Exercise (2015-17) Brain Volume & Functioning
Learn more about Alzheimer's disease and cognitive impairment.
In this study researchers narrowed their focus on exercise and brain functioning to evaluate the effect of exercise on blood flow to the brain in a subset of stroke patients. Cerebrovascular disease is a narrowing of the arteries leading to the brain. It causes or contributes to conditions such as strokes which can severely damage physical functioning and cognitive capacity, decision making and cause depression.
The researchers investigated the impact of moderately-intensive exercise on about 20 stroke patients with mild "subcortical ischaemic VCI." This means that these stroke patients had an obstruction which blocked blood flow to the brain. The patients received either three times a week moderate aerobic training for six months, or the care such patients would usually receive.
At the end of the study the patients taking aerobic training had improved flanker reaction time (a test involving cognition and reaction time) and had decreased lesions in the brain white matter.
The scientists reported that such aerobic exercise was beneficial for stroke patients and that larger-scale studies should be performed to validate their investigation.
Researchers: C.L. Hsu, J.R. Best, et al
Published: Aerobic exercise promotes executive functions and impacts functional neural activity among older adults with vascular cognitive impairment, British Journal of Sports Medicine, April, 2017.
Researchers investigated whether exercise could help patients who have only mild cognitive problems. Patients who have mild cognitive impairment (MCI) are at risk for developing Alzheimer's disease.
They used an MRI technique to look at the brain scans of patients who began a program of exercise four times a week and compared the results to patients who did stretching exercises only. Both groups exercised or stretched four times a week for a six month period.
One group of 16 adults averaging 63 years old performed aeorbic exercise such as walking on a treadmill, using a stationary bike, or a elliptical training machine. The other group of 19 patients with an average of 67 years old performed stretching exercises.
The scientists took MRI images of all of the participants at the beginning of the study period and after six months. They found that in both groups brain volume increased, including in the part of the brain responsible for short-term memory. The aerobic group had the greatest total brain volume protection, with increased stretching of connective tissue in the brain. The patients who only performed stretching experienced some atrophy in the connective fibers in the brain - which is held to be an indicator of loss of brain volume.
In addition, the participants who engaged in aerobic exercise were found to have markedly greater improvement in the capacity to plan, make decisions, discriminate.
Researchers: S. Craft, Y. Jung, et al,
Published: Aerobic Exercise Preserves Brain Volume and Improves Cognitive Function, Radiological Society of North America, November, 2016.
In an earlier study researchers investigated the relationship between cognitive capacity and the size of the brain. In many cognitive disabling conditions it has been observed that the physical size of the brain shrinks.
Researchers devised research to examine this relationship. They selected 110 people who were over 65 and who were healthy. Most of them were enrolled into an exercise group and they used home-based exercise regimens as well.
The study lasted for 2 years, and for an additional 6 months the researchers monitored the subjects after they had stopped the exercise programs.
The researchers used techniques such as MRI to produce images of the participants' brains during the course of the study. They found that while brain volume normally decreases with age, in these subjects prefrontal (both sides) volume was preserved but the benefit faded after the participants ceased the exercise program. The prefrontal part of the brain, the front of the brain, is needed for planning, cognitive behavior, decision making, and how the personality expresses itself. This is the part of the brain whose failure is most immediately noticeable in patients with cognitive impairment.
The scientists also monitored the participants' cognitive functioning in areas such as attentional shift. Attentional shift simply means the ability to shift the vision and thus attention from one point to another and to maintain that attention. Normally as we age it is increasingly difficult to maintain attention to one point. These patients saw improvement in this regard. This improvement persisted during the 6 months following the 2 year exercise period.
Researchers: M. Tamura, K. Nemoto, et al
Published: Long-term mild-intensity exercise regimen preserves prefrontal cortical volume against aging, International Journal of Geriatric Psychiatry, July, 2015.