IEEE Spectrum September, 2008 - 9

Virtual-Reality Test
Reveals Hidden
Concussion Damage
A technology that can tell when athletes are
ready to get back in the game

A

utumn is upon us,
and in the United
States, so is football
season. The players, who
deliver jarring hits to one
another that often equal
the force of car wrecks,
are lionized for the ability
to, in the words of an old
watch commercial, "take a
licking and keep on ticking."
But concussions are not
uncommon, and new research
shows that even when players
are symptom-free and have
passed a battery of cognitivefunction tests, their brains
may not have completely
recovered and may still be
vulnerable to further injury.
An ongoing study at
Pennsylvania State University aims to create a reliable
electroencephalography
system for judging whether
an athlete should get back
in the game, stay on the
sidelines, or call it quits.
In an early round of the
study, to be published in
IEEE Transactions on Neural
Systems and Rehabilitation
Engineering, 61 football, rugby,
and soccer players at Penn
State (male and female) were
examined; 30 of them were
chosen because they had
suffered concussions 30 days
prior to participating in the
study but had been cleared
for a full return to their sports.
14

Each subject was connected
to an electroencephalograph
via 19 electrodes attached to
his or her scalp and earlobes
and was asked to stand on
a platform studded with
sensors that recorded shifts
in pressure distribution at
the bottom of the feet. The
platform was surrounded
on three sides by video
screens that created a visually
immersive environment.
A computer running
a proprietary algorithm
recorded and synchronized
the subjects' physical and
neurological responses to
virtual-reality graphics. The
graphics were designed to
give participants the sense
that they were involved in
some situation that provokes a
physical response-say, riding
a roller coaster or participating
in a snowball fight.
The control group, made
up of players who had not
suffered concussions, mostly
did what was expected
when presented with virtual
situations that called for
complicated, coordinated
responses using multiple
body parts, and their brainwave patterns were ordinary.
Using the control data, the
system became increasingly
adept at identifying
previously concussed athletes,
who exhibited delayed

NA * Ieee Spectrum * September 2008

VIrTUAL ExAmInATIon: To assess athletes' injuries, scientists
measure motion and brain waves in response to virtual situations.
photo: eleNA slobouNoV

reaction times and abnormal
physical reactions like using
too little or too much force.
Nearly 97 percent of the time,
these abnormalities in motor
coordination corresponded
to detectable differences in
the athletes' brain waves
compared with baseline
readings taken before the start
of their competitive seasons.
According to research
associate Richard L.
Tutwiler, the Penn State
researchers are refining the
technique and gathering a
pool of data they think will
be large enough to yield a
reliable brain assessment
tool within two years. "The
hope is that we can then
make a portable unit that
can begin taking readings
right after a player gets off
the field," he says.
Stefan Duma, director
of Virginia Polytechnic
University's Center for
Injury Biomechanics and the
lead researcher on the Head
Impact Telemetry program

(HIT), applauds the Penn
State researchers' efforts.
The HIT system, developed
by researchers at Simbex,
of Lebanon, N.H., and at
Virginia Tech and Brown
universities, uses helmetmounted sensors to measure
the force of collisions. It then
alerts coaches and trainers
to those collisions likely to
have resulted in concussions,
based on data from more
than 30 000 impacts. [See
"Helmets Sense the Hard
Knocks," IEEE Spectrum,
October 2007.]
Jeffrey Chu, Simbex's
director of engineering, says
that Penn State's test and HIT
would be complementary
technologies. "HIT gives
sideline staff a powerful
tool by putting the focus
on players likely to have
suffered a brain injury," says
Chu. "A device based on EEG
or other assessment tools
would pick up from there,
determining the extent of the
damage."
-Willie D. Jones
www.SPEcTrUm.iEEE.orG
http://www.SPEcTrUm.iEEE.orG
Table of Contents for the Digital Edition of IEEE Spectrum September, 2008
