Humans are pretty visual creatures; our brains are exquisitely sensitive to light – and consequently, light can affect our mood, energy, sleep, focus, and cognition.
Light considerably impacts our body’s clock – our circadian rhythm. Circadian rhythm and sleep issues are so prevalent in ADHDers that some researchers have called for considering them to be a primary consideration in treating ADHD. While doctors can prescribe Bright Light Therapy for conditions like Seasonal Affective Disorder, lighting affects any human with sight – and armed with that knowledge, you can light up your days and nights in brain-friendly ways!
As the days grow shorter in the Northern Hemisphere, here are seven quick everyday ways to consider how light might be affecting your brain on a daily basis.
Background: What Matters About Light?
- Timing – Our brains are differently sensitive to different kinds of light at different times of the day.
- Duration / Frequency – More time exposed to the light means more effect.
- Intensity – Brighter and more intense light counts as more light. Interestingly, your proximity to a light source affects the intensity, so sitting near a light source is more impactful than sitting far from one.
- Color / Color Temperature – Our brains interpret blue light as daytime and red light as nighttime. Think of a bright blue sky or the glow of an evening campfire. The color of light is described as the color temperature (measured in degrees Kelvin, k). Daylight is around 5500-6500k, while a candle is about 2000k. So, bluer light has a higher color temperature than redder light.
So, how can you use light to talk to your brain?
- Getting sunlight in the morning can help you perk up. Have your coffee outside, or check your email on your porch. If you’re not a morning person, this can help to wake you up and set your circadian rhythm for the day. The key word here is morning – afternoon sun will have less impact on the timing of your circadian rhythm.
- More time outside during the day can actually improve the quality and even the duration of your sleep! If you’re not feeling rested, open the blinds, go for a walk, or swap your overhead bulbs for some daylight bulbs with a bluer color and brighter intensity to help mimic sunlight. Some research suggests that time outside can even protect us from the effects of blue light at night.
- Another way to protect your brain from the effects of blue light after dark is to… watch the sunset. Our eyes have circuits devoted to seeing light change between blue and yellow- something that happens at sunrise and sunset. Those circuits don’t help us see images at all – they only tell us about sunup and sundown. Their only function is to help us determine when the world is transitioning between day and night. So, seeing the sun rise and set can help protect you against incorrectly timed signals your brain might be getting from artificial lights.
- Mood light at night can help you calm down before bed. Switch from brighter overhead bulbs to dimmer, warmer-colored lamps. Get a cozy amber night light to use for the last few minutes before bed. Turn down the brightness on any devices that you’re using after sunset. You can change both the intensity and the color temperature of light to help remind your brain that it’s wind-down time.
- Blue light at night? Cut it out! If you struggle to get sleepy at night (or you’re trying to reset your body clock for an earlier time), try eliminating the blue light… all of it! While modern devices have blue-light reduction features at night, and some glasses have blue-light reducing filters, a pair of amber or red glasses that filter out 99% of blue light will really impact your brain.
- Fluorescent bulbs might not be your friend. Many folks report having poorer focus under fluorescent bulbs, and research backs them up. Fluorescent bulbs flicker and hum and can be overwhelming, so if you can swap them out, great! If you don’t, what about using lamps instead or changing location? Light can help us focus but can also hinder us if the lights are distracting.
- If it’s too bright, remember what matters. If you struggle with light sensitivity (as many ADHDers do), remember that you can get the same effect of a brighter light by increasing the duration or changing the color temperature. Likewise, changing the type of sunglasses you use can impact how much blue light you see and thus affect your circadian rhythm. Even the timing of your sunglasses can matter. So experiment and find ways to use light that works for your unique brain!
Want to learn more about light and the brain? Here are a few sources that I found to be delightful:
Effects of light on human circadian rhythms, sleep, and mood – PMC.
Neuroscience: A Chromatic Retinal Circuit Encodes Sunrise and Sunset for the Brain – ScienceDirect
LED Lighting Color Temperature Strategies for the Home and Office – WGI
Mike Legett
ADHD Coach and Life Coach, Executive Skills Coach