Thought control

Scientists at the University of Pennsylvania School of Medicine have described the basis for developing a biological interface that could link a patient’s nervous system to a thought-driven artificial limb.

Their conceptual framework - which brings together years of spinal-cord injury research - is published in the January issue of Neurosurgery.

‘We’re at a junction now of developing a new approach for a brain-machine interface,’ said senior author Douglas H Smith, MD, Professor of Neurosurgery and Director of the Center for Brain Injury and Repair at Penn. ‘The nervous system will certainly rebel if you place hard or sharp electrodes into it to record signals. However, the nervous system can be tricked to accept an interface letting it do what it likes - assimilating new nerve cells into its own network.’

To develop the next generation of prosthetics the idea is to use regions of undamaged nervous tissue to provide command signals to drive a device, such as an artificial limb. The challenge is for a prosthesis to perform naturally, relaying two-way communication with the patient’s brain. For example, the patient’s thoughts could convert nerve signals into movements of a prosthetic, while sensory stimuli, such as temperature or pressure provides feedback to adapt the movements.