Loss of Autobiographical Memory Due to Structural Brain Changes After Severe TBI
After experiencing a traumatic brain injury (TBI), patients often report memory loss among other common neurological deficits. Autobiographical memory, one’s lifelong collection of personal past events, is particularly vulnerable to damage, because a TBI often reduces brain volume in structural areas involved with memory processing. This relationship between TBI-induced volume loss and deficits in autobiographical memory is not well understood and remains an area of interest for memory researchers.
A recent Canadian study examined the interaction between injury severity and degree of autobiographical memory loss in 70 patients with TBI. Researchers assessed the participants’ autobiographical memory by administering the Autobiographical Interview test, which involves recall tasks designed to specifically target autobiographical memories. The participants then underwent MRI scans (which produce a structural image of the brain) to determine any brain lesions or volume loss as a result of their TBI. They found that:
- Only those participants with severe TBI demonstrated autobiographical memory deficits.
- Performance on autobiographical memory tasks was not significantly correlated with performance on other neurological assessments.
- Across all participants, poorer performance on autobiographical memory tasks was associated with lower brain volume in areas that process autobiographical memory.
These findings indicate that brain volume loss as a result of TBI is linked to autobiographical memory processing, and that people who have sustained a particularly severe TBI are at higher risk of memory deficits. While assessing MRI scans, clinicians should be aware that those with reduced brain volume may need targeted memory intervention during their post-injury treatment.
Esopenko C & Levine B. Autobiographical memory and structural brain changes in chronic phase TBI. Cortex. (January 2017).