Extensive Prefrontal Cortex Haemodynamic Changes Provoked By Intense Aerobic Exercise, Measured Via FNIRS

Abstract

Physical exertion is sometimes associated with changes in cognitive function. However, there is a dearth of literature on the physiological basis of these associations. PURPOSE: To determine the acute effects of intense physical exercise on executive function and prefrontal cortex brain activity, and the impact of baseline fitness on these associations. METHODS: 103 participants (F = 29, M= 74; Age = 40 ± 8) completed tests of executive function before and after undergoing a VO2max test with a Bruce Treadmill Protocol. A comparison control group of 32 participants matched for age, birth sex and fitness completed the same tests before and after active rest. Body fat % was determined via bioelectrical impedance and VO2max via gas analysis. The cognitive tests measured reaction time, control inhibition, stimulus-oriented & stimulus-independent thought, and source memory. Brain activity of the prefrontal cortex was measured during the pre-and post-exercise cognitive tests using functional Near Infrared Spectroscopy (fNIRS). RESULTS: The cohort's mean body fat was 25 ± 7 %, Anaerobic Threshold (AT) was 28 ± 5 ml/kg/min and VO2max was 38 ± 7 ml/kg/min.At baseline, there was no association between body fat % or VO2max and cognitive test performance. However, after exercise, participants showed significantly improved cognitive speed with no decrease in accuracy (F = 28.1; p<.001). The degree to which individual participants showed this exercise-related cognitive enhancement was reflected in changes in oxygen utilisation in the prefrontal cortex, in the regions associated with performances on the individual tasks, beyond those occurring in the no-exercise control group (n = 92, α < .05, FDR corrected). In addition, the exercise-related cognitive speed improvements were significantly negatively associated with body fat % (R 2 = 11.4%; p = .001) and with age (R 2 = 11.0%; p = .001) and were positively correlated with VO2/kg at AT (R 2 = 6.9%, p = .008) and VO2max (p = .003). CONCLUSION: Exercise improved prefrontal cortex brain activity and cognitive processing speed with no detriment to accuracy in executive function in healthy adults. Although all participants improved after exercise, those with a higher body fat percentage, lower cardiovascular fitness and older age showed proportionally less improvement.

Shedding Light on the Effects of Orienteering Exercise on Spatial Memory Performance in College Students of Different Genders: An fNIRS Study

“…The theory of cortical plasticity suggests that structural and functional improvements in different regions of the brain can be made by means of cognitive training. Aerobic exercise has been found to play a facilitative role in improving brain plasticity and cognitive function through neuroimaging monitoring [ 25 , 26 ], and aerobic exercise enhances spatial memory by improving brain activity and cognitive processing speed in the prefrontal cortex [ 27 , 28 ]. Aerobic exercise can also affect the activation patterns of the brain regions that are involved in higher cognitive functions and their functional connectivity, in addition to its effects on the structure of movement-related brain regions [ 29 , 30 , 31 ].…”