Experimental TBI Study Finds Age-Dependent Paths to Seizures and Memory Loss

A Texas A&M University study suggests that age influences how the brain changes after traumatic brain injury (TBI), with younger and older laboratory models following distinct neurological trajectories during four months of monitoring.

Published in Experimental Neurology, the research examined neurological activity, cognition and brain structure after traumatic injury. The findings challenge the idea that younger brains simply recover better because of their greater capacity to adapt.

Younger models developed seizure-related changes more gradually. Electrical activity associated with epilepsy was higher, and seizure activity appeared later but increased over time, producing a substantially greater seizure burden during the study’s long-term phase. Post-traumatic epilepsy is a chronic seizure disorder that can emerge months or years after an injury.

Older models showed a different pattern. When seizure activity occurred, it generally appeared earlier and then stabilized at a more limited level. However, the older models displayed stronger evidence of persistent inflammation and abnormal circuit reorganization—changes the researchers considered relevant to memory problems and later dementia-like decline after brain injury.

Functional recovery also differed by age. Older models recovered motor function and coordination more quickly, while younger models continued to show problems with balance and coordination. Memory testing produced the opposite pattern: older models had greater difficulty retaining long-term memories, even when their initial learning appeared relatively intact. Younger models also developed cognitive deficits, but their memory decline was less pronounced.

The researchers found comparable levels of neuron loss in the two age groups, indicating that cell death alone did not account for the different outcomes. Instead, the results pointed to differences in how neural circuits reorganized and how inflammation persisted after the injury.

Senior author Samba Reddy, a neuroscience and experimental therapeutics professor at Texas A&M University, said the findings indicate that brain plasticity may have mixed consequences after injury. Adaptation may support recovery in some functions while also contributing to the formation of seizure-producing networks.

The study is preclinical: its conclusions came from laboratory models rather than human patients. It therefore does not establish that younger or older people will experience the same patterns, or that age-specific treatments are currently available. The researchers said the findings could help guide future work on strategies tailored to different long-term risks—such as seizure development in younger brains and inflammation, memory loss and cognitive decline in older brains.