Sensory overload and photic sneezing – plus some brain food for the road

Seasonal Cheer or Sensory Overload?

The Festive Season is packed with crowded streets, bright lights and unpredictable surprises in unfamiliar places, all things that send people with sensory processing disorders into a spin. Current estimates suggest that one in six of us are ‘on the spectrum’ – Visual Sensory Experiences From the Viewpoint of Autistic Adults, and one in 36 children are diagnosed with Autism Spectrum Disorder, up from one on 44 just six years ago – Data & Statistics on Autism Spectrum Disorder.

There is growing evidence of the biological basis of these differences and the critical role of vision and light in creating places and situations where everyone can relax and feel at home.

For example, differences in the CLOCK gene expression affects sleep and arousal hormones such as cortisol and melatonin. They are more likely to suffer from sleep disorders, linked to depression and mood swings, difficulty managing emotions and communicating clearly – Biological correlates of altered circadian rhythms, autonomic functions and sleep problems in autism spectrum disorder. So they need even more help than the rest of us from a regular cycle of bright days and dark nights to set their body clocks.

This group autism also experience ‘tunnel vision’, with a very sharp drop off towards the edges of a scene – Tunnel Vision: Sharper Gradient of Spatial Attention in Autism. It takes them longer to disengage and redirect their attention – The spatial extent of focused attention modulates attentional disengagement, and their ability to spot subtle changes that go unnoticed by ‘neurotypical’ people mean that fast-moving or unpredictable situations trigger the kind of anxiety that others might experience on a roller-coaster ride – Differences in change blindness to real-life scenes in adults with autism spectrum conditions.

So what can we all do, as family and friends, colleagues and hosts to make everyone feel relaxed and welcome? This rare study invited adults with Autism to talk about what works for them – Visual Sensory Experiences From the Viewpoint of Autistic Adults.

1. Keep it soft: this study suggests that dim light is most comfortable for most, but offer task lighting for those who need it.
2. Keep it simple: strong colours and patterns are distracting and even distressing, especially in stressful social settings. Choose calm colours with low-contrast, regular patterns and avoid sparkling or flashing lights.
3. Offer space to reset. I suffered from sensory overload for many years myself and still do from time to time. I got used to asking the host in advance if I could take a 20 minute break when I arrived before joining the group. 

They never said ‘no’, and of course, neither would you.  A little bit of planning can really help the host as well as you to relax and make the most of the time together. 

Dining out? Make sure the lighting’s right!

Over one in six of British people will go out for Christmas lunch this year according to this study. 23% of those say it’s because they just don’t want to cook – New Survey Reveals UK Residents Want Christmas Dinner in a Restaurant this Year. If you’re booking your table, check the lighting is right: it can lure you into a venue, shift how tasty you find the food and even what you think of the service itself. 

1. Dim high-level lighting with focal lighting is perceived as more attractive if we’re dining with friends and family. We will choose a more uniform look if we’re eating with colleagues or people we don’t know so well – In darkness we seek light: The impact of focal and general lighting designs on customers’ approach intentions toward restaurants.
2. We find complex flavours more intense in a brighter setting – On the bright side: The influence of brightness on overall taste intensity perception, while food with a simpler profile (sweet or salty) are tastier in dim light – Less light, better bite: How ambient lighting influences taste perceptions.
3. Another study found improved satisfaction and perceived service quality in red or yellow lighting compared to blue and green – The Influence of the color of light on the customers’ perception of service quality and satisfaction in the restaurant.

But it’s clear the lightbulb won’t work alone: the decor, especially the tablecloth, affects how long you’ll stay, how much you’ll eat and how much you’re willing to pay – The impact of lighting and table linen as ambient factors on meal intake and taste perception.

Podcasts for the road

Millions of us will set off to visit friends and family next week.

I always download a podcast or webinar to keep my brain on the move. Here are three for your playlist.

1. A masterclass from Mary Carscadon, the grand dame of sleep and teens – Development of sleep and circadian rhythms across adolescence.
2. A fascinating conversation from the Huberman lab with the wonderful Samer Hattar – Timing Light, Food, & Exercise for Better Sleep, Energy & Mood | Huberman Lab #43

3. And a glimpse of the future and sustainability with this Get a Grip on Lighting podcast with Mike Johnson and the International Living Future Institute (ILFI) – #331 Everything’s Connected.

Pub Quiz factoids

Why do some people sneeze in bright light?

Up to 35% of us get the “photic sneeze reflex,” a heritable condition that results in sneezing when we’re exposed to a blast of bright light, particularly after adaptation to darkness. A sudden rise in temperature as you come in from the cold leads to condensation in your nose – just like the fog on your glasses or the windscreen of your car. That irritation compounds the problems caused by the sudden glitchy cross-talk between two of the most important nerves that run around your skull.

When you’ve recovered from the antisocial spluttering, you can boast that you’re manifesting the mysterious trigeminocardiac reflex (TCR) – Photic sneeze reflex: another variant of the trigeminocardiac reflex?