Nav: Home

After blindness, the adult brain can learn to see again

October 25, 2016

More than 40 million people worldwide are blind, and many of them reach this condition after many years of slow and progressive retinal degeneration. The development of sophisticated prostheses or new light-responsive elements, aiming to replace the disrupted retinal function and to feed restored visual signals to the brain, has provided new hope. However, very little is known about whether the brain of blind people retains residual capacity to process restored or artificial visual inputs. A new study publishing 25 October in the open-access journal PLOS Biology by Elisa Castaldi and Maria Concetta Morrone from the University of Pisa, Italy, and colleagues investigates the brain's capability to process visual information after many years of total blindness, by studying patients affected by Retinitis Pigmentosa, a hereditary illness of the retina that gradually leads to complete blindness.

The perceptual and brain responses of a group of patients were assessed before and after the implantation of a prosthetic implant that senses visual signals and transmits them to the brain by stimulating axons of retinal ganglion cells. Using functional magnetic resonance imaging, the researchers found that patients learned to recognize unusual visual stimuli, such as flashes of light, and that this ability correlated with increased brain activity. However, this change in brain activity, observed at both the thalamic and cortical level, took extensive training over a long period of time to become established: the more the patient practiced, the more their brain responded to visual stimuli, and the better they perceived the visual stimuli using the implant. In other words, the brain needs to learn to see again.

The results are important as they show that after the implantation of a prosthetic device the brain undergoes plastic changes to re-learn how to make use of the new artificial and probably aberrant visual signals. They demonstrate a residual plasticity of the sensory circuitry of the adult brain after many years of deprivation, which can be exploited in the development of new prosthetic implants.
-end-
In your coverage please use this URL to provide access to the freely available article in PLOS Biology: http://dx.doi.org/10.1371/journal.pbio.1002569

Citation: Castaldi E, Cicchini GM, Cinelli L, Biagi L, Rizzo S, Morrone MC (2016) Visual BOLD Response in Late Blind Subjects with Argus II Retinal Prosthesis. PLoS Biol 14(10): e1002569. doi:10.1371/journal.pbio.1002569

Funding: This research was funded by the European Research Council under the European Union's Seventh Framework Programme (FPT/2007-2013) under grant agreement no. 338866 ECPLAIN (http://www.pisavisionlab.org/index.php/projects/ecsplain) and by the Fondazione Roma under the Grants for Biomedical Research: Retinitis Pigmentosa (RP)-Call for proposals 2013 (http://www.fondazioneroma.it/it/index.html, http://wf-fondazioneroma.cbim.it/), project title: "Cortical Plasticity in Retinitis Pigmentosa: an Integrated Study from Animal Models to Humans." MCM received both these grants. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.

Competing Interests: The authors have declared that no competing interests exist.

PLOS

Related Brain Activity Articles:

How dopamine drives brain activity
Using a specialized magnetic resonance imaging (MRI) sensor that can track dopamine levels, MIT neuroscientists have discovered how dopamine released deep within the brain influences distant brain regions.
Brain activity intensity drives need for sleep
The intensity of brain activity during the day, notwithstanding how long we've been awake, appears to increase our need for sleep, according to a new UCL study in zebrafish, published in Neuron.
Do babies like yawning? Evidence from brain activity
Contagious yawning is observed in many mammals, but there is no such report in human babies.
Understanding brain activity when you name what you see
Using complex statistical methods and fast measurement techniques, researchers found how the brain network comes up with the right word and enables us to say it.
Your brain activity can be used to measure how well you understand a concept
As students learn a new concept, measuring how well they grasp it has often depended on traditional paper and pencil tests.
Altered brain activity in antisocial teenagers
Teenage girls with problematic social behavior display reduced brain activity and weaker connectivity between the brain regions implicated in emotion regulation.
Gender impacts brain activity in alcoholics
Compared to alcoholic women, alcoholic men have more diminished brain activity in areas responsible for emotional processing (limbic regions including the amygdala and hippocampus), as well as memory and social processing (cortical regions including the superior frontal and supramarginal regions) among other functions.
Light, physical activity reduces brain aging
Incremental physical activity, even at light intensity, is associated with larger brain volume and healthy brain aging.
Measuring brain activity in milliseconds possible through new research
Researchers from King's College London, Harvard and INSERM-Paris have discovered a new way to measure brain function in milliseconds using magnetic resonance elastography (MRE).
Autism: Brain activity as a biomarker
Researchers from Jülich, Switzerland, France, the Netherlands, and the UK have discovered specific activity patterns in the brains of people with autism.
More Brain Activity News and Brain Activity Current Events

Trending Science News

Current Coronavirus (COVID-19) News

Top Science Podcasts

We have hand picked the top science podcasts of 2020.
Now Playing: TED Radio Hour

Listen Again: Reinvention
Change is hard, but it's also an opportunity to discover and reimagine what you thought you knew. From our economy, to music, to even ourselves–this hour TED speakers explore the power of reinvention. Guests include OK Go lead singer Damian Kulash Jr., former college gymnastics coach Valorie Kondos Field, Stockton Mayor Michael Tubbs, and entrepreneur Nick Hanauer.
Now Playing: Science for the People

#562 Superbug to Bedside
By now we're all good and scared about antibiotic resistance, one of the many things coming to get us all. But there's good news, sort of. News antibiotics are coming out! How do they get tested? What does that kind of a trial look like and how does it happen? Host Bethany Brookeshire talks with Matt McCarthy, author of "Superbugs: The Race to Stop an Epidemic", about the ins and outs of testing a new antibiotic in the hospital.
Now Playing: Radiolab

Dispatch 6: Strange Times
Covid has disrupted the most basic routines of our days and nights. But in the middle of a conversation about how to fight the virus, we find a place impervious to the stalled plans and frenetic demands of the outside world. It's a very different kind of front line, where urgent work means moving slow, and time is marked out in tiny pre-planned steps. Then, on a walk through the woods, we consider how the tempo of our lives affects our minds and discover how the beats of biology shape our bodies. This episode was produced with help from Molly Webster and Tracie Hunte. Support Radiolab today at Radiolab.org/donate.