Neuroscientists have discovered that the region of the brain responsible for processing visual information in individuals who can see creates a distinct connectivity pattern in those who are born blind. This pattern, found in the primary visual cortex, is as unique to each person as a fingerprint.
Researchers from Georgetown University have found that the area of the brain that processes visual data in sighted individuals develops a singular connectivity pattern in individuals who are born blind. They suggest that this pattern in the primary visual cortex is unique to each person, similar to a fingerprint.
For many years, it has been known that the visual cortex of people who are blind from birth can react to a variety of stimuli, such as touch, smell, sound localization, memory, and language. However, the absence of a clear connection among the tasks that activate the primary regions of the visual cortex has puzzled scientists. The recent study, led by Lenia Amaral, PhD, a postdoctoral researcher, and Ella Striem-Amit, PhD, the Edwin H. Richard and Elisabeth Richard von Matsch Assistant Professor of Neuroscience at Georgetown University’s School of Medicine, provides an insightful explanation: variances in how each person’s brain is organized.
“We do not observe this degree of variation in visual cortex connectivity among sighted individuals — the visual cortex usually has a relatively consistent structure,” stated Striem-Amit, who leads the Sensory and Motor Plasticity Lab at Georgetown. “In people born blind, the connectivity patterns differ widely, resembling individual fingerprints, and these patterns remain stable over time — to such an extent that we can identify individuals based solely on their connectivity pattern.”
The study involved a small group of individuals born blind who participated in multiple functional MRI scans over a period of two years. The researchers utilized a neuroimaging method to examine the network of neural connections within the brain.
“The visual cortex in individuals born blind exhibited extraordinary stability in its connectivity patterns throughout the study duration,” Amaral highlighted. “We found that these patterns did not significantly vary with different tasks, whether participants were identifying sounds, recognizing shapes, or simply at rest. Rather, these connectivity patterns were distinctive for each individual, remaining consistent over the two-year timeframe.”
Striem-Amit remarked that these results enhance our understanding of brain development. “Our research indicates that experiences after birth influence the diverse developmental paths of our brains, particularly for those growing up without vision. The brain’s plasticity allows for different developmental opportunities, potentially leading to various functions of the visual cortex among individuals born blind,” Striem-Amit noted.
The researchers suggest that recognizing each person’s unique connectivity could be crucial for crafting more effective rehabilitation and sight restoration strategies, customized based on their individual brain connectivity patterns.
The authors state that they have no personal financial interests linked to the study.
This research received financial support from grants from the National Institutes of Health NEI/OBSSR (R01EY034515) and contributions from the Edwin H. Richard and Elisabeth Richard von Matsch Distinguished Professorship in Neurological Disorders.
