Kim Kyungshil, Yokosawa Koichi, Okada Ken, Onishi Hayate, Tan Yumiko, Lee Sang-Il
Faculty of Medical and Health Sciences, Hokkaido Bunkyo University, 196-1 Kogane-Chuo 5-Chome, Eniwa, Hokkaido, 061-1449, Japan.
Faculty of Health Sciences, Hokkaido University, Kita 12, Nishi 5, Kita-Ku, Sapporo, Hokkaido, 060-0812, Japan.
J Physiol Anthropol. 2025 May 22;44(1):15. doi: 10.1186/s40101-025-00395-6.
Exposure to short-wavelength light (i.e., blue light) has been shown to enhance cognitive function in humans. While most prior studies have focused on visuospatial working memory, the effects of blue light on auditory working memory, particularly tasks involving the phonological loop, remain underexplored. This study investigated both the during- and post-exposure effects of blue light on auditory memory performance.
Fifteen healthy university students (13 males, 2 females; 21.47 ± 1.06 years old) participated in a randomized crossover design. Each participant was exposed to three lighting conditions for approximately 20-min: blue (λ = 476 nm, illuminance = 21.84 lx, 13.8 log photons/s-1.cm-2, melanopic EDI = 169.68 lx), amber (λ = 580 nm, illuminance = 61.65 lx, 13.5 log photons/s-1.cm-2, melanopic EDI = 2.87 lx) and dim light (baseline; illuminance < 5.00 lx). Each session was separated by a one-week washout period. To mitigate order effects, the sequence of light conditions was randomized across participants. The modified version of the Sternberg working memory task was performed during light exposure and after a 10-min break (i.e., During- vs Post-exposure phase). The accuracy, reaction time, subject anxiety and subject sleepiness were measured.
In the post-exposure phase, blue light significantly improved accuracy compared to amber (p < 0.01, d = 0.66) and dim light (p < 0.01, d = 0.67). No significant differences were observed during exposure or in reaction time across three light conditions. Anxiety levels were significantly higher during blue light exposure (vs. amber: p = 0.013, d = 0.96; vs. dim: p = 0.027, d = 0.83), while sleepiness remained unchanged.
Blue light exposure may enhance auditory working memory accuracy with a delayed effect, independent of vigilance or processing speed. While these findings are promising, the observed effects are preliminary and require validation in larger and more diverse populations.
已表明暴露于短波长光（即蓝光）可增强人类的认知功能。虽然大多数先前的研究都集中在视觉空间工作记忆上，但蓝光对听觉工作记忆的影响，特别是涉及语音回路的任务，仍未得到充分探索。本研究调查了蓝光对听觉记忆表现的暴露期间和暴露后的影响。
15名健康大学生（13名男性，2名女性；年龄21.47±1.06岁）参与了随机交叉设计。每位参与者在三种光照条件下暴露约20分钟：蓝光（λ=476nm，照度=21.84勒克斯，13.8对数光子/秒·平方厘米，黑素视蛋白等效日光照度=169.68勒克斯）、琥珀光（λ=580nm，照度=61.65勒克斯，13.5对数光子/秒·平方厘米，黑素视蛋白等效日光照度=2.87勒克斯）和暗光（基线；照度<5.00勒克斯）。每节之间间隔一周的洗脱期。为减轻顺序效应，光照条件的顺序在参与者之间随机分配。在光照期间和10分钟休息后（即暴露期间与暴露后阶段）进行修改版的斯特恩伯格工作记忆任务。测量准确性、反应时间、受试者焦虑和受试者困倦程度。
在暴露后阶段，与琥珀光（p<0.01，d=0.66）和暗光（p<0.01，d=0.67）相比，蓝光显著提高了准确性。在三种光照条件下的暴露期间或反应时间上未观察到显著差异。蓝光暴露期间焦虑水平显著更高（与琥珀光相比：p=0.013，d=0.96；与暗光相比：p=0.027，d=0.83），而困倦程度保持不变。
蓝光暴露可能会延迟增强听觉工作记忆准确性，且与警觉性或处理速度无关。虽然这些发现很有前景，但观察到的效应是初步的，需要在更大且更多样化的人群中进行验证。
