He led the cochlear implant team at UCSF, which transferred its technology to Advanced Bionics, and their version is the Clarion cochlear implant. He collaborated with Bill Jenkins and Gregg Recanzone to demonstrate sensory maps are labile into adulthood in animals performing operant sensory tasks. He collaborated with Paula Tallal, Bill Jenkins, and Steve Miller to form the company Scientific Learning. This was based on Fast ForWord software they co-invented that produces improvements in children's language skills that has been related to the magnitude of their temporal processing impairments prior to training.