people practiced finger movements with their right hand while watching
their left hand on 3D virtual reality headsets, they could use their
left hand more efficiently after the exercise, suggested researchers at Tel-Aviv University. The work, appearing
December 13 in Cell Reports, provides a new strategy to improve physical therapy for people with limited strength in their hands.
"We are tricking the brain," says lead author Roy Mukamel, a
professor of psychology at Tel Aviv University in Israel. "This entire
experiment ended up being a nice demonstration about how to combine
software engineering and neuroscience."
‘When people completed finger movements with their right hand while a 3D virtual reality headset showed their left hand moving, they could use their left hand more efficiently after the exercise.’
After completing baseline tests to assess the initial motor skills
of each hand, 53 participants strapped on virtual reality headsets,
which showed simulated versions of their hands. During the first
experiment, the participants completed a series of finger movements with
their right hand while the screen showed their virtual left hand moving
instead. Next, the participants put a motorized glove on their left
hand, which moved their fingers to match the motions of the right hand.
While this occurred, the headsets again showed their virtual left hand
moving instead of their right.
After analyzing the results, the researchers discovered that the
left hand's performance significantly improved (i.e., had more precise
movements in a faster amount of time) when the screen showed the left
hand. But the most notable improvements occurred when the virtual
reality screen showed the left hand moving while the motorized glove
moved the right hand in reality.
The researchers also used fMRI to track which brain structures were
activated during the experiments in 18 of the participants. The
scientists noted that one section of the brain, called the superior
parietal lobe, was activated in each person during training. They also
discovered that the level of activity in this brain region was
correlated to the level of improved performance in the left hand - the
more activity, the better the left hand performed.
"Technologically these experiments were a big challenge," says
Mukamel. "We manipulated what people see and combined it with the
passive movement of the hand to show that our hands can learn when
they're not moving under voluntary control."
The researchers are optimistic that this research can be applied to
patients in physical therapy programs who have lost the strength or
control of their hands. "We need to show a way to obtain
high-performance gains relative to other traditional types of
therapies," says Mukamel. "If we can train one hand without voluntarily
moving it and still show significant improvements in the motor skills of
that hand, then that's the ideal."