Nearly half of all dementia cases could be prevented through lifestyle changes, with factors such as exercise, diet, and social connection playing an important role in shaping an individual’s risk. But what if these risk factors were also leaving subtle chemical traces in the brain—well before any symptoms of dementia appeared?
A research team at the University of the Sunshine Coast’s Thompson Institute believes they have uncovered exactly that. Their findings open up new avenues for early detection in dementia research and deepen our understanding of the biological processes that increase vulnerability to cognitive decline.
The study, published today in Cerebral Cortex, used Magnetic Resonance Imaging and MR-spectroscopy to examine the brain chemistry of 79 healthy older adults. All participants had normal memory, thinking abilities, and cognitive function, but their “modifiable dementia risk scores” differed, based on health and lifestyle factors such as physical activity, diet, sleep quality, and social engagement.
Lead author Dr Jacob Levenstein explained that the team identified distinct patterns in brain chemistry linked to higher dementia risk. In particular, they focused on Gamma-aminobutyric acid (GABA), a key neurochemical often described as the brain’s “brake system” because it calms neural activity and maintains balance in brain networks. Individuals with higher risk scores were found to have lower GABA concentrations in sensory and motor regions of the brain.
The researchers also found that in the prefrontal cortex—the brain’s “command centre” for decision-making and complex thought—higher risk scores were associated with lower levels of two additional neurochemicals: total N-acetylaspartate (tNAA) and total choline (tCho). Both play vital roles in sustaining brain tissue and supporting cell-to-cell communication. According to Dr Levenstein, diminished levels of these markers suggest that subtle brain deterioration may begin long before behavioural or memory changes become evident.
These findings are significant because they identify three potential neurochemical warning signs of dementia in otherwise healthy adults. As Dr Levenstein noted, this opens the possibility of detecting dementia risk years before symptoms appear, creating opportunities for earlier intervention and prevention strategies.
Co-author Dr Sophie Andrews, Lead of the Thompson Institute’s Healthy Brain Ageing Program, emphasised that the encouraging aspect of this research is its focus on modifiable factors. “Simple lifestyle adjustments can change the trajectory of brain health,” she said. “Improving sleep quality, increasing physical activity, looking after mental health, and adopting a Mediterranean-style diet are all proven ways to strengthen long-term brain function.”
More information: Jacob Levenstein et al, Neurophysiological correlates of modifiable dementia risk factors in cognitively unimpaired older adults, Cerebral Cortex. DOI: 10.1093/cercor/bhaf179
Journal information: Cerebral Cortex Provided by University of the Sunshine Coast
