Seeing the wood for the trees
Your brain processes elements of a scene in parallel, then adds them up or integrates them to make meaning – known as ‘Feature Integration’ – A feature-integration theory of attention.
We were born with some ‘priors’ or assumptions about how things usually work in the world – light from above (shadows below), multiple parts of the same thing likely to move together, sound coming from one direction likely to be linked to the biggest object in that position.
Then we fine-tuned that through trial and error, as anyone who has enjoyed playing ‘peek a boo’ with a small child will know.
That integration and updating process becomes seamless and increasingly efficient into adolescence, so that by the time we’re in our early 20’s, we’re using feedback to update the meanings assigned to a set of stimuli without giving it a second thought – Feature integration across the lifespan: stickier stimulus–response bindings in children and older adults.
As we age, those meanings become more ‘sticky’ again, while neurodegenerative diseases like Parkinson’s start to uncouple that feature integration mechanism. While the processing power may still be there, the sense-making starts to slow down: we can spot a single feature (like red), but are slower to bind with other features (like round). Research suggests that people on the autistic spectrum may also experience a similar reduction in speed to bind multiple features to create a perceptual ‘whole’ – Visual integration in autism.
What does that mean for the lights?
Congruence – Lighting gives us the basic data we need to pick out the elements in a scene that matter, cross-referencing the visual with other inputs like sound to iron out ambiguities. The visual pathway dominates in adulthood. But for small children, older adults and people with low vision, it’s sound that comes first. So lighting needs to make it easy to see the main sources of sound – the face of the speaker in a meeting or the teacher in a classroom – facilitating that matching process – Children cannot ignore what they hear: Incongruent emotional information leads to an auditory dominance in children, Perceptions of Audio-Visual Impact Events in Younger and Older Adults.
Consistency – Lighting also needs to align with the basic assumptions – light from above, for example – so that shadows fall in predictable places, stabilising scale and relationships in space. Your ears are performing a similar task, with the brain interpreting subtle differences in volume and split-second delays between the sound reaching your left and right ears as critical clues to location. Spaces with extreme or inconsistent reverberation qualities make it harder to focus on a speaker or hear what they have to say – Effect of reverberation and noise type on speech intelligibility in real complex acoustic scenarios.
Contrast – Uniformity is important for reading facial expressions for example, but lighting is also an important tool to create contrast so that people, objects and elements like steps and doorways can be picked out against the background. Light Reflectance Value is ‘the total quantity of visible light reflected by a surface at all wavelengths and directions when illuminated by a light source” – Light reflectance value. It ranges from 0 (matt black/no reflection) to 100 (mirror finish/white/all the light is reflected), with a difference of 30 points adopted as the minimum in public spaces in the UK – Light reflectance value. Here again, working with the accoustic properties of materials alongside their visual qualities can facilitate orientation as this brilliant blog from BDP explains – Sensory design in hospital environments makes sense.
It was so brilliant to meet Sue Egersdorf at Ready Generations and Pritesh Nathwani of Symphony Sounds and the team at Belong in Chester to build the foundations for a pioneering project that brings together pre-school children and older adults living with dementia. Together we’re looking at simple ways to improve the quality of the visual and acoustic environment to support intergenerational connection and fun.
How are you feeling?
There are dozens of ways to measure ‘wellbeing’, from the simple emoji to a 100-point clinical questionnaire or being wired up for an Electroencephalogram – Current recommendations on the selection of measures for well-being.
While measuring how you feel at any given moment is complex, one thing is clear – the quality of the spaces where you spend your time can make a real difference to your mental health.
IEQ (or Interior Environmental Quality) is the umbrella term for this blend of factors – including lighting and controls, access to daylight and views outside of course 😉 Here are just a few recent papers about that fundamental connection in the office – The business case for a healthy office; a holistic overview of relations between office workspace design and mental health, the home – Can housing conditions and features affect well-being? A review through Indoor Environmental Quality aspects and Mental Health implications, Indoor environmental quality and achieving performance goals for classroom enhancement: A systematic literature review and bibliometric analysis, and healthcare settings, Indoor environmental quality (IEQ) in healthcare facilities: A systematic literature review and gap analysis.
As this recent paper from the EU points out, designing for enhanced IEQ goes hand in glove with enhanced environmental performance and resilience to meet changing future needs. A win-win-win.
While this research may be new, the underlying ideas are not.
The Design in Mental Health Network has been campaigning tirelessly to put these simple principles on the agenda for almost 20 years now now, hosting conferences and webinars, publishing white papers and lobbying government and senior management teams in the construction and related sectors
So it’s a privilege to have been invited to be a member of their Ambassador team, supporting Charlotte Burrows and the rest of the network to make sure that lighting design that actively supports mental health is standard, not the exception to the rule.
Get in touch if you’ve got an idea for a project or collaboration or a case study you’d like to share.
The sound of silence
By the time you see this, I’ll be three days into a 10-day silent retreat in a quiet corner of Herefordshire in the UK.
Although it’s not the first time I’ve done this, I’m still quite nervous.
This is considered the ‘iron man’ of retreats, observing noble silence for the duration of the event – that means no eye contact, speaking or physical touch. No mobile phones, nothing to read or write with either. No food after 12 noon unless by request and definitely no glasses of wine!
I know I’ll miss the swimmer’s grins.
But I won’t miss seeing myself on zoom – The surprising mental impact of seeing your own face on Zoom calls.