Inter-individual Differences in Exercise-Induced Spatial Working Memory Improvement: A Near-Infrared Spectroscopy Study

Yudai Yamazaki; Daisuke Sato; Koya Yamashiro; Atsuhiro Tsubaki; Yui Yamaguchi; Nana Takehara; Atsuo Maruyama

doi:10.1007/978-3-319-55231-6_12

Inter-individual Differences in Exercise-Induced Spatial Working Memory Improvement: A Near-Infrared Spectroscopy Study

Adv Exp Med Biol. 2017:977:81-88. doi: 10.1007/978-3-319-55231-6_12.

Authors

Yudai Yamazaki¹, Daisuke Sato², Koya Yamashiro², Atsuhiro Tsubaki², Yui Yamaguchi³, Nana Takehara², Atsuo Maruyama²

Affiliations

¹ Institute for Human Movement and Medical Sciences, Niigata University of Health and Welfare, Niigata, Japan. wtm15009@nuhw.ac.jp.
² Institute for Human Movement and Medical Sciences, Niigata University of Health and Welfare, Niigata, Japan.
³ Analytical and Measuring Instruments Division, Shimadzu Corporation, Kyoto, Japan.

PMID: 28685431
DOI: 10.1007/978-3-319-55231-6_12

Abstract

Acute aerobic exercise at a mild intensity improves cognitive function. However, the response to exercise exhibits inter-individual differences, and the mechanisms underlying these differences remain unclear. The objective of this study was to determine potential factors in the brain that underlie differential responses to exercise in terms of cognitive improvement using functional near-infrared spectroscopy. Fourteen healthy subjects participated in these experiments. Participants performed a low intensity cycling exercise at 30% maximal oxygen uptake (VO_2peak) for 10 min and performed a spatial memory task before and after exercising (5 and 30 min). The spatial memory task comprised two levels of difficulty (low: 1-dot EXERCISE, high: 3-dot EXERCISE). Cortical oxy-hemoglobin (O₂Hb) levels were recorded using near-infrared spectroscopy during both the exercise and the spatial memory task phases. Regions of interests included the dorsolateral prefrontal cortex (DLPFC), ventrolateral prefrontal cortex (VLPFC), and frontopolar area (FPA). The participants were divided into two groups depending on whether they were responders (improved task reaction time) or non-responders (no improvement). Subsequently, we analyzed the group characteristics and differences in the change in O₂Hb levels during exercise and spatial working memory tasks. Acute mild exercise significantly improved mean reaction times in the 1-dot memory task but not in the 3-dot task across the participants. In the 1-dot EXERCISE, 10 subjects were responders and four subjects were non-responders, whereas in the 3-dot EXERCISE, seven subjects were non-responders. In responders, during exercise, we found higher O₂Hb levels in the right VLPFC response for the 1-dot memory task. Acute mild exercise caused inter-individual differences in spatial memory improvement, which were associated with changes in O₂Hb activity in the prefrontal area during the exercise phase but not during the actual spatial memory task. Therefore, individuals who respond with higher reactivity to mild intensity exercise in the VLPFC might obtain larger spatial working memory improvements following exercise than non-responders.

Keywords: Aerobic exercise; Functional near-infrared spectroscopy; Inter-individual difference; Low intensity; Spatial working memory.

MeSH terms

Adult
Brain Mapping / methods*
Cognition / physiology
Exercise / physiology*
Exercise / psychology
Female
Humans
Individuality*
Male
Memory, Short-Term / physiology*
Reaction Time
Spatial Memory / physiology*
Spectroscopy, Near-Infrared*
Young Adult