Association between brain structure and fine motor function: findings from the population-based Rhineland Study.

Area of Science:

• Neuroscience
• Human Anatomy
• Gerontology

Background:

• Previous studies show inconsistent associations between brain atrophy and fine motor function.
• Investigated the link between fine motor skills and age/sex-related brain structure changes in a large cohort.

Purpose of the Study:

• To determine if decreased fine motor function correlates with age- and sex-associated brain structure changes.
• To explore the relationship between specific fine motor skills and brain morphology across the adult lifespan.

Main Methods:

• Utilized cross-sectional data from 8318 participants (aged 30-95) in the population-based Rhineland Study.
• Assessed fine motor skills using a digital spiral drawing test (tracing precision, velocity, tremor frequency).
• Analyzed brain volumetric and cortical thickness measures from 3T T1 MRI scans, with multivariable regression adjusting for covariates.

Main Results:

• Smaller total brain volume and thinner precentral gyrus cortex were linked to decreased tracing precision and increased tremor.
• Reduced hippocampal volume correlated with decreased tracing precision.
• Lower tracing velocity was associated with smaller total cerebellar and cerebellar grey matter volumes.
• Women exhibited better fine motor function, but age-associated changes did not differ by sex.

Conclusions:

• Fine motor function is impaired in older adults and superior in women.
• Brain structure, including total brain volume and motor cortex thickness, is significantly associated with fine motor function, particularly tracing precision.