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Human Body Version 2.0
Researchers at MIT and Harvard are developing neural
implants to replace damaged retinas. [4] There are brain
implants for Parkinson’s patients that communicate directly
with the ventral posterior nucleus and subthalmic nucleus
regions of the brain to reverse the most devastating symptoms
of this disease. An implant for people with cerebral palsy and
multiple sclerosis communicates with the ventral lateral thala-
mus and has been effective in controlling tremors. “Rather
than treat the brain like soup, adding chemicals that enhance
or suppress certain neurotransmitters,” says Rick Trosch, an
American physician helping to pioneer these therapies, “we’re
now treating it like circuitry.”
A variety of techniques are being developed to provide
the communications bridge between the wet analog world
of biological information processing and digital electronics.
Researchers at Germany’s Max Planck Institute have devel-
oped noninvasive devices that can communicate with neurons
in both directions. [5] They demonstrated their ‘neuron tran-
sistor’ by controlling the movements of a living leech from
a personal computer. Similar technology has been used to
reconnect leech neurons and to coax them to perform simple
logical and arithmetic problems. Scientists are now experi-
menting with a new design called ‘quantum dots’, which uses
tiny crystals of semiconductor material to connect electronic
devices with neurons. [6]
These developments provide the promise of reconnecting
broken neural pathways for people with nerve damage and
spinal cord injuries. It has long been thought that recreat-
ing these pathways would only be feasible for recently injured
patients because nerves gradually deteriorate when unused.
A recent discovery, however, shows the feasibility of a neu-
roprosthetic system for patients with long-standing spinal
cord injuries. Researchers at the University of Utah asked a
group of long-term quadriplegic patients to move their limbs