These images show how working memory activation patterns in patients with concussion differ by age.
Image credit: Radiological Society of North America
Dr. David Yen-Ting Chen, of Taipei Medical University in New Taipei City, Taiwan, and colleagues suggest the findings point to a need to treat older patients differently from younger patients following concussion or mild traumatic brain injury (MTBI).
MTBI is a significant public health problem. It represents around 75% of all traumatic brain injury cases, which, according to the Centers for Disease Control and Prevention (CDC), accounted for approximately 2.5 million emergency department visits, hospitalizations and deaths in the US in 2010.
After suffering a concussion, for example as a result of a blow to the head, people often report problems with working memory - the "mental jotting pad" where we temporarily hold information such as a phone number or name until we find somewhere more permanent to store it.
The researchers wanted to do the study because, while "old age has been recognized as an independent predictor of worse outcome from concussion," explains Dr. Chen, "most previous studies were performed on younger adults."
He and his colleagues note that mental tests and brain scans using computed tomography (CT) and conventional magnetic resonance imaging (MRI) generally fail to find anything wrong in MTBI patients. They note, however, that functional MRI (fMRI) is increasingly being used to assess MTBI symptoms.
Results suggest 'neural plasticity varies across different ages'
For their study, they used fMRI to evaluate the effect of age on working memory performance and functional activation in the brain after MTBI.
The researchers recruited 13 young adults aged 21-30 years and 13 older adults aged 51-68 years with MTBI and matched them with 26 controls without MTBI. All underwent first fMRI scans within 1 month of injury, and a follow-up scan 6 weeks later. The participants also underwent neuropsychological and working memory tests.
When they analyzed the results, the researchers found the younger patients had more initial activation (hyperactivation) than controls in two areas of the brain - the right precuneus and right inferior parietal gyrus - as they performed working memory tasks.
In contrast, the older patients showed less activation (hypoactivation) than controls in the right precuneus and right inferior frontal gyrus.
Also, while younger patients had significantly improved post-concussion symptoms at the follow-up, older patients showed little significant change between initial and follow-up exams, and their hypoactivation also persisted over the period.
Co-author Dr. Ying-Chi Tseng, of Taipei Medical University Shuang Ho Hospital, concludes:
"Taken together, these findings provide evidence for differential neural plasticity across different ages, with potential prognostic and therapeutic implications. The results suggest that MTBI might cause a more profound and lasting effect in older patients."
The team hopes the results will trigger a rethink in how to care for MTBI patients, with separate management strategies for different age groups following concussion.
Meanwhile, Medical News Today recently learned that a different use of an existing drug could help retrieve memory. A study published in the Journal of Neuroscience suggests a drug normally used to switch off genes that turn normal cells into cancerous ones could help people with dementia and Alzheimer's to regain the ability to make new memories.