Birdwatching May Help Protect the Brain Against Cognitive Decline

Research indicates that learning languages and making art can help keep the brain sharp in later life. Birdwatching, it appears, may offer comparable benefits.

Birdwatching and brain structure

A new Canadian study has found that experienced birdwatchers had denser, more intricate tissue structures in brain areas associated with attention and perception than beginners did.

The results add weight to the concept of neuroplasticity: using the brain in particular ways may reshape its wiring to a degree, potentially helping to guard against cognitive decline in later life.

"Regions involved in attention and perception showed structural modification in experts, and these same regions were selectively engaged to support identification in challenging circumstances," the researchers write in their published paper.

"Results also suggest that knowledge acquisition might mitigate age-related decline in circumscribed brain regions supporting expert performance."

The researchers assessed brain structure and processing simultaneously. They carried out MRI scans on 29 expert birdwatchers and 29 novice birdwatchers who were matched by age and education. While inside the MRI scanner, participants had to identify pictures of different birds. The scans were subsequently assessed using a measure of brain complexity known as "mean diffusivity."

"The measure we used is the diffusion of water molecules in the brain," says neuroscientist Erik Wing, at the Rotman Research Institute in Canada. "One way of putting it is that there's less constraint on where water goes in the brains of experts."

How expertise may support cognition

As expected, seasoned birdwatchers showed lower mean diffusivity in brain regions involved in recognising birds, suggesting these areas may have received something akin to a system upgrade. Furthermore, when they viewed birds they did not know, those same regions became active.

There were also more modest indications of possible protection from cognitive decline later in life. Brain tissue normally becomes less complex with age, reflected in higher mean diffusivity, but this process seemed to be advancing more slowly than usual among the expert birdwatchers.

"Acquiring skills from birding could be beneficial for cognition as people age," says Wing.

Birdwatchers make an appropriate group for this kind of research because their pastime combines identifying important details within abundant visual information with sustaining attention for long stretches. After all, a rare bird could appear at any moment.

Limits of the birdwatching study

Although the observed brain differences are encouraging, the findings should not be interpreted too widely. The volunteers did not undergo tests of memory or cognition, for instance, so the firm conclusion is only that experts’ brains appeared especially tuned to their own area of expertise.

Establishing cause and effect is also challenging in a single study that did not follow participants over time. The experts may have already possessed particular beneficial brain characteristics that initially drew them towards birdwatching.

Still, the more likely explanation is that years spent on the hobby shaped birdwatchers’ brains in this manner. The researchers propose that future research could examine whether such optimisations can also assist with cognitive tasks beyond birdwatching.

Related research has shown that learning an instrument or a new language can alter brain structures and may postpone some natural age-related decline. This latest study indicates that birdwatching might likewise train related brain regions and potentially offer protection against cognitive decline.

"Given findings that older experts can harness specialized knowledge to support cognition involving their domain of experience, future work will be needed to uncover how age-related structural trajectories affect specialized performance later in life," write the researchers.

The research was published in The Journal of Neuroscience.