Scientists have discovered that the brains of people who have been deaf since birth use the hearing area to help process visual information.
A study led by scientists from revealed new data on brain reorganization in people deaf from birth that could “help refine high-tech devices” such as cochlear implants.
The UC stated that the opens new lines of investigation into how the brain processes sensory information in the absence of a senseby suggesting that brain activity reduction responses also play an active role in this processing.
“The new clues released by the study could help refine high-tech devices that are used to restore hearing, such as cochlear implants.”
Research led by the UC team of scientists showed that the auditory cortex in people with congenital deafness responds to visual stimuli also through neuronal deactivationand not just by activation, as previously thought.
“That is, in people who have been deaf since birth, the region of the brain that processes auditory information also uses a pattern of reduced activity to represent visual information. This suggests that the brain uses a variety of strategies to adapt to the absence of meaning – in this case, using the auditory cortex to process visual information.”
Although brain plasticity (the brain’s ability to reorganize its functioning in response to sensory deprivation) is a widely studied topic in neuroscience, there is still a lot of information to be known or clarified.
“In previous studies it was noticed how visual information reached the auditory cortex of congenitally deaf people. In this study, we analyzed how this information is organized”, he explained.
Methodology and visual organization in the brain
Scientists used “functional magnetic resonance imaging to compare the brain activity of adults deaf since birth and adults with hearing when faced with visual stimuli” and subsequently applied “an advanced technique, called population receptive field modeling, to analyze the characteristics of the representation of visual information in the brain.”
FPCEUC researcher and study co-author Zohar Tal said that, “in deaf participants, the auditory cortex presents spatially organized visual responses – as happens in the visual cortex, called retinotopic organization – and this sensory reorganization does not only happen through activations, but also through mechanisms of neuronal suppression or deactivation, which can be equally informative.”
This research also had the participation of the professor and researcher at FPCEUC and director of the Proaction Laband the collaboration of scientists from China and the United Kingdom.
