Your Mind's Stockpile Against MS

Cognitive impairment in multiple sclerosis reduced by brain reserve and cognitive reserve

(RxWiki News) Multiple sclerosis (MS) can seriously affect a person's ability to learn and remember information. But spending the time for leisurely learning early in life may help protect against this mental decline.

A team of researchers recently tested two theories related to mental function in patients with MS. The first theory is known as the "brain reserve" hypothesis and the second is called "cognitive reserve" hypothesis.

The brain reserve hypothesis suggests that patients with bigger brains have more brain to lose before they start to feel the damaging effects of MS on the mind. 

The idea of cognitive reserve suggests that doing things that make us smarter — such as having a good education or engaging in leisurely learning — can protect against cognitive decline, or a decline in memory and thinking skills.

The researchers found that brain reserve, or having a bigger brain, protected against MS-related thinking problems but not memory problems. Cognitive reserve, on the other hand, protected more against memory problems than thinking problems.

These findings suggest that making lifestyle choices to enrich the mind could help MS patients avoid mental problems.

"Take the time to exercise your mind."

This study was led by James F. Sumowski, PhD, of the Kessler Foundation Research Center in West Orange, New Jersey.

The aim of this study was to see if brain reserve protected against cognitive impairment (problems with memory and thinking) in patients with MS. The researchers also wanted to see if cognitive reserve could protect against that same problem independently of brain reserve.

The study involved 62 patients with MS — 41 with relapsing-remitting MS and 21 with secondary progressive MS.

Relapsing-remitting MS is characterized by periods in which symptoms flare-up (relapse) followed by periods of recovery (remission). Secondary progressive MS, which often happens in patients with relapsing-remitting MS, is characterized by periods of relapse and partial remission, but the symptoms don't fully disappear between periods.

For this study, participants' brain reserve was measured as their maximal lifetime brain volume, or the size of their brains. Cognitive reserve was measured as early-life cognitive leisure (the time spent on intellectually enriching activities in early life).

While brain volume is determined by genetics, cognitive reserve may be a modifiable factor. Put simply, people can't change their brain volume, but they can choose to do more leisurely learning.

The researchers measured cognitive status by having the study participants do a variety of tasks that demonstrated their thinking and memory abilities.

Disease burden, or how far MS had progressed, was measured with brain scans that can show damage and shrinking of brain tissue.

Study results showed that a larger brain volume, or brain reserve, reduced the negative effects of MS on cognitive status, or more specifically on thinking skills. According to the researchers, this finding supports the brain reserve hypothesis in MS.

This study also showed that early-life intellectual enrichment, or cognitive reserve, protected patients from cognitive problems.

What's important to note is that cognitive reserve protected patients regardless of their brain reserve.

Dr. Sumowski and colleagues concluded that their study supports the brain reserve hypothesis and that cognitive reserve independently protects against cognitive decline in MS even more than brain reserve.

"Lifestyle choices protect against cognitive impairment independently of genetic factors outside of one's control," they wrote.

This study was published June 11 in Neurology.

The research was funded in part by the National Institutes of Health.

Dr. Sumowski reported no potential conflicts of interest. However, some of the co-authors reported ties to a variety of pharmaceutical companies and governmental institutions.

Review Date: 
July 1, 2013