Get Smart: Fitness Improves Spatial Memory

Do brilliant scientists such as Albert Einstein have a bigger brain than the average human being? Conversely, do students who perform poorly on intelligence tests have a smaller brain than those with remarkably high scores? Neuroscientists suggest that individuals with bigger brains are not necessarily smarter, but several studies have indicated the size of the hippocampus (the part of the brain responsible for memory formation) as a robust predictor of memory performance. In other words, having a bigger hippocampus (pictured below) is indeed better. Previous experiments have identified memorizing geographical information and studying for finals as examples of activities that increase hippocampus size, but these findings have limited applications to the real world. Although memory loss and other natural aging processes are largely unavoidable, evidence from recent developments in health care research signify physical exercise’s crucial role in enlarging the hippocampus and thereby counteracting cognitive decline that is detrimental to elderly individuals' independent lifestyles.

The scientific community has generated several ideas about how to enhance memory formation, but many of these suggestions lack practicality and applicability. For example, a study found that London taxi drivers have bigger hippocampi than control subjects because their profession involves memorizing the locations of major streets in London. Despite this confirmation of the hippocampus’ role in spatial memory, or the storage of information regarding the location of physical objects in space, most individuals do not have the time or motivation to memorize maps of London or other major cities solely for the purpose of improving spatial memory or enlarging their hippocampi. This gap between scientific research and reality was also manifested in findings that German medical students' hippocampi increased in size as they studied for final exams. Gray matter in the posterior hippocampus increased consistently during and even three months after the learning period. Since I was unable to retrieve the original publication of this study, I could not ascertain the primary factor underlying this change in the hippocampus. However, I did come up with several possible explanations for this phenomenon. Perhaps hippocampal size increases when extra mental effort is required for a task such as studying. Alternately, hippocampal size increase may be dependent on the type of information studied (medicine in this case). Even though the investigation provided evidence for the benefits of testing procedures (finals) in the education system, it is irrelevant to individuals who are no longer in school, most notably the elderly population. Like the taxi driver study, it did not offer any viable solutions for resisting age-related memory decline in the elderly population.

Undoubtedly, there is a large proportion of seniors who live independently despite the inconvenience caused by reduced memory capacities and other cognitive problems. So why should researchers help this population maintain mental competency by proposing new ways to improve memory? According to a researcher who published a paper in the most current issue of the journal Hippocampus, impairment of spatial memory "is one of a number of reasons why older people end up losing their independence." Furthermore, statistics from the American Psychiatric Association show that fifteen to twenty-five percent of elderly people in the United States suffer from significant symptoms of mental illness. If this pattern persists, our health care system must prepare to provide support for at least 18 million of the 72 million American baby boomers who are expected to turn 65 over the next two decades. Since our health care system is already struggling with the number of elderly patients with cognitive degeneration, it is imperative for researchers and physicians to educate the aging population about ways to protect themselves. America's health care system cannot cope with a dramatic increase in the number of elderly patients who require long-term, full time care as a result of severe or even moderate mental decline.

Until recently, most people believed that the intrinsic properties of our brains remain unalterable after birth; we can accumulate knowledge, but we cannot improve our intelligence or our performance on IQ tests no matter how hard we try. Contrary to conventional wisdom, new evidence suggests that physical exercise can alter specific brain region, thus leading to radical improvements in cognitive function. For example, a 2006 study in the Journal of Aging and Physical Activity found that strength training (pictured above) increased participants' working memory span. The higher the level of resistance, the bigger the improvement in short-term memory. At McGill University in Montreal, scholars concluded that participants, ages 62 to 90, who danced two hours twice a week for 10 weeks improved in balance, posture and motor coordination, as well as cognition. Recent experimental data proposed exercise as the most effective way to increase hippocampus size and subsequently improve spatial memory. Researchers discovered that elderly individuals who are physically fit retain key regions of their brain involved in learning and memory. Even though natural aging processes are largely unavoidable, physical exercise is the best way to counteract physical and cognitive decline due to brain volume shrinkage (which begins at a rate of 1% every year after age 65). It also has many physical health benefits as discussed in my previous posts. Crucially, this activity could be accomplished without expensive equipment and could be done virtually anywhere at anytime.

Individuals with impaired cognitive abilities simply cannot live independently and consequently rely on health care professionals for their daily needs. According to the American Geriatrics Society, "mental illnesses, including depression, paranoia, and dementias, such as Alzheimer's disease, are clearly among the most physically, emotionally, and economically devastating illnesses that commonly affect elderly persons. By some accounts, over $15 billion a year are spent on the care of victims of dementias alone." Even though President Obama promises to lower health care costs and make health insurance affordable and accessible to all, his plan does not involve increasing the number of health care providers. As mentioned above, the United States government would have to provide for 18 million baby boomers with significant symptoms of mental illness (within the next two decades) if the current trend continues. Logically, the only way to cater to the increased needs of dependent patients is to sacrifice quality of health care available to each patient. In closing, I strongly urge the government and physicians to promote consistent participation in physical activities because exercise effectively prevents or delays the onset of multiple age-related physical and mental disorders.