A single flexible fibre, thinner than a human hair, has been successfully used to deliver a combination of optical, electrical, and chemical signals to the brain for the first time.
A collaboration of material scientists, chemists and biologists made the breakthrough which was made possible by the development of conductive ‘wires’ that maintained required flexibility while carrying electrical signals.
The development could make it possible to leave implants in place and have them retain their functions over much longer periods than is currently possible with typical stiff, metallic fibres.
Scientists compressed layers of polyethylene sprinkled with graphite flakes to make the material. This method increased the conductivity of the polymer by a factor of four or five, which enabled the team to reduce the size of the electrodes by the same amount.
The research team included members of MIT’s Research Laboratory of Electronics, Department of Electrical Engineering and Computer Science, McGovern Institute for Brain Research, Department of Chemical Engineering, and Department of Mechanical Engineering, as well as researchers at Tohuku University in Japan.
The results of a study on the subject have been reported in the journal Nature Neuroscience.