The Resilient Brain: How Our Brains Adapt and Compensate

By Kamen Tsvetanov , Alzheimer’s Society Research Leader Fellow at the 英国剑桥大学 .

We all know that as we get older, our brains change. Connections between brain regions get lost, processing slows down, and those pesky "tip of the tongue" moments become more frequent. For those among us facing Alzheimer's or other age-related cognitive decline, these changes can feel frightening or discouraging.

According to our new research from the University of Cambridge and University of Sussex, as some areas deteriorate with age, other regions can compensate by taking on new roles in thinking and memory. While it is widely acknowledged that aspects of fluid intelligence – things like reasoning ability and problem solving – tend to decline as we get older, intriguingly, some seniors demonstrate resilience that enables them to maintain this ability better than others.

In this study, our team of researchers used brain imaging to monitor activity while participants worked on a puzzle task. We found that while older people solved the problems new areas like the cuneus, at the rear of the brain, and frontal cortex lit up beyond the main ‘thinking regions’.

The novel part of the study was that the activity of the cuneus in older adults was directly linked to better performance and contained extra information about the task beyond the ‘thinking regions’! So your brain isn't just adapting randomly - it seems to actively call up resources exactly when and where they're needed.

This leads us to believe that similar compensatory adaptation could happen in preclinical dementia stages as well, allowing us to explain why certain high-risk individuals maintain normal cognition longer than others.

The exciting part of the study was that this compensation depends on the individual - some seniors show much more ability to activate these helper areas. That suggests there are likely factors, like lifestyle, environment, and genetics, that affect cognitive resilience. Understanding what these influencing factors are, can open new ways for protecting, and even boosting our brains' compensation ability.

Going forward, we aim to directly study cognitively intact people with high risk of dementia to track when and how their brains recruit extra support before they show dementia symptoms. Determining the influencing factors and how at-risk brains compensate could help us develop strategies to boost this process early on, delay symptoms onset and prolong cognitive health even in the face of accumulating damage.

The research was supported by the Medical Research Council, the Biotechnology and Biological Sciences Research Council, the European Union’s Horizon 2020 research and innovation programme, and Fellowship awards from Guarantors of Brain and Alzheimer’s Society.

Keen to read more – Kamen’s research is published here:

Knights, E. et al. Neural Evidence of Functional Compensation for Fluid Intelligence Decline in Healthy Ageing. eLife; 6 Feb 2024; DOI: 10.7554/eLife.93327