About 1 in 10 babies in the U.S. is born prematurely, according to the National Institutes of Health. Premature babies are born having had insufficient time to develop and are prone to many health risks. Among these risks is the possibility of suffering serious brain damage. This damage is known as “perinatal brain injury,” or PBI, and can have lasting effects into adulthood. Children with PBI struggle academically and score lower on IQ tests as adults. Specifically, PBI affects a process called “working memory.” Working memory allows the brain to process both new information and stored memories. It helps us make sense of the world, is essential to academic success, and is indispensable in everyday life. Treatments are being developed for people who have suffered PBI so that they may avoid these deficiencies. A recent study conducted by King’s College London and collaborators took a significant step toward achieving this goal.
The King’s College study examined the process the brain undergoes in recovering from an injury. By better understanding the steps the brain takes toward healing, the researchers hoped to learn how to promote recovery in people affected by PBI. Before beginning their study, the researchers first reviewed research on how the brain recovers from strokes. These studies have been instrumental in our learning how the brain heals and have been successfully applied in stroke rehabilitation programs. These programs take advantage of our brain’s inbuilt rehabilitation system, a process known as “neuroplasticity.” Neuroplasticity essentially enables our brains to rewire themselves over time. This process is important to basic brain development, learning, and memory. In the event of an injury, neuroplasticity allows the brain to reorganize and regain its ability to function. Similar to a company restructuring after a downsizing, the brain will restructure itself to compensate for its injured areas.
In light of this information on neuroplasticity, the King’s College study looked for signs of neuroplasticity in people who had suffered PBI. The study used fMRI and tractography technology to compare the brains of adults who had suffered PBI to healthy controls. The researchers hypothesized that the PBI group would show signs of brain reorganization in response to the damage they had sustained as infants. They predicted that the extent of this reorganization would correlate directly to the extent of the damage. They looked specifically at damage to a structure known as the “dorsal cingulum tract.” This tract acts as an important connection between the brain areas involved in working memory. Both the tract and working memory are negatively affected by PBI, making it a fitting focus for the King’s College study.
The King’s College researchers examined the brain structure of their participants and detailed any damages they observed, particularly in the dorsal cingulum tract. They then tested each participant’s working memory and monitored which brain areas became activated. In analyzing the data, the researchers found the PBI group had different brain structure and different patterns of brain activity than the controls. As predicted, adults that had suffered PBI had dorsal cingulum tracts of smaller volume and showed less activation in brain areas typically associated with working memory. One might think that these differences would cause the PBI group to perform poorly on the working memory test. On the contrary, the results revealed that the group scored as well on the working memory test as the controls. How is this possible?
The answer lies in neuroplasticity. The brains of people who suffer PBI may sustain lasting damage, but their intact, healthy brain structures work overtime to compensate for it. Over time, these healthy structures can correct for lost function. In the King’s College study, a specific brain area became active in the PBI group that did not in the controls. This area was found to be more active the smaller a participant’s dorsal cingulum tract was. Furthermore, more activation in this area also predicted better performance on the working memory test. This brain area is known as the “perisylvian cortex,” and these results suggest that it is crucial to the maintenance of working memory in the event of injury.
The King’s College study provided the first evidence of neuroplasticity following perinatal brain injury. It has established a starting point for developing better treatment for babies affected by PBI. The results of this study will help those babies into adulthood, along with others who suffer debilitating brain injuries. This study brings us closer to harnessing the power of neuroplasticity, our brain’s inbuilt rehabilitation program.