Researchers at Georgetown University Medical Center revealed an interesting fact about infants’ brains through a clinical study. The study found that in babies who suffered a major stroke in the left hemisphere days after birth, their brain was “plastic” enough for the right hemisphere to acquire language abilities of the left hemisphere. Additionally, the right hemisphere also maintained its own language abilities.
The left hemisphere normally processes sentences and understands words as we speak. Whereas the right hemisphere processes the emotions of the voice.
“What happens when one of the hemispheres is injured at birth?”
The findings are in PNAS for October 10th, 2022.
The developmental period and pregnancy were normal for most participants. However, each of them had a significant stroke around birth, producing debilitating outcomes in adults. Furthermore, in infants, strokes are very rare, but it happens in one out of every four thousand births.
Elissa Newport, the first author of the study said,
Our most important conclusion is that plasticity in the brain, specifically the ability to reorganize language to the opposite side of the brain, is definitely possible early in life
She further added,
However, this early plasticity for language is restricted to one brain region. The brain is not able to reorganize injured functions just anywhere, as more dramatic reorganization is not possible even in early life. This gives us great insights into the regions we might be able to focus on for potential breakthroughs in developing techniques for recovery in adults as well.
Furthermore, the investigators recruited participants from across the US who suffered a large stroke in the cortex region of their left hemispheres during birth time. The participants’ siblings who were closer in age were also evaluated for comparison. Additionally, MRI scans were also done to reveal the areas of the brain involved in sentence comprehension.
The healthy siblings completed the language tasks without any issues. However, the only difference was that the siblings processed the language on the left side of the brain. Whereas the stroke participants showed a rare language activation pattern in the right hemisphere despite the extensive left hemisphere damage. Furthermore, only small stroke participants did not show any dominant activity in the right hemisphere.
Newport said,
It is also notable that many years after their strokes, our participants are all such highly functioning adults. Some are honour students and others are working toward or have gotten their master’s degrees
Their achievements are remarkable, especially since some of their parents had been told when they were born that their strokes would produce life-long impairments.
