A brain-controlled wheelchair designed to be operated reliably and safely over long periods of time via "shared control" technology. Device designer José del R. Millán says the wheelchair illustrates the future of intelligent neuroprostheses. (Image courtesy of José del R. Millán)

A brain-controlled wheelchair designed to be operated reliably and safely over long periods of time via “shared control” technology. Device designer José del R. Millán says the wheelchair illustrates the future of intelligent neuroprostheses. (Image courtesy of José del R. Millán)

Technology is emerging that decodes intention directly from a user’s brain. One of these devices is a brain-controlled wheelchair, currently under evaluation to determine whether it can operate under the rigors of daily use by individuals who are affected by varying types of disability.

The developer of this technology, José del R. Millán, a researcher based at the Swiss Federal Institute of Technology, Lausanne, Switzerland, describes the wheelchair, and a similar generation of neuroprestheses, as neuroprosthetic devices that decode brain signals via a brain-computer interface (BCI) to determine an action the user wants to take. Advanced robotics then do the work of the spinal cord in orchestrating the movement.

Millán revealed details about this technology at a presentation he made during the recent Cognitive Neuroscience Society (CNS) conference in San Francisco.

The BCI processes users’ intentions and decision-making primarily from the cerebral cortex. But, Millán notes that many elements of skilled movements are handled in the brainstem and spinal cord. By designing the intelligent device to control the lower-level movements in concert with the higher-level brain activity from the BCI, the neuroprostheses come closer to natural motor control. “We aim to interact with these neuroprostheses as if they were our new body, using the very same neural signals and principles that control our muscles,” Millán says.

As an example of the new types of neuroprostheses, Millán points to a brain-controlled wheelchair he and colleagues designed and published a paper about last year. Its users can drive it reliably and safely over long periods of time as a result of the shared control system reducing the cognitive workload. The wheelchairs are currently in the evaluation phase, to make sure that they will work in daily life conditions for a large number of people with motor disabilities.

A media release from the Cognitive Neuroscience Society reviewed Millán’s presentation, and points out that two of the biggest challenges for neuroprosthetics are finding new physical interfaces in addition to EEG that can operate permanently and over long periods of time, as well as providing rich sensory feedback. “This sensory information will make users feel the neuroprosthesis and the environment, what is essential to promote user’s agency and ownership of the prosthesis,” Millán says.

“The third major challenge is the one at the core of cognitive neuroscience: We must decode and integrate in the prosthetic control loop information about perceptual cognitive processes of the user that are crucial for volitional interaction,” he says. These processes include awareness to errors made by the device, anticipation of critical decision points, and lapses of attention.

[Source: Cognitive Neuroscience Society]