It is thought that individuals with spinal cord injuries (SCIs) are at greater risk of cognitive deficits similar to those seen in ageing. Such deficits include processing speed, the ability to learn and form new memories, and verbal fluency. This small study suggests that these deficits are reflected in brain activity when performing certain cognitive tasks.
The 30 study participants were part of a larger study of individuals who underwent optional neuroimaging studies at the Rocco Ortenzio Neuroimaging Center at the Kessler Foundation. There were 10 individuals with cervical SCI, 10 age-matched controls, and 10 healthy older individuals. The participants underwent traditional neuropsychological testing methods and processing speed was tested using timed letter comparison tasks during functional magnetic resonance imaging (fMRI).
The researchers found significant differences in brain activation between the SCI group and the age-matched control group; however, the SCI and older groups had similar patterns, including activation of the hippocampal, frontal, and parietal areas.
“This suggests that individuals with SCI are compensating for deficits in processing speed by relying on the areas of the brain involved in executive control and memory, which supports the theory of accelerated brain aging after SCI,” said researcher Nancy Chiaravalloti, PhD, in a press release.
There are various theories as to why cognitive decline might be accelerated after SCI. Spinal injury can damage the pathways that control the cardiovascular system, thereby altering blood flow in the brain. SCI is also associated with sleep apnoea and sleep loss, which may contribute to cognive decline. It should however be noted that many cases of SCI are caused by accidents that may also damage to the brain, which may be the cause of cognitive deficits in some cases. Likewise, the psychological trauma and stress following a violent accident could contribute to cognitive ageing.
It seems that more research will be needed to iron out exactly what links SCI to cognitive deficits. Understanding the risk factors behind these deficits should make us better equipped to prevent them.
Cognitive function after spinal cord injury: doi: 10.1212/WNL.0000000000006244