Brain Health Blog

Elizabeth Buchen, neuroscientist, science writer and advisor to Lumos Labs, continues her discussion of cognitive reserve with a specific example.

The cognitive reserve hypothesis has recently been supported by findings of Dr. Margit Bleecker, who studied the effects of lead exposure on cognitive function. The study involved 112 lead smelter workers in New Brunswick, who were divided into groups with high reading ability (12th grade or higher) and low reading ability (11th grade or lower). Reading ability is a recognized measure of cognitive reserve, and is perhaps a better metric than education and occupation (e.g. it distinguishes self-taught individuals who dropped out of school for economic reasons from people who graduated high school but are functionally illiterate). Importantly, although lead exposure has negative effects on many brain functions, well-ingrained functions like reading ability are resistant to the consequences.

Both groups had similar lead exposure, age, alcohol use, and depression levels, but those with high cognitive reserve performed 2.5 times better on cognitive tests than those with low cognitive reserve. In contrast, cognitive reserve did not protect motor speed and dexterity from the toxic effects of lead, indicating that other parts of the workers’ nervous systems were still vulnerable. These findings, published in Neurology, demonstrate that cognitive reserve protects against the cognitive effects of chronic lead exposure.

The key to cognitive reserve is not to wait until you’re in your 60s (or even 50s, 40s, 30s, or 20s, for that matter), but to challenge yourself intellectually as early and often as possible. Further, a comprehensive “neuroprotective lifestyle” involves not only brain activities, but also physical activity and a healthy diet.