Schizophrenia Daily News Blog

Reading Ability Can Protect Brain From Lead Exposure, Brain Disorders

Research studies have shown how children exposed to enriched learning environments when they are young, have lower risk of schizophrenia and other brain disorders later in life. This "cognitive reserve" has also been identified in brain neuroplasticity research that has demonstrated that well-exercised brains grow stronger, just as muscles do. It turns out that brain fitness is as important as physical fitness in long term health, and its best if you start young (and its good to start children reading young). The more you exercise your brain, the more resilient it seems to get to stresses and even toxins.
Researchers we've talked to have suggested that encouraging and teaching your children to read and learn throughout their lives is something that should be highly encouraged for everyone for general brain health.

A new study that further demonstrates this was published in the July issue of Neurology, the medical journal of the American Academy of Neurology that looked at cognitive reserve and the effects of toxins on the brain. They found that the effects of lead on cognition were less pronounced in those with more verbal skills. lead has in the past been shown to be a toxin that seems to increase risk for schizophrenia if exposed during pregnancy/early childhood.

The lead author of the study, Dr. Margrit L. Bleecker, said the findings supported the argument that reading level gives more insight into health than how much schooling a person has had. In this case, smelter workers who scored at an 11th-grade level or lower on a reading test had more than twice the level of cognitive effects from the lead.

"Lead smelter workers who are better readers have more protection against the effect of lead exposure on the brain than those who do not read as well"

The study was conducted on 112 smelter workers who were exposed to lead through their job. These workers were tested with cognition exams, motor speed tests, and reading ability. They analyzed these performance scores to their lifetime lead exposure (they had access to previous blood tests obtained through their employer as part of the protective monitoring that occurs in jobs with toxic exposure). Based on their performance, the workers were put into a group; a reading level of 12th grade or higher, and low cognitive reserve, a reading level of 11th grade or lower.

Previous studies have documented that this type of lead exposure – which is often long term and in large amounts – has negative impacts on nerves and brain regions. Ultimately, these affected brain regions will cause decreased function, or cognitive deficits.

Reading, however, seems to be one brain function that is resistant to the effects of lead exposure. Reading ability is said to be an indicator of cognitive reserve - the brain's resilience to neuropathological damage. Other factors contributing to cognitive reserve are overall verbal ability, education, and genetics.

“Even though the two groups had similar lead exposure, the cognitive effects of lead were 2.5 times greater in workers with low reading ability. In contrast, the effect of lead on motor speed was comparable in both groups as cognitive reserve does not apply to motor speed,” said study author Margit L. Bleecker, MD, PhD, with the Center for Occupational and Environmental Neurology in Baltimore, MD, and member of the American Academy of Neurology. “This suggests that high cognitive reserve has a protective effect that allowed these workers to maintain their functioning, even though lead affected their nervous system as shown by its effect on their motor skills.”

This reminds us of the longitudinal study conducted on nuns, often referred to as “The Nun Studies”. They found that verbal ability in the early 20’s of these nuns predicted whether or how severely they were affected by age related memory issues and even Alzheimer’s disease. Some nuns had no symptoms associated with Alzheimer’s, but following their death, autopsies revealed Alzheimer brains. Again, this shows that cognitive reserves, when reinforced, can provide great protection against brain disorders.

Related Reading:

Enriched Educational, Nutrition and Social Environments Lower Risk of Schizophrenia

The Brain That Changes Itself: Stories of Personal Triumph from the Frontiers of Brain Science

A “cognitive reserve” is a good thing to work on! (Michael Merzenich, Neuroscientist)

Read Full Article:

M. L. Bleecker, MD, PhD, D. P. Ford, MD, MPH, M. A. Celio, BA, C. G. Vaughan, MA and K. N. Lindgren, PhD. (2007). Impact of cognitive reserve on the relationship of lead exposure and neurobehavioral performance. NEUROLOGY;69:470-476.