The nonprofit House Ear Institutein Los Angeles is working on digital hearing aids that put sound directly into the brain. Nearly a dozen procedures that involve penetrating the surface of the cochlear nucleus right into the brain. Researchers hope the auditory brainstem implant will be ready for use in people with residual hearing in another 5 years. While analog hearing aids amplify all sound, digital can be nuanced to be more selective. Tiny computers can screen out noise and amplify pertinent sounds.