditions via a spinal cord stimulator in a paraplegic individual.

The BCI_PAROLE device will integrate a speech synthesizer providing real-time auditory feedback to the speaker. The BCI-CURSEUR device will allow the subject to control an on-screen cursor to access various communication functionalities (web access, emails, chats, etc.). This will provide a complementary communication solution to real-time speech production.

The hypothesis of this stydy is that the intention to speak (attempted speech) will be decoded by the BCI_PAROLE device in individuals with LIS because, as with limb paralysis, paralysis of articulatory and phonatory muscles does not prevent the corresponding cortical map from producing specific signals. Similarly, the BCI-CURSEUR device will decode the intention to move a cursor and perform actions on a computer screen.

Neuronal electrical signals will be recorded bilaterally from the ventral motor cortex (representation of lips, cheeks, tongue, palate, and larynx-the vocal tract) and from the dorsal part of the motor cortex (larynx and hand, the latter for controlling a two-degree-of-freedom cursor), using a total of 128 electrodes (64 on each cerebral hemisphere). The implant will be optimally positioned over speech motor areas using preoperative functional imaging in order to optimize speech decoding by the BCI_PAROLE device.

Study Overview

• Status: Not yet recruiting
• Conditions: ALS (Amyotrophic Lateral Sclerosis); Locked in Syndrome
• Intervention / Treatment: Device: Chronic speech BCI

• Study Type: Interventional
• Enrollment (Estimated): 3
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Amina FONTANELL; Phone Number: (33) 456520389; Email: lafontanell@chu-grenoble.fr
• Study Contact Backup: Name: Blaise Yvert; Phone Number: (33) 6 32 88 75 90; Email: blaise.yvert@inserm.fr

Study Locations

• France
  • Garches, France, 92380
    • Hôpital Raymond Poincaré Garches
    • Contact: Jonathan LEVY, Doctor; Phone Number: (33) 1 47 10 70 86; Email: jonathan.levy2@aphp.fr
    • Contact: Amina FONTANELL; Phone Number: (33) 4 56 52 03 89; Email: lafontanell@chu-grenoble.fr
    • Principal Investigator: Jonathan LEVY, Doctor
  • Grenoble, France, 38000
    • Centre hospitalier Grenoble
    • Contact: Blaise Yvert; Phone Number: (33) 6 32 88 75 90; Email: blaise.yvert@inserm.fr
    • Contact: Amina FONTANELL; Phone Number: (33) 4 56 52 03 89; Email: lafontanell@chu-grenoble.fr
    • Principal Investigator: Stephan CHABARDES, Professor
  • Nîmes, France, 30900
    • Centre hospitalier Nimes
    • Contact: Simon BERTRAND, Doctor; Phone Number: (33) 4 66 68 34 59; Email: simon.bertrand@chu-nimes.fr
    • Contact: Amina FONTANELL; Phone Number: (33) 4 56 52 03 89
    • Principal Investigator: Simon BERTRAND, Doctor
  • Saint-Etienne, France, 42100
    • Centre hospitalier saint Etienne
    • Contact: Amina FONTANELL; Phone Number: (33) 4 56 52 03 89; Email: lafontanell@chu-grenoble.fr
    • Contact: Lydia OUJAMAA, Doctor; Phone Number: (33) 4 77 12 03 34; Email: lydia.oujamaa@chu-st-etienne.fr
    • Principal Investigator: Lydia OUJAMAA

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

a. Male or female between 18 and 65 years old b. French speaking person c. Person in locked in syndrome with a severe speech disorder following either: i. A subcortical stroke ii. Amyotrophic Lateral Sclerosis. d. Person with stable clinical state (esp. regarding respiratory state) e. Person able to read on a screen (sufficient eye movement control) f. Negative plasma pregnancy test for women of childbearing potential* g. Highly effective or at least acceptable** contraception for women of childbearing potential.

h. Persistence of localizing signals of language function proven by functional MRI.

i. Person able to perform a simple BCI task with MEG j. Person with a neuropsychological profile evaluated by psychiatrist as compatible with sustain BCI training k. Informed consent to participate in the obtained using their usual means and code of communication (residual vocalizations, eye-blinking code, pictograms, eye tracking, alphabet chart, etc.), in the presence of their trusted person or curator who is accustomed to communicating with them using this means.

l. Person affiliated to the French social security system or beneficiary of such a system

Exclusion Criteria:

Patients with any of the following criteria cannot be included in this investigation:

1. Severe cognitive disorders assessed after a neuropsychological evaluation
2. Deafness
3. Continuous assisted ventilation
4. Contraindication to intracranial surgery
5. Contra-indication to MRI (1.5T), CT-scan or their related contrast agent injection or MEG examinations.
6. Anatomical brain MRI showing structural abnormalities in the cortical areas of language
7. Functional impairment of language cortical areas on MRI
8. Auditory evoked potential showing hearing impairment
9. Person with a skull shape incompatible with one WIMAGINE implant on each hemisphere
10. Persons referred to in Articles L1125-7 of the Public Health Code and article 64 of MDR(corresponding to all protected persons: pregnant women, women in labor, breastfeeding mothers, minors, persons deprived of liberty by judicial or administrative decision.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Device Feasibility
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: The subject serves as their own control in a crossover design.; Chronic speech BCI	Device: Chronic speech BCI; Chronic speech BCI

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
safety of the implant	Serious adverse events associated with chronic implantation with an extradural ECoG implant, especially infection, chronic pain and neurological complication.	2 years after surgery
Faisability of the SpeechBCI	Successful real-time synthesis of at least 20 different intelligible speech items (vowels, words or short sentences) above chance level from brain activity after 12 months training post-implantation.	1year after surgery to 2 years after surgery

Collaborators and Investigators

• Sponsor: University Hospital, Grenoble
• Collaborators: Centre Hospitalier Universitaire de Saint Etienne; Centre Hospitalier Universitaire de Nīmes; ALS Association; Commissariat A L'energie Atomique; Hôpital Raymond Poincaré; IRMage; INSERM U1216 Grenoble Institut des Neurosciences; Locked-in syndrome association; CEA-Clinatec
• Investigators: Principal Investigator: Stephan CHABARDES, University Hospital, Grenoble

Study record dates

Study Major Dates

• Study Start (Estimated): October 10, 2026
• Primary Completion (Estimated): January 30, 2031
• Study Completion (Estimated): September 30, 2031

Study Registration Dates

• First Submitted: June 2, 2026
• First Submitted That Met QC Criteria: July 7, 2026
• First Posted (Actual): July 13, 2026

Study Record Updates

• Last Update Posted (Actual): July 13, 2026
• Last Update Submitted That Met QC Criteria: July 7, 2026
• Last Verified: July 1, 2026

More Information

Terms related to this study

• Keywords: Locked in syndrom, Speech disorders, Brain-computer interface, BCI, speech rehabilitation
• Additional Relevant MeSH Terms: Neurologic Manifestations; Central Nervous System Diseases; Nervous System Diseases; Neuromuscular Diseases; Metabolic Diseases; Neurobehavioral Manifestations; Neurodegenerative Diseases; Spinal Cord Diseases; TDP-43 Proteinopathies; Proteostasis Deficiencies; Motor Neuron Disease; Communication Disorders; Paralysis; Language Disorders; Quadriplegia; Pathological Conditions, Signs and Symptoms; Nutritional and Metabolic Diseases; Signs and Symptoms; Locked-In Syndrome; Amyotrophic Lateral Sclerosis; Speech Disorders
• Other Study ID Numbers: 38RC23-0266

Drug and device information, study documents

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