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This is for all Groundhogs out there…

Groundhog Day? Things are not what they seem!

As we put our shoes back on and get ready for the new season, it can seem as though nothing has changed since you last logged into the world of lighting. And yet, there has been a quiet revolution going on and even some rowdy disagreement in the normally staid and silent corridors of science.

Here’s one debate you might have missed while you were slapping on the suntan lotion/repainting the fence/hosting sleepovers for the kids/juggling the in-box/feeding the neighbour’s cat…

That’s the unravelling of the melatonin-sleep connection. I was privileged to host a workshop with Professor Russell Foster in May. He pointed out that although melatonin levels may be, in his words, a ‘marker of the dark’ – and play a valuable anticipatory role in sleep onset – New perspectives on the role of melatonin in human sleep, circadian rhythms and their regulation, higher levels do not directly equate to more, or even deeper sleep – objectively at least.

Here is a link to the recording, transcript and slides if you, like me, prefer to skim before committing your ears – Common Ground, Principles and Practice for Lighting in Residential HealthCare Oxford 11 May 2023

This paper published in July this year is one of a growing number that suggest that melatonin is not the golden ticket for a blissful snooze and that we need to consider a two – The two-process model of sleep regulation: a reappraisal or even a three-part model that integrates sleep pressure (how long you’ been awake) with timing and duration of light exposure – and emotional factors too.

For example, comparing melatonin levels of people experiencing Fibromyalgia who subjectively experienced a very poor nights’ sleep and ‘normal’ subjects and found no difference between them Subjective Sleep Quality Versus Objective Accelerometric Measures of Sleep and Systemic Concentrations of Sleep-Related Hormones as Objective Biomarkers in Fibromyalgia Patients

If you’d like to learn more- and earn CPD Credits too! – please join the first Introduction to Human-Centric Lighting: principles and practice course online via zoom on Friday 22nd of September from 4 -5:30pm. More information is here.  I’m planning more half-hour sessions too – so do get in touch if you’re interested but that date doesn’t suit.


Video call tips 

Working from home today? Here are three common mistakes and three simple tips so that you can set up the lighting to be more confident and comfortable on video calls in just 60 seconds!

If you sit with the window in front of you, you get a gorgeous view and loads of natural light which is great for your mood and body clock. The trouble is that your eyes struggle to cope with the contrast between the screen and the sky and your workspace is shadow.

Sitting with the window behind you isn’t great either! Your face will be in shadow and you’ll get lots of reflections on the screen which is really tiring for your eyes.

Ring lights may look glamorous, but they’re designed to be used in short bursts for fashion shoots – they’re really bad for your eyes if you’re staring at them for hours on end – plus they make lots of distracting reflections on your glasses.

The solution? Put your desk at right angles to the window, on wheels so you can move it, with your monitor on an arm so you can adjust for reflections. Add a lamp on the opposite side of the window to fill in the shadows to create a balanced, clean, and open connection – your eyes will thank you too!

Hope that helps…


And it’s National Hug Your Hound day on Sunday in the USA.

My brother’s beagle Mister Binks is his pride and joy – and Bella, Stan, Ozzie, Rolo, Mr Tonks, Diesel and so many others keep their two-legged friends sane. Their amazing sense of smell (an estimated 10,000 times better than you and I) means that can cope better than we do when their eyesight starts to fail. This paper is full of fascinating factoids – for example around 12% of each breath goes directly to the brain – and they can detect direction from subtle differences between their left and right nostrils! – Canine Olfaction: Physiology, Behavior, and Possibilities for Practical Applications

Anyone who has watched a dog out on a walk will feel that they can see with their noses – it turns out they literally can – signals from their nose are integrated with the visual and other cortices in a way that has not been traced in any other animal before – Extensive Connections of the Canine Olfactory Pathway Revealed by Tractography and Dissection.

Another reason to give your hound a hug – or hug someone else’s!

Get in touch!