The Role of Exercise-Induced Arousal and Exposure to Blue-Enriched Lighting on Vigilance

Abstract

It is currently assumed that exposure to an artificial blue-enriched light enhances human alertness and task performance, but recent research has suggested that behavioral effects are influenced by the basal state of arousal. Here, we tested whether the effect of blue-enriched lighting on vigilance performance depends on participants’ arousal level. Twenty-four participants completed four sessions (blue-enriched vs. dim light × low vs. high arousal) at 10 pm on four consecutive days, following a repeated-measures design. Participants’ arousal was manipulated parametrically through the execution of a cycling task at two intensities (low vs. moderate), and was checked by monitoring their heart rate. On each session, distal and proximal skin temperatures were recorded as a neuroergonomic index of vigilance, while participants performed a 20-min psychomotor vigilance task (PVT) under either blue-enriched light or dim light conditions. The Positive and Negative Affect Schedule (PANAS), Karolinska Sleepiness Scale (KSS), and Borg Rating of Perceived Exertion Scale (RPE) were used to measure subjective psychological state. The results showed that the exercise-induced manipulation of arousal produced robust alerting effects in most measures, while the lighting manipulation only attenuated subjective sleepiness and enhanced positive affect, but it did not influence behavior or physiology. Acute exposure to a blue-enriched light was practically ineffective when the arousal level was over baseline. The present research favored the use of acute physical exercise over acute exposure to blue-enriched lighting in order to boost humans’ alertness when necessary, as in work settings where maintaining optimal levels of attention is difficult (shift work, night-work, vigilance tasks) and necessary to prevent human error and accidents.

Action monitoring fails when motor execution is too fast: no time for correction

“…Exercise generated a clear peripheral effect which essentially explains the reduction of the RTs in the exercise condition: MTs were reduced at exercise while PMTs were not (see also Beyer et al [17] or similar results in another type of conflict task). This MT reduction might be due to an increase of global muscle tone at exercise, likely driven by the higher arousal state usually induced by exercise ( [36] for an illustration of arousing effects of exercise); note that, conversely, at lower arousal states generated by one night sleep deprivation, MTs are lengthened while PMT are not [37]. If exercise induces a higher basal muscle tone, once motor units are recruited, the response threshold is reached earlier.…”

Action monitoring fails when motor execution is too fast: no time for correction

“…This MT reduction might be due to an increase of global muscle tone at exercise, likely driven by the higher arousal state usually induced by exercise (e.g. Barba et al, 2018 for an illustration of arousing effects of exercise); note that, conversely, at lower arousal states generated by one night sleep deprivation, MTs are lengthened while PMT are not (Ramdani et al, 2013). If exercise induces a higher basal muscle tone, once motor units are recruited, the response threshold is reached earlier.…”

Constant Light Exerted Detrimental Cardiovascular Effects Through Sympathetic Hyperactivity in Normal and Heart Failure Rats

“…Environmental stimuli have a universal influence on humans. Environmental light can greatly affect health in a time-, wavelength-, and intensity-related manner (Tapia-Osorio et al, 2013;Alves-Simoes et al, 2016;Barba et al, 2018). Prolonged light exposure is increasingly popular among modern humans (Daugaard et al, 2019).…”