Inner ear's energy can work like a battery, can power tiny devices .
For the first time, an electrical device has been powered by the ear alone. The team behind he technology used a natural electrochemical gradient in cells with the inner ear of a guinea pig to power a wireless transmitter for u to five hours. The technique could one day provide an autonomous power source to the brain and cochlear implants, says Tina Stankovic, an auditory neuroscientist at Harvard University Medical School in Boston, Massachusetts.
Nerve cells use the movement of positively charged sodium and potassium ion across a membrane to create an electrochemical gradient that drives neural signals. SOme cells in the cochlear have the same kind of gradient, which is used to convert the mechanical force of the vibrating eardrum into electrical signals that brain can understand.