Dyslexia is typically seen as a reading disorder, but
many dyslexics are also known to have trouble processing sensory information. Research
now reveals that dyslexics find it especially difficult to shift their attention between visual and audio stimuli. This suggests that brain training with action video
games could actually improve dyslexics’ literacy skills.
Dyslexia isn’t just a single, narrowly defined disorder —
there are various types and symptoms of dyslexia. For example, some people with
dyslexia have audio or visual deficits. And sometimes, those deficits stand
apart from comprehending letters, words and their related sounds, explained
Vanessa Harrar, a psychologist who studies multisensory integration at the University
of Oxford in the U.K.
https://gizmodo.com/learning-klingon-helps-man-confront-his-dyslexia-5846742
What this often means is that these people will take longer
to process or understand visual or audio stimuli. Over a decade ago,
researchers suggested that the root of these problems has
to do with attention. “In general, dyslexics have a kind of shifting
delay when they turn their attention from one stimulus to another,” Harrar
told io9. This is called “sluggish attentional shifting.”
Knowing that dyslexics have these attention-related, sensory
deficits, Harrar and her colleagues initially wanted to come up with a kind of
test to “capture all of the dyslexics.” “[The disorder] presents
itself as so many different symptoms,” Harrar said. “We were looking
for some kind of multisensory test that would make it easier to know who is
dyslexic.” The team decided to focus on reaction time tasks.
Switching Between the Senses
The researchers sat dyslexics and non-dyslexics in front of
a computer, and then presented them with different stimuli. Whenever the
participants heard a sound, saw a flash or experienced both cues together
coming from the computer, they had to press a button as quickly as possible.
The team recorded and analyzed the participants’ speeds for numerous trials.
The participants’ performance on the individual tests were
more or less what was expected, but the real surprise came when the researchers
compared the reaction times across trials. “The differences we found [between
dyslexics and non-dyslexics] involved switches between modalities,” Harrar
said, referring to the cases where the participants faced one type of sensory
trial followed by a different type. “Our main finding is that is more difficult for
dyslexics to go from visual to audio stimuli.”
Specifically, the dyslexics’ reaction times were, on average, 18 milliseconds
slower when a visual trial was preceded by an auditory or multisensory trial than
when a visual trial was preceded by another visual trial. But it was 35
milliseconds slower when an auditory trial was preceded by a visual trial than when
an auditory trial was preceded by another auditory trial.
That is, the dyslexics showed sluggish attentional shifting,
but only when turning their attention from their sense of sight to their sense
of hearing. This suggests that dyslexics could learn “audio-visual phonological
associations” faster if they hear how something is pronounced before
seeing the corresponding letter or word.
The results of the research differ from previous, similar
studies, but Harrar stressed that those studies didn’t control for an
additional, important variable: Localization. In Harrar’s work, the flash of
light and the sound both came from the direction of the computer screen. But in
previous studies, researchers had the participants wear headsets, so the sound
came from a different area (their head) than the flash of light. “They
were not only switching senses, but also location,” Harrar said.
Brain Training With Video Games
The new study suggests that dyslexics are more focused on
vision, and it is more difficult for them to shift their attention away from a
visual stimulus — a finding that actually fits in with what scientists
know about the attention aspect of dyslexia, Harrar said. When you read a line
of text, your eyes move after your attention does. “You sort of shoot a
spotlight to the next word, and then your eyes move,” she said. “With
dyslexics, their spotlight doesn’t move, or it doesn’t move as quickly or as
far.”
The idea, then, is that if you can train or improve their
attention system, then everything else will follow. And, in fact, this is
exactly what recent research has found.
Last year, scientists reported that playing
action video games helps dyslexic children read better. These games have a
lot going on, requiring you to react quickly to the demands of the game. “It
trains them to move their eyes and shift their attention quickly, so the basic
attention deficits naturally fix themselves,” Harrar said. “Then when
it comes to reading, suddenly they are reading much faster.”
Harrar and her colleagues believe that it’s possible to
make action video games even better for some dyslexics. Instead of having the
game loaded with constant multisensory stimuli, you could design a game that
purposefully switches back and forth between visual and audio stimuli. This
will, presumably, help dyslexics train their ability to switch from one sense
to another.
https://gizmodo.com/watch-nick-harkaway-explain-why-video-games-will-save-t-1472722644
The researchers now want to repeat their work, but keep a
keen eye on the type of deficits the dyslexic participants have. In their
study, they didn’t look to see if their participants had mainly auditory or visual
deficits. It may be the case that their sample was made up of dyslexics with
mostly visual deficients, and that dyslexics with auditory deficits actually
have more trouble switching from sounds to sights.
Check out the study
over in the journal Current Biology.
Top image from Assassin’s Creed 4.
Inset image via Léa Gagnon; Micheline Gloin; Daphneé Harrar.
