As an athlete, I’ve never thought about how working out may affect my brain and cognitive abilities. My focus is always on the physical benefits of working out… losing weight, toning muscles, gaining strength etc. But now I am retired from varsity athletics and it’s safe to say the vigour of my workouts has declined. So how/ will this affect my brain as I age? A study titled Effects of Exercise Modes on Neural Processing of Working Memory in Late Middle-Aged Adults: An fMRI study (Chen, Chen, Schneider, Kao, Huang & Chang, 2019) was able to give me some insight into how different workout modes affect the adult brain.
To understand this study, it is important to note that a workout mode refers to the type of exercise an individual partakes in. The relationship between the mode of exercise and cognitive function underlying behavioral modification and neural activation has remained unknown and this is what Chen et al., sought to examine. Specifically, they examine the associations between different exercise modes and the working memory aspect of executive functioning, which essentially monitors and controls behavior.
To examine this, a sample of seventy middle-aged adults were classified into three groups based on their participation in exercise prior to the study. The first group was classified as the open skill group. The exercises they participated in were considered open skills such as basketball, table tennis, tennis and badminton. Group two was the closed skill group, taking part in activities such as jogging, cycling and swimming. The third group were made up of the remaining adults who took part in irregular exercises or low-intensity exercises within the past 3 months. The adults were assessed by a self-report questionnaire that asked how long they have been participating in their exercise mode, how often per week and the duration of each session. They also filled out the International Physical Activity Questionnaire (IPAQ) to indicate their amount of physical activity in the last week. To assess physical fitness of the participants, a general fitness test was administered to test both health and skill related fitness. Cardiovascular strength, muscular strength, muscular endurance and flexibility, agility and power were assessed.
The working memory fMRI task involved a computerized spatial working memory task with three working memory conditions (1 dot, 3 dots, and 7 dots). Combinations of the three conditions were presented in two experiments. The participant was required to react to the presentation of a white coloured stimulus by pressing the left or right button on a keyboard to indicate if the display showed a dot in a matching condition as the previous. After these displays, trials were randomly separated by intervals of 10.5, 13.5 or 15.5 seconds, with a blank background. The reaction time and accuracy were recorded as the measure of working memory performance.
The blood oxygenated level-dependent (BOLD) response during the first phase of the experiment. The spatial working memory paradigm included a fixation with white colour on the black screen, followed by an encoding display (500 milliseconds) with one of the three working memory load conditions. After 3000 milliseconds, a fixation with white colour was presented on a gray screen, followed by a single dot presentation with a single dot that appeared on either a previously shown location or not. Accuracy on the location of the dot was measured. During this task, the participant was under-going an fMRI
Results of the fMRI scan showed both exercise groups showed better spatial working memory and physical fitness performance compared to the control group. The open-skill group showed significantly greater neural activation in the prefrontal lobe, anterior cingulate cortex/supplementary area, and hippocampus than the closed skill group. Additionally, the open skill group demonstrated significantly increased brain activation during the 3-dot and 7-dot conditions, where the closed skill group demonstrated the most during the 1-dot condition.
These results suggest that exercise not only improves physical health, but also cognitive health. It also improves working memory, enhances neuro-cognitive scaffolding in middle-aged adults and indicates that different exercise modes can successfully modulate frontal and hippocampal function when facing age-related neurocognitive declines.
Chen, F.-Z., Chen, Y.-P., Schneider , S., Kao, S.-C., Huang, C.-M., & Chang, Y.-K. (2019). Effects of Exercise Modes on Neural Processing of Working Memory in Late Middle-Aged Adults: An fMRI study. Frontiers in Aging Neuroscience , 11(24), 1–12. doi: 10.3389/fnagi.2019.00224
