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FutureTech: Gerald Loeb

 Engineering the Future: Gerald Loeb
Bionics is the word Hollywood invented to explain “The Six Million Dollar Man” in the 1970s. It finally became respectable in the 1990s as sophisticated neural prosthetic devices, such as cochlear implants for the deaf, started to achieve real success with large numbers of patients.
BIONs™ — injectable neurostimulation devices about as big as a grain of rice — are Gerald Loeb’s technology focus now. The devices can transmit electrical signals into the peripheral nervous system to help people who suffer from a wide variety of neurological conditions, such as paralysis or incontinence. An M.D. and professor of biomedical engineering in the USC Alfred Mann Institute for Biomedical Engineering, Loeb has been working on bionic devices for many years.
“BIONs are intended primarily for paralyzed muscles, but there are many dysfunctions that occur in people who have lost the ability to control their muscles,” he says. “The idea behind this technology is to restore the electrical signals that are missing.”
During the 1990s, Loeb worked with Advanced Bionics Corp. in Sylmar, CA to commercialize the first truly multichannel cochlear implant. It was based on work he did in the 1970s with a team at UC San Francisco. Other neural prostheses are starting to enter the market in the U.S., he says, noting that biomedical devices typically have long development cycles — at least five to 10 years — before they can be commercialized.
Right now, the BION is being used in research to relieve complications of stroke, such as shoulder pain and hand contractions. The long-term goal is to create functional movement in a paralyzed arm. The tricky part is building in continuous control, using sensors, so that the device will be able to move a limb relatively smoothly and continuously rather than in spastic jerks.
“That requires designing a pattern of signals to stimulate the muscles continuously, which means that we have to mimic not just the electrical stimulation to activate the muscle but the hundreds of sensors that muscles normally have built into them to send information back to the spinal cord,” Loeb says.
A daunting task, but Loeb is busy incorporating movement sensors into the bionic devices. The devices will transmit the data to an external controller, which will then adjust the level of stimulation, acting just as the spinal cord and brain act to adjust muscle activation in healthy people.