Semantic memory functional MRI and cognitive function after exercise intervention in mild cognitive impairment. J Alzheimers Dis 2013;37(1):197-215
Date
06/28/2013Pubmed ID
23803298Pubmed Central ID
PMC4643948DOI
10.3233/JAD-130467Scopus ID
2-s2.0-84883172201 (requires institutional sign-in at Scopus site) 114 CitationsAbstract
Mild cognitive impairment (MCI) is associated with early memory loss, Alzheimer's disease (AD) neuropathology, inefficient or ineffective neural processing, and increased risk for AD. Unfortunately, treatments aimed at improving clinical symptoms or markers of brain function generally have been of limited value. Physical exercise is often recommended for people diagnosed with MCI, primarily because of its widely reported cognitive benefits in healthy older adults. However, it is unknown if exercise actually benefits brain function during memory retrieval in MCI. Here, we examined the effects of exercise training on semantic memory activation during functional magnetic resonance imaging (fMRI). Seventeen MCI participants and 18 cognitively intact controls, similar in sex, age, education, genetic risk, and medication use, volunteered for a 12-week exercise intervention consisting of supervised treadmill walking at a moderate intensity. Both MCI and control participants significantly increased their cardiorespiratory fitness by approximately 10% on a treadmill exercise test. Before and after the exercise intervention, participants completed an fMRI famous name discrimination task and a neuropsychological battery, Performance on Trial 1 of a list-learning task significantly improved in the MCI participants. Eleven brain regions activated during the semantic memory task showed a significant decrease in activation intensity following the intervention that was similar between groups (p-values ranged 0.048 to 0.0001). These findings suggest exercise may improve neural efficiency during semantic memory retrieval in MCI and cognitively intact older adults, and may lead to improvement in cognitive function. Clinical trials are needed to determine if exercise is effective to delay conversion to AD.
Author List
Smith JC, Nielson KA, Antuono P, Lyons JA, Hanson RJ, Butts AM, Hantke NC, Verber MDAuthors
Piero G. Antuono MD Professor in the Neurology department at Medical College of WisconsinAlissa Butts PhD Associate Professor in the Neurology department at Medical College of Wisconsin
Kristy Nielson PhD Professor in the Psychology department at Marquette University
MESH terms used to index this publication - Major topics in bold
AgedAged, 80 and over
Cognition
Cognitive Dysfunction
Exercise
Female
Humans
Magnetic Resonance Imaging
Male
Memory
Memory Disorders
Middle Aged
Psychomotor Performance