Birdwatching may show structural differences in the brain.

A Canadian study in the Journal of Neuroscience compared 29 expert and 29 novice birdwatchers and found lower mean diffusivity in certain brain regions of experts, a measure the researchers associate with greater tissue density and attention-related processing.

Researchers report that experienced birdwatchers showed measurable differences in brain scans compared with people who were not birding experts. The Canadian study, published in the Journal of Neuroscience, compared 58 adults split evenly into expert and novice groups. Experts were recruited from birding organizations and novices came from birding and other outdoor groups. The team used diffusion-weighted MRI and functional MRI to examine brain structure and activity. Key findings: - The study included 58 participants: 29 experts (ages 24–75) and 29 novices (ages 22–79), recruited from birding and outdoor organizations. - Diffusion-weighted MRI results showed lower mean diffusivity (MD) in certain brain regions of experts; lower MD is reported as associated with greater tissue density. - Lower MD in experts was linked with higher bird identification accuracy and described as a possible attenuation of age-related decline in those regions. - Functional MRI showed that a brain area with lower MD in experts was active when experts judged less-familiar, nonlocal bird species compared with local ones. - The lead author and outside experts emphasized that the study does not prove a causal effect and called for further research comparing different domains of expertise and examining lifestyle factors. Summary: These results align with prior work that links prolonged, domain-specific learning to differences in brain structure and activity, particularly in regions supporting attention and visual recognition. The researchers and independent commentators note the findings are informative but not proof of causation and recommend additional studies to compare types of expertise and the role of lifestyle influences.