During the Chuseok holiday, you can't avoid traffic congestion. The problem is that long hours of driving cause drowsiness, which can quickly lead to major accidents. In fact, according to the Korea Transportation Safety Authority, the proportion of drowsy driving crashes during holiday periods is about twice as high as usual.
According to several neuroscience studies, drowsy driving is not just simple fatigue but is closely related to changes in brain waves. Brain waves are electrical signals produced by the activity of brain neurons; specific frequency bands increase in drowsy or resting states and decrease in aroused states.
Beta (β) and gamma (γ) waves are active in states of focus and arousal but decrease during drowsiness or rest, while alpha (α), theta (θ), and delta (δ) waves increase in resting or drowsy states. Drowsy driving often involves "microsleep," a very brief lapse into sleep, during which brain wave changes appear as an extreme form of the drowsy or resting state.
In particular, stop-and-go congestion makes the brain more prone to boredom, inducing drowsiness. A research team at the University of Technology Sydney (UTS) in Australia reported in 2023 in the international journal Behavioral Sciences that "an analysis of drivers' brain waves in repetitive, low-variation traffic environments showed a significant increase in theta and delta waves and a decrease in beta and gamma waves." This indicates a drop in the driver's arousal level, creating conditions where drowsiness can set in.
The risk of drowsiness while driving increases with the severity of sleep deprivation. Earlier, in 2016, a joint team from the University of Normandy in France and Maastricht University in the Netherlands confirmed in an on-road experiment that sleep loss triggers brain wave changes that accelerate driver fatigue and drowsiness.
When brain waves were measured during one hour of monotonous highway driving under normal sleep and total sleep deprivation, the sleep-deprived condition showed a tendency for theta and delta waves to increase and beta waves to decrease over time. Actual driving performance also declined, with greater lane-keeping deviation in the sleep-deprived state.
There are also time periods when drowsy driving is especially dangerous. Crash risk is higher right after lunch when blood sugar spikes and between 2 and 4 p.m., when circadian rhythms bring on drowsiness.
To reduce these risks, technologies that use brain waves to prevent drowsy driving are being developed one after another. A research team at the University of California, Berkeley (UC Berkeley) created an earbud prototype that detects drowsiness via brain waves and issues alerts, which it published in Nature Communications. In Korea, Hyundai Mobis is developing technology that measures a driver's brain waves and sends vibrations through the seat to warn when signs of drowsiness appear.
References
Behavioral Sciences (2023), DOI: https://doi.org/10.3390/bs13100788
Biological Psychology (2016), DOI: https://doi.org/10.1016/j.biopsycho.2016.09.010
Nature Communications (2024), DOI: https://doi.org/10.1038/s41467-024-48682-7