Applying Psychology
in the 21st Century
Mind over Cursor: Harnessing
Brainpower to Improve Lives
Hans-Peter Salzmann, a lawyer suffering
from Lou Gehrig’s disease, was locked
within his own body. Paralyzed by the dis-
ease and unable to eat, speak, or even
breathe on his own, he had to rely on a res-
pirator and a feeding tube to survive. Al-
though
his mind functioned normally, he
was unable to communicate with the out-
side world.
All that changed, however, after Salz-
mann obtained an experimental device that
allows brain waves to be translated into
written communication. Using EEG scan-
ning techniques that react to the pattern of
brain waves originating in the brain, Salz-
mann learned to boost and curtail certain
types of brain waves. After hundreds of
hours of practice,
he was able to select let-
ters that appear on a video screen. By
stringing letters together, he could spell out
messages. The process, which makes use of
brain waves called “slow cortical poten-
tials,” permitted Salzmann to communicate
effectively for the fi rst time in years. Al-
though the method is slow and tedious—
Salzmann can produce only about two
characters per minute—it holds great
promise for people with spinal cord injuries
and diseases that have left them paralyzed
(Neumann & Birbaumer, 2004; Pollack,
2006; Hatsopoulos &
Donoghue, 2009).
Neuroscience researchers are making re-
markable progress at developing this tech-
nology of thought-based interfaces. It’s not
ready to be put into widespread use, but
recent discoveries show how rapidly the
technology is developing. In one extraordi-
nary experiment, researchers implanted
freckle-sized electrodes onto the brains of
two monkeys at the motor cortex—the re-
gion of the brain responsible for voluntary
muscle movement. Each electrode con-
nected with 100 individual neurons in this
region. A computer
wired to the electrodes
interpreted the signals coming from these
neurons and used the information to direct
the movement of a mechanical arm while
the monkeys’ own arms were restrained
(Velliste et al., 2008).
The monkeys were initially “trained”
in the manipulation of the arm, using joy-
sticks at fi rst and then using the brain in-
terface with additional computer guidance
(somewhat like using training wheels
while learning to ride a bicycle). Within
days, the monkeys were operating the
arm using just
their thoughts with no ad-
ditional help. They sat in a chair and used
the arm to reach out and grab treats such
as grapes and marshmallows and bring
them to their mouths. This task required
them not only to move the arm through
space but also to manipulate the grip on
its end to seize the food and then to re-
lease it into their mouths.
While this much of a successful accom-
plishment was extraordinary by itself, the
progress didn’t stop there. The monkeys
actually proceeded to show the scientists a
new trick
or two by becoming adept
enough with the brain interface to impro-
vise entirely unanticipated manipulations
of the mechanical arm, such as using it to
push food into their mouths as if it were
their own hand. This ability is an impor-
tant step forward, as any practical device
for assisting the disabled would have to be
able to be used in inventive ways in order
to provide for their unique needs in a natu-
ral way. No
computer program alone can
anticipate every possible movement that
might be necessary, but the monkeys
showed that they could adapt the device to
serve their own goals (Carey, 2008; Velliste
et al., 2008).
Many hurdles remain before paralyzed
people will be using thought-controlled
devices routinely, particularly in terms of
the need for stable electrodes, wireless
communication,
and portable translating
computers. But achievements such as this
give researchers hope that they are close to
overcoming the remaining challenges such
that one day—perhaps sooner than one
might expect—their seemingly wild dream
of giving new mobility to paralyzed people
will be realized (Stix, 2008).
• Why is it so important to develop a complex and very expensive means of com-
munication for the relatively small number of people who are living with locked-in
syndrome?
Do'stlaringiz bilan baham: