U.S. — Researchers led by Princeton University neuroscientist Frederick d'Oleire Uquillas reported findings on June 10 in the journal Nature Neuroscience. The study indicated that larger cerebellums, particularly in rear regions resistant to age-related shrinkage, were linked to better cognitive function in older adults and those in the early stages of Alzheimer's disease.

The study team analyzed brain scans and cognitive test scores from more than 700 U.S. adults for their initial analysis. This data was collected as part of the Human Connectome Project. Cognitive tests measured abilities, including short-term memory, attention, language, and the ability to visualize 3-D objects. Data from the research showed that the cerebellum tended to become smaller with increasing age. However, larger cerebellums, especially in posterior regions, correlated with higher scores on these cognitive tests. This correlation between cerebellum size and cognitive scores remained consistent even after accounting for different education levels among the participants.

Researchers also found the same link between cerebellum size and cognition in over 35,000 adults from the U.K. Biobank. Scans of larger cerebellums revealed more brain tissue and increased connections between nerve cells. The team additionally analyzed data from approximately 1,350 U.S. and Canadian adults participating in the Alzheimer's Disease Neuroimaging Initiative. Among these 1,350 adults, 644 had accumulated a high level of amyloid plaques.

At the early stages of Alzheimer's disease, prior to amyloid plaque accumulation, a larger cerebellum correlated with a higher cognitive score. The research team stated they could not determine whether a larger cerebellar size directly caused improved cognition in older age. "It's not all doom and gloom," d'Oleire Uquillas said. "There's hope there."

Vonetta Dotson, a neuropsychologist at Brigham and Women's Hospital in Boston, was not involved with the study. "The more we understand its role in both normal aging and disease, the more we can understand whether or not it should be a target for treatment in medical conditions," Dotson said. Dotson is also the founder of a company that offers assessments, counseling, and interventions to promote aging brain health. The majority of the study data came from white individuals with high levels of education.