What do psychology and neuroscience tell us about what architects should promote or avoid in facade design? Eleanor Young speaks to two experts
When Thomas Heatherwick launched his ‘anti-boring’ campaign in 2023, rapidly followed by a BBC Radio 4 series, Building Soul, and his book, Humanise, it felt like another bit of architect-bashing, this time from this designer extraordinaire who has made it his business to go beyond sculptures and buses to design buildings – with an expressive gin distillery and Google’s UK headquarters among his achievements.
Yet two new academic studies using biomarkers and carefully controlled experiments to understand the impact of facades on the people around them have shown that architects have the opportunity to improve wellbeing with the outsides of their buildings.
In the emerging fields of architectural psychology and architecture neuroimmunology, the impact of buildings is being unravelled with experiments in the lab and on the street. They are the missing link between the best architects’ professional instinct about the impact of buildings and understanding how visual stress and lack of arousal (boring design, as Heatherwick would have it) can contribute to negative public health outcomes.
I spoke to Colin Ellard, a psychologist at Canada’s University of Waterloo, and Cleo Valentine, a researcher and systems designer at the University of Cambridge who specialises in architectural neurophysiology and bioethics. (Valentine is also senior research and innovation lead at the UCL/RISE Centre for NeuroArchitecture and NeuroDesign, RISE Research Institutes of Sweden). Both have undertaken studies on facades, supported by Heatherwick Studio, adding specific facade focus to their wider work on the psychology and neuroscience of our built environment.
They explain how architecture can strongly contribute to allostatic overload, so when we perceive a threat, the stress it creates releases cortisol and other stress hormones. This shifts our systems to the sympathetic nervous system – fight or flight. With regular or chronic stress this cascades through our systems, taking its toll on our body’s systems and, in response, produces an inflammatory response in the brain and body. This has been linked to a huge number of ailments, from cardiovascular and coeliac disease to allergies and arthritis.
Ellard adds that the psychological impact of not engaging with our surroundings – the absence of arousal – can lead to self-harming and addictive behaviours. This has been noted by the extended science of boredom (from James Danckert, among others).
So, to the two studies. Both concentrated on analysing reactions to buildings of different facade complexity, as analysed by fractal geometry and visual stress. Ellard’s study used walking tours around London and Toronto to take in six buildings for five minutes each, taking 100 people around, one at a time. Participants were monitored using mobile sensors for skin conductance – an established method for measuring levels of arousal – as well as questionnaires. The images of the buildings they were asked to take in had been analysed for visual complexity using the FracLac plugin for ImageJ, with subjective reports of complexity used to corroborate the software analysis.
‘Low complexity buildings were perceived to be highly boring and unattractive,’ says Ellard, ‘while high complexity buildings were rated as being interesting and attractive. Our findings demonstrate that boring, low complexity buildings are not merely an aesthetic concern – they can affect people at a raw, physiological level.’
Ellard’s study is unusual in that it takes the study out onto the street – a complex place for experiments but one where he thinks there may be stronger reactions than in the lab when participants are just showed images.
Valentine’s research (see page 52) has found that visual stress is related to high-contrast, visually repetitive patterns, ‘fundamentally those that are as far from nature as possible’. Her findings are awaiting peer review before full academic publication.
The work of both Ellard and Valentine has already made some impact on architects. Ellard recalls architect friends ‘yelling’ at him after he talked about some of his findings.
Valentine remarks: ‘Some architects may feel a scientific approach is prescriptive – as if it’s trying to dictate a building’s design. But science currently cannot define an optimal building. Instead, we’re aiming to identify specific features that may cause harm, so we can better understand their impact and avoid unintended consequences.’
There is solid evidence, they both agree, that the cumulative effect of high-frequency grading – regular repetitive patterns – is a negative one. ‘I have every sympathy with architects who don’t want to be coded out of existence,’ says Ellard, ‘but it is a social responsibility.’
So what should architects should be aiming for? Drawing on his wider experience, Ellard recommends awe, ‘which is similar to when people experience natural splendour’. Ellard also acknowledges that buildings that have stood the test of time often seem to elicit a positive response – a harder thing to design in, but not impossible.
Neurophysiological responses by Cleo Valentine
Our research at the University of Cambridge explores the intersection of architectural design, neuroscience and human health. We are investigating how architectural facades affect neurophysiological responses, with a particular interest in understanding the relationship between visual patterns and forms in building facades and measurable changes in brain activity and stress responses.
Our interest in this field stems from compelling evidence that humans have evolved to efficiently process natural visual scenes, which follow specific statistical patterns such as the 1/f amplitude spectrum (Wilkins, A. (2016). A physiological basis for visual discomfort: Application in lighting design. Lighting Research & Technology, 48(1), 44–54). Modern architectural environments often deviate significantly from these natural patterns, potentially creating visual environments that our brains find inefficient to process. When buildings feature high-contrast, repetitive patterns, they may induce visual discomfort and physiological stress in viewers (Wilkins, A. J., et al. (2018). The Built Environment and Its Patterns: A View From the Vision Sciences).
To contribute to this emerging field, we employ an integrated methodology combining computational analysis, clinical biomarkers and advanced data-processing techniques. Our computational approach uses Fourier spectral analysis (Penacchio, O., & Wilkins, A. J. (2015). Visual discomfort and the spatial distribution of Fourier energy. Vision Research, 108, 1–7) which allows us to quantitatively assess architectural images by breaking them down into their component spatial frequencies. This reveals the underlying visual structure of building facades and helps identify patterns that may cause neural strain.
We complement this computational analysis with clinical measurements using functional near-infrared spectroscopy (fNIRS) and heart-rate variability (HRV). The fNIRS technology uses light in the near-infrared spectrum to measure changes in blood oxygenation in the brain, providing a non-invasive window into neural activity when participants view different architectural designs. Simultaneously, HRV monitoring measures the subtle variations between heartbeats, offering insights into autonomic nervous system responses and physiological stress levels. Together, these biomarkers allow us to observe real-time physiological reactions to visual architectural stimuli.
By elucidating the connections between design elements and physiological responses, this approach aims to enrich architectural practice and drive innovations that enhance public health.
Enlisting brain-mapping technology
The US-based Allen Institute has just finished mapping the brain and its many, many cell types and neurons, and shared it freely with the world. So it is not surprising that Thomas Heatherwick has continued his campaign to make more human buildings through a partnership with the institute.
Its president and chief executive Rui Costa explains that the visual cortex (just mapped) shows that when the brain can predict something, it does so and then stops paying attention. The inhibitory neurons cancel out the lively work of pattern recognition, he explains. ‘Novelty makes us move, both mentally and physically,’ he says with excitement.
He wants the city to draw us into it but we need to screen shapes (as we would drugs) to understand their effects. The technology of brain science that can measure electrical activity in the brain is now moving out of the lab and into the street with mobile EEGs. These can measure more real-life interactions which can add depth and a level of distance to opinions that often define how we understand reactions.
Heatherwick and the team behind his Humanise campaign are already looking at not just the public conversation but also how a planning policy might be framed to focus attention.
‘They should hold attention for the time it takes to pass a building,’ says Heatherwick. ‘We have that embedded in planning for the city and street distance, but not for the door distance, up close ... this is about everyday buildings.’