Ever feel like your brain is buffering — even after your favorite cup of matcha? You sit down to work, but your focus drifts, your ideas seem uninspired, and by mid-afternoon, your mental energy feels completely drained.
If that sounds familiar, the culprit might be closer than you think: your lighting.
We routinely flip on overhead LEDs, stare at screens for hours, and spend most of our lives bathed in artificial light. Yet our brains evolved under natural sunlight—an environment that shifts in color and intensity throughout the day to help regulate our hormones, neurotransmitters, and circadian rhythms. Modern artificial lighting, however, bombards us with unbalanced wavelengths that can disrupt sleep, dull focus, and stifle creativity.
How Light Shapes Brain Function
Light is more than just illumination; it serves as critical information for your brain. The color, quality, and timing of your light exposure affect:
Dopamine and serotonin levels: These neurotransmitters influence your mood, motivation, and attention.
Melatonin production: This hormone governs sleep quality and plays a key role in memory consolidation.
Circadian rhythm: Your internal clock, which orchestrates sleep, wakefulness, and many bodily functions.
Natural sunlight offers full-spectrum light—comprising a balanced mix of blue, red, and infrared wavelengths—that keeps your brain’s functions in harmony. In contrast, artificial lighting (especially from LEDs, fluorescents, and digital screens) floods the brain with excessive blue light while lacking the complementary red and infrared wavelengths that help mitigate its effects.
For example, excessive blue light exposure during the evening suppresses melatonin production, delaying sleep and impairing memory consolidation (Alkozei et al., 2019). Meanwhile, staying indoors in low-light conditions can result in decreased levels of dopamine and serotonin, contributing to brain fog and reduced cognitive flexibility (Lazzerini Ospri et al., 2017).
Moreover, many modern light sources exhibit flicker—rapid fluctuations in brightness that, even when imperceptible, can stress the nervous system, leading to headaches, fatigue, and concentration problems (Sánchez-López et al., 2019).
How Artificial Light Impacts Memory and Focus
The formation of memory and sustained focus depend on restorative sleep and a well-regulated circadian rhythm. Artificial lighting interferes with these processes in several ways:
Daytime blue light overexposure can lower dopamine levels, reducing motivation and impairing focus.
Nighttime light exposure delays melatonin release, leading to poor sleep.
Poor sleep impairs the glymphatic system—your brain’s natural detox system—, which is responsible for clearing out waste, accumulated during waking hours. If this system is disrupted, memory retention and learning suffer (Xie et al., 2013; Yuan et al., 2023).
Why Creativity Suffers Indoors
Have you ever noticed that your best ideas often occur when you are out in natural light, taking a walk, or relaxing in a calm space? This is not coincidental. Natural light promotes alpha brain wave activity, which is linked to a more creative, open, and relaxed mental state (Giménez et al., 2019).
Conversely, harsh indoor lighting tends to increase beta brain waves—associated with analytical thinking. While helpful for focus, an overactive beta state can suppress creative ideation and make it harder for the brain to connect concepts and generate new ideas.
In addition, because dopamine is key to creative flow, the dopamine-depleting effects of artificial light may leave you feeling uninspired by day’s end.
How to Optimize Your Light for Better Brain Function
You do not need to abandon modern life to support your cognitive health. These small lighting shifts can make a significant difference:
Start your day with natural sunlight
Just 10–15 minutes of morning, sun helps set your circadian rhythm and elevate serotonin.
Work near windows or use full-spectrum lighting
If natural light is not an option, full-spectrum bulbs offer a more brain-friendly alternative to typical LEDs.
Ditch blue light after dark
Use warm, amber-toned bulbs at night and reduce screen time as the evening progresses.
If you cannot avoid screens (hello, real life), wear blue light–blocking glasses after sunset to help reduce melatonin suppression and ease the transition into rest mode.
Take daylight breaks
Step outside or into naturally lit spaces throughout the day to give your brain the light variation, it craves. Even a few minutes of sun can reset your mood and mental clarity.
Key Takeaways
Your lighting environment may seem like a minor detail, but it plays a major role in how clearly you think, how well you sleep, and how creative you feel. Artificial lighting has real cognitive consequences—from neurotransmitter imbalance and sleep disruption to impaired memory and dulled creativity.
Before you reach for another productivity hack, consider this: sometimes the clearest mind starts with brighter mornings, fewer screens at night, and more natural light throughout your day.
I share simple, science-backed tips on Instagram each week to help you feel better, think clearer, and live more aligned. Follow along for more on light, lifestyle, and functional medicine.
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References
Alkozei, A., Smith, R., Pisner, D. A., Vanuk, J. R., Berryhill, S. M., Fridman, A., … & Killgore, W. D. (2019). Exposure to blue light increases subsequent functional activation of the prefrontal cortex during performance of a working memory task. Sleep Health, 5(1), 55–65. https://doi.org/10.1016/j.sleh.2018.09.007
Bedrosian, T. A., & Nelson, R. J. (2017). Timing of light exposure affects mood and brain circuits. Translational Psychiatry, 7(1), e1017. https://doi.org/10.1038/tp.2016.262
Chellappa, S. L., Steiner, R., Oelhafen, P., Lang, D., Götz, T., Krebs, J., … & Cajochen, C. (2013). Acute exposure to evening blue-enriched light impacts on human sleep. Journal of Sleep Research, 22(5), 573–580. https://doi.org/10.1111/jsr.12050
Giménez, M. C., Kantermann, T., & Cajochen, C. (2019). The impact of light on brain function. Frontiers in Neuroscience, 13, 1289. https://doi.org/10.3389/fnins.2019.01289
Lazzerini Ospri, L., Prusky, G., & Hattar, S. (2017). Mood, the circadian system, and melanopsin retinal ganglion cells. Annual Review of Neuroscience, 40, 539–556. https://doi.org/10.1146/annurev-neuro-072116-031324
Sánchez-López, A., Cuesta-Frau, D., & Alesanco, Á. (2019). Flicker perception and EEG: The human brain’s response to LED lighting. International Journal of Environmental Research and Public Health, 16(12), 2148. https://doi.org/10.3390/ijerph16122148
Walker, M. P. (2017). Why we sleep: Unlocking the power of sleep and dreams. Scribner.
Xie, L., Kang, H., Xu, Q., Chen, M. J., Liao, Y., Thiyagarajan, M., … & Nedergaard, M. (2013). Sleep drives metabolite clearance from the adult brain. Science, 342(6156), 373–377. https://doi.org/10.1126/science.1241224
Yuan, Z., Liu, Z., Qi, J., Cheng, Y., Li, Y., & Yu, X. (2023). The impact of artificial light exposure on human circadian rhythms, sleep, and cognitive performance. Frontiers in Neuroscience, 17, 1116573. https://doi.org/10.3389/fnins.2023.1116573
Yours in health,
Katherine Roy, MS, APRN, FNP-C
