TY - JOUR
T1 - Increased prefrontal oxygenation prior to and at the onset of over-ground locomotion in humans
AU - Matsukawa, Kanji
AU - Asahara, Ryota
AU - Ishii, Kei
AU - Kunishi, Mayo
AU - Yamashita, Yurino
AU - Hashiguchi, Yoshiki
AU - Liang, Nan
AU - Smith, Scott A.
N1 - Funding Information:
This study was supported by Grant-in-Aid for Scientific Research (B) (15H03061) and Grant-in-Aid for Exploratory Research (16K12935) from the Japan Society for the Promotion of Science and partially supported by the Center of Innovation Program from the Japan Science and Technology Agency.
Funding Information:
We thank Kenichi Shibachi (Zero C Seven Inc., Japan) for kindly lending us the PortaPress. This study was supported by Grant-in-Aid for Scientific Research (B) (15H03061) and Grant-in-Aid for Exploratory Research (16K12935) from the Japan Society for the Promotion of Science and partially supported by the Center of Innovation Program from the Japan Science and Technology Agency.
Publisher Copyright:
Copyright © 2020 the American Physiological Society
PY - 2020/11
Y1 - 2020/11
N2 - Our laboratory has reported with near-infrared spectroscopy (NIRS) that prefrontal oxygenated-hemoglobin concentration (Oxy-Hb), measured as index of regional cerebral blood flow, increased before and at the onset of arbitrary (i.e., noncued) ergometer exercise in a laboratory environment. In the current study, we hypothesized that naturally occurring over-ground locomotion, despite “very light” motor effort, as indicated by a Borg scale of 8.0 ± 0.3, likewise causes preexercise activation of the prefrontal cortex. Using wireless NIRS, we examined in this study how early and to what extent prefrontal activity changed before the onset of arbitrary walking in 13 subjects. Prefrontal Oxy-Hb increased 2 s before the onset of arbitrary walking, and the increased Oxy-Hb reached a peak at 5 s from walking onset. The preexercise and initial increase in prefrontal Oxy-Hb was absent when over-ground walking was forced to start by cue. The difference in the Oxy-Hb response between arbitrary and cued start, which was considered to be related to central command, became significant 2 s before walking onset, preceding the difference in the heart rate (HR) response by 8 s. This demonstrated a positive relationship with the HR difference in 69% of subjects. Imagery of arbitrary walking was, likewise, able to increase prefrontal oxygenation to the same extent as actual walking. Thus, it is likely that prefrontal oxygenation increases before the onset of naturally occurring walking in daily life, despite “very light” effort. The increased prefrontal oxygenation may contribute at least partly to cardiac adjustment, synchronized with the beginning of motor performance. NEW & NOTEWORTHY We found using wireless near-infrared spectroscopy that prefrontal oxygenation increased before the onset of arbitrary over-ground walking, whereas the preexercise increase was absent when walking was suddenly started by cue. The difference in prefrontal oxygenation between start modes (considered related to central command) preceded heart rate response variances and demonstrated a positive relationship with the difference in heart rate. The central command-related prefrontal activity may contribute to cardiac adjustment, synchronized with the beginning of overground walking.
AB - Our laboratory has reported with near-infrared spectroscopy (NIRS) that prefrontal oxygenated-hemoglobin concentration (Oxy-Hb), measured as index of regional cerebral blood flow, increased before and at the onset of arbitrary (i.e., noncued) ergometer exercise in a laboratory environment. In the current study, we hypothesized that naturally occurring over-ground locomotion, despite “very light” motor effort, as indicated by a Borg scale of 8.0 ± 0.3, likewise causes preexercise activation of the prefrontal cortex. Using wireless NIRS, we examined in this study how early and to what extent prefrontal activity changed before the onset of arbitrary walking in 13 subjects. Prefrontal Oxy-Hb increased 2 s before the onset of arbitrary walking, and the increased Oxy-Hb reached a peak at 5 s from walking onset. The preexercise and initial increase in prefrontal Oxy-Hb was absent when over-ground walking was forced to start by cue. The difference in the Oxy-Hb response between arbitrary and cued start, which was considered to be related to central command, became significant 2 s before walking onset, preceding the difference in the heart rate (HR) response by 8 s. This demonstrated a positive relationship with the HR difference in 69% of subjects. Imagery of arbitrary walking was, likewise, able to increase prefrontal oxygenation to the same extent as actual walking. Thus, it is likely that prefrontal oxygenation increases before the onset of naturally occurring walking in daily life, despite “very light” effort. The increased prefrontal oxygenation may contribute at least partly to cardiac adjustment, synchronized with the beginning of motor performance. NEW & NOTEWORTHY We found using wireless near-infrared spectroscopy that prefrontal oxygenation increased before the onset of arbitrary over-ground walking, whereas the preexercise increase was absent when walking was suddenly started by cue. The difference in prefrontal oxygenation between start modes (considered related to central command) preceded heart rate response variances and demonstrated a positive relationship with the difference in heart rate. The central command-related prefrontal activity may contribute to cardiac adjustment, synchronized with the beginning of overground walking.
KW - Central command
KW - Mental imagery of walking
KW - Over-ground walking
KW - Prefrontal oxygenation
KW - Wireless near-infrared spectroscopy
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U2 - 10.1152/japplphysiol.00392.2020
DO - 10.1152/japplphysiol.00392.2020
M3 - Article
C2 - 32969778
AN - SCOPUS:85096456696
SN - 8750-7587
VL - 129
SP - 1161
EP - 1172
JO - Journal of applied physiology
JF - Journal of applied physiology
IS - 5
ER -