The use of brain-machine interfaces, and more generally the use of digital neurotechnologies, gives rise to major ethical questions. The CCNE (National Consultative Ethics Committee) and the CNPEN (National Pilot Committee for Digital Ethics) recently published a joint report on the subject.
Neurotechnologies currently enable the observation and modulation of cerebral activity, opening up new prospects for the diagnosis and treatment of neurological and psychiatric diseases. Such innovations however represent major challenges, in particular regarding data protection, enlightened consent and the risk of abuse in medical applications and beyond.
What are we talking about? A few definitions
1. Neurotechnologies
According to the UNESCO definition, "Neurotechnologies refer to the apparatus, systems and procedures – including both the hardware and software – which enable direct measurement of the nervous system, to access it, monitor it, analyse it, and predict its activity or modulate it, in order to understand, influence, restore or anticipate its structure, its activity and its functions".
The development of such technologies is justified by medical progress and the progress in digital sciences. We better understand the cerebral functions and we are now capable of producing miniaturised interfaces, analysing cerebral activity data using AI (artificial intelligence).
2. Brain-machine interface
A Brain-Machine Interface (BMI) is a direct link system between a brain and a computer. The interface generally consists of one or more electrodes which pick up a signal which is then transmitted to the computer which interprets the signal and triggers a response. The device enables an individual to undertake tasks without any action by the peripheral nerves and muscles.
3. Neural data
Neural data are the qualitative and quantitative data concerning the structure, the activity and the functioning of the nervous system, collected thanks to neurotechnologies. They consist of the most direct measurements or observations of the state of the nervous system, including several states which can be correlated to mental states.
Major development prospects
In recent years, a few spectacular advances have provided a showcase to the work on BMI. In the medical field, neuroprostheses can be mentioned. For several decades, cochlear implants have successfully treated extreme deafness. Work is progressing on vision, but according to the report, "The results are still limited as the difficulties are greater than for hearing".
Devices are also available to replace deficient motor control. In order to counter a paralysis, the interface decodes the activity in a region of the brain and a machine is activated to help the person to walk, or to produce a synthetic voice. This type of development enables those suffering from locked-in syndrome, or lateral amyotrophic sclerosis (LAS) to communicate.
Neurotechnologies include both "invasive" devices, i.e. with a component which penetrates inside the body by crossing the skin barrier, and non-invasive devices. As indicated in the report, "The general idea is that the disease is responsible for the disfunction of several cerebral regions and their connections. Cerebral stimulation, by targeting one of these regions, aims to re-establish the overall equilibrium and so diminish or eradicate certain symptoms". Convincing successes have been achieved with patients suffering from Parkinson's disease.
Non-invasive devices, which are less hazardous, have been tested for chronic pain and for psychiatric disorders. The document notes that "Certain beneficial effects, when they are observed, appear to be remanent, i.e. to persist between or after therapeutic sessions ". However, the results remain to be confirmed. According to the report, "As with all medical treatments, confirmation of the results requires their reproduction in several rigorously controlled studies, covering sufficient cases, providing convergent results, which is often far from being the case".
The report also notes that recent advances, although significant, remain far removed from the fears or hopes announced by some.
"The devices available or expected in the near future will probably not allow "reading thoughts" according to the usual meaning of the term. The new possibilities, as extraordinary as they may seem, still remain very limited. Despite superficial similarities, the human brain does not operate like a computer and it is not foreseeable in the current state of knowledge to connect directly to a digital system in order to "download" memory or thoughts or to transmit complex information."
Technologies extending beyond the medical field
Beyond medical uses, these new technologies are attracting interest in numerous other fields: leisure, education, sport, and for certain professions, for example the military. The document recalls that- "In France, the use of implanted (invasive) BMI in such environments is not conceivable and that current prospects only concern non-invasive portable devices. Non-invasive cerebral stimulation is already being used outside the medical field". Certain nations have already started to use this type.
According to the report, "Such techniques benefit in particular the professions in which there is a high level of vigilance and attention and where the consequences of errors can be serious (aircraft pilots, vehicle drivers, dangerous machine operators, surgeons, etc.). The Brain-Machine interfaces which are promoted aim to detect undesirable overall cognitive states (cognitive overload, diminished concentration, drowsiness etc.".
The use of lightweight non-invasive devices (headsets, goggles etc.) for gaming purposes is commonplace: video games, "metaverse" or virtual reality… A market is also appearing to propose devices aimed at "well-being", for example headsets and sensors to "favour" concentration, or sleep. The report includes a warning about such uses: "They raise questions concerning their undesirable effects, which are all the more worrying in that they concern apparently commonplace and attractive uses, potentially aimed at a broad customer base, and which avoid any prospective evaluation".
The ethical issues raised by such technologies
These technologies enable both the measurement and modulation of cerebral activity. The ability to modify cerebral activity raises the issue of the possibility of "taking control" of a person. Moreover, the activity measurements are sufficiently precise to enable identification.
"It is possible to identify subjects by reconstructing their face from images obtained through cerebral magnetic resonance imagery (MRI) then using facial recognition techniques and public data bases".
The question of privacy intrusion, and identification as a further means of public surveillance is of concern. Indeed, the more devices are proposed and distributed to the general public, the more data will be picked up, stored and potentially made available to companies or the State. The report notes that "currently, the identifying nature of neural data collected by lightweight non-invasive brain-machine interfaces has not been demonstrated, but must be considered as a possibility according to the development of analysis methods". Although the danger may not be immediate, it must nevertheless be considered in the ethical recommendations.
For those reasons, the joint report includes a series of recommendations.
- Train, inform, and include the questions regarding neurotechnologies in the bioethics convention, and the coming revisions to the law.
- Treat neural data as sensitive personal and potentially identifying data. Safety mechanisms must therefore be included for the storage of such data and enlightened consent must be obtained for their processing in the context of medical applications.
- For non-medical uses, the CCNE and CCNEN have called for a ban on invasive devices, monitoring of non-invasive devices, and wish to control their use for professional applications. For example, the report suggests that "the use of neural data for the recruitment, evaluation, promotion, sanction or firing of employees should be considered as discriminatory".
- Whenever a device is liable to modify behaviour, the report recommends that "For each type of digital neurotechnology liable to be commercialised, it is essential to determine the consequences of deprivation of the device, in particular following extended use".
- Finally, the report recommends heightened protection for minors, whose brain is still under development: "Other than for research or medical purposes, to prohibit the use of digital neurotechnologies on children or adolescents, including in the educational and leisure fields".
Humanity has been developing tools since the very beginnings of time. Such tools in turn have moulded human intelligence. Ensuring a responsible use of such tools for the general good is a new challenge at each new discovery. Regarding neurotechnologies, the repair of patients without seeking to modify or "enhance" them artificially demands discernment, political will, and education of all.
In January 2025, the Biomedicine Agency was entrusted with the Development Charter in charge of Neurotechnologies, a document initiated by the Ministry for Higher Education and Research in 2022 and aimed at reconciling scientific advances, ethics and the protection of human rights.