The power of light to change your world for good
Light Notes banner

It’s National Clean your Desk day

Time to tidy up the digital and analogue desktop and give it a clean.

Fire up your video call software and check your background there too.

Here’s why:

  1. Visual clutter makes it harder to focus (and it gets worse with age!) – Differential effects of mind-wandering and visual distraction on age-related changes in neuro-electric brain activity and variability.
  2. Visual distraction reduces your ability to remember facts clearly – Neural Mechanisms Underlying the Impact of Visual Distraction on Retrieval of Long-Term Memory.
  3. Cluttered backgrounds on video calls make it harder for others to concentrate on what you have to say too – What’s that in your background?: The Effects of Visual Clutter on Videoconferencing.
  4. Grubby screens increase glare and reflections, increasing risk of digital eye strain, neck and back pain – Discomfort glare and psychological stress during computer work: subjective responses and associations between neck pain and trapezius muscle blood flow.
  5. A space that feels cared-for boosts morale, productivity and commitment – Impact of Employees’ Workplace Environment on Employees’ Performance: A Multi-Mediation Model.



People quit their bosses, not their job.

One in three of us are looking for a new job in January – Job Market Review: January 2023And 70% are passive job seekers, open to a better offer if it comes along. Every person who leaves your team takes valuable knowledge and connections and morale takes a hit. Replacing them costs an eye-watering 20 to 213% of their salary – How much does it cost to replace an employee?

Better pay is a surprisingly small part of the picture. According to 19,700 post-exit interviews by the Saratoga Institute, only 12% cited cash alone. Four in five blamed corporate culture and poor fit between skills, expectations and prospects – The 7 Hidden Reasons Your Employees Leave You.

But companies rated as great places to work find it easier to attract and keep the best people, which feeds through to the financial results. Top employer brands outperform the S&P500 by122% on average. Those with the worst reputations underperformed S&P 500 by 29.5% – MEASURING CULTURE IN LEADING COMPANIES.

Can lighting help?

It’s not clear-cut. Results from the lab don’t always translate to the real world and great lighting can’t compensate for a toxic culture, poor air quality and temperature or background noise  Ambiguities regarding the relationship between office lighting and subjective alertness: An exploratory field study in a Dutch office landscapeBright light exposure does not prevent the deterioration of alertness induced by sustained high cognitive load demands.

But there is growing evidence that the right light at the right time really can make a difference.

  1. Light during the day that is be bright enough to set their body clock, improving sleep, mood and productivity – Effects of light on human circadian rhythms, sleep and mood , Circadian-effective light and its impact on alertness in office workers.
  2. Windows and outside views increase satisfaction and improve sleep – and even increase the amount of physical exercise your team will take – Impact of Windows and Daylight Exposure on Overall Health and Sleep Quality of Office Workers: A Case-Control Pilot StudyCeiling lights that mimic skylights can help – Blinded by the light: Occupant perceptions and visual comfort assessments of three dynamic daylight control systems and shading strategies.
  3. But windows can cause glare which triggers headaches and reduced productivity – Test rooms to study human comfort in buildings: A review of controlled experiments and facilitiesSimple mesh shades or more expensive electrochromic glazing will give your team the best of both worlds – Multi-performance optimization of static shading devices for glare, daylight, view and energy consideration.
  4. ‘Cool’ and ‘warm’ lights seem to encourage different kinds of behaviour and thinking styles. People in bright blue-ish light tend to perform better on analytical tasks and visuospatial processing – Effects of new light sources on task switching and mental rotation performance, while yellower lighting encourages more creative, collaborative and consensual strategies – The effects of light illuminance and correlated color temperature on mood and creativity.
  5. But everyone is different, so Simply offering control is the single biggest factor in satisfaction and productivity and a visible signal to your people that you care – Perceived Level of Personal Control Over the Work Environment and Employee Satisfaction and Work PerformanceThe business case for a healthy office; a holistic overview of relations between office workspace design and mental health.



Dream of darkness

The quality of darkness at night is as important the quality of light during the day.

Every 5 lux increase in light exposure after dark was associated with longer time to get to sleep and more disturbed sleep: 7.8 minutes increase in sleep onset and 32% increased risk of irregular sleep onset.

Those effects linger for the next night too – every 5-lux unit increase in LEDS the night prior was associated with a 2.2-min greater deviation of sleep onset the next night – Light exposure during sleep is bidirectionally associated with irregular sleep timing: The multi-ethnic study of atherosclerosis (MESA).

Darkness will help if you’re trying to shift those Christmas calories too. Sleeping with the TV or a light on can increase your risk of obesity by 10% – Association of Exposure to Artificial Light at Night While Sleeping With Risk of Obesity in Women.


Your biceps have their own body clock!

I’ve started to lift weights to keep my old bones strong. I noticed I get (a very little bit!) stronger as the day goes on, with a peak between 4 and 6pm. This article explains why – Effects of Resistance Exercise on Bone Health.

Not only do your muscles take time to ‘warm up’, they also draw on neural pathways that reach their peak later on too. But scientists have just discovered that your muscles have their very own sleep-wake cycle and need to rest. If you go for 36 hours without a good night’s sleep, your muscle strength drops by up to 17% – Time of Day and Muscle Strength: A Circadian Output?

Don’t wait too long to do those bench presses though – working up a sweat less than an hour before bed can make it harder to get to sleep – Effects of Evening Exercise on Sleep in Healthy Participants: A Systematic Review and Meta-Analysis.

Get in touch!