The Psychology Behind Perception


Research working towards a Pecha Kucha presentation on the way we perceive our environment, how our senses are stimulated and how this relates to design.


It's split into the following sections:


Reverse Density Lofts in Mitaka, Arakawa & Madeline Gins:

Recently I came across a blog post (by Ingred Fetell Lee) about the Japanese artist Arakawa and his partner, an American poet, Madeline Gins. They worked on numerous projects together in a number of fields: from poetry, philosophy, paintings, conceptual art to architecture. One such project is the Reverse Density Lofts in Mitaka. The couple believed that architecture is an extension to the body, so could therefor be connected to the immune system and be used to promote well-being and health. The apartments were designed with the intention of stimulating the senses in such a way to create a kind of mindfulness and make you feel young.

They do this by challenging the way you navigate around the apartments, the floor is bumpy rising and falling in order to force your body to maintain balance in unusual ways that you are no longer use to as an adult. The apartments are filled with a variety of bright, vibrant colours and unusual textures, giving rise to a great deal of haptic and visual stimuli. The bumpy floors, I imagine, increase your proprioceptive (the sense of one’s own limbs in space) and kinaesthetic (sense of limbs moving and by who) awareness along with your sense of agency (awareness of initiating and executing volatile movements).

All this sensory information is designed to expose the link between our built environment, our sense of self and our bodies, this is something I am keen to explore throughout this blog. From here I hope to research the psychology behind senses and the impact our environment has on us.

The pictures have been taken from this Airbnb listing, I’d love to visit one day.

Eleanoré Delieseies Day & Night light:


For another example of design in which the senses have been acutely observed see this post on my great design blog about Eleanoré Delieseies Day and Night light.

The Uncommon Senses, introduction:

Having looked at examples of how our environment is essentially an extension to our body and there for our mind, and looked at the way it shapes how we think, feel and behave, I’ve decided it would be logical (and interesting) to look deeper into the mechanism by which we perceive the world: our senses.

I’ve been listening to a radio programme, The Uncommon Senses, on BBC Radio 4, in which philosopher Barry Smith investigates the multi-sensory experience we have as human beings. While listening to the radio I’ve been taking notes which I will redraft here with other thoughts and reflections on the subject. Each section is named after the name of the episode which acted as a starting point.

Making Sense of the Senses:


Having looked at the shapes above, if I were to ask you, which is Bouba and which is Kiki? Your answer would be the same as everybody else, it works universally in any language. Everyone always picks the round, curvy, cloud shape as Bouba and the sharp, spiky shape as Kiki. This is known as the Bouba/Kiki effect. We all instinctively know, even babies. Bouba, simply sounds rounder, curvier and more smooth where as Kiki sounds sharp and spiky. The words sound like the shape, it is interesting the way a characteristic such as being spiky, sharp, round or smooth can be transferred from a visual description to an auditory one.

I noticed another interesting level on which this effect works: not only do the words sound like the shape but looking at the shapes of the letters making up the names Bouba and Kiki, we see that the rounder sounding word actually has rounder letters and the spiky sounding word has sharper letters. This is how we have evolved to communicate so well through text, the shapes of letters mimic the way they sound.

Bouba   Kiki

We can also adjust the way we write letters, make them sharper or rounder in order to bias how we react to them. Fonts can have a huge impact on the way we perceive senses. For instance, if you were to taste the wine from a bottle with the label below and on the left, it would taste smooth where as tasting wine from a bottle with the label below on the right would taste sharper, even if it is the same wine in each bottle.


We can adjust the way we taste things using other senses too, apparently if you try taste wine by taking by taking a sip from a glass in one hand and then the other it will taste different (I tried this while drinking a coffee but I couldn’t tell the difference, I suppose this could do with the predictive brain which I will talk about later). Sounds can also change what you taste (again, will go into later).

So this is what interests me, the cross over of senses, the effect one sense can have on another. Another obscure example would be the way odours can actually make things feel softer (such odours exist in shampoo). What I will be looking into, is known as: cross-modal effects.

Traditionally, the belief of us having 5 senses came from the extremely outdated belief that the world is made up of 5 elements:


  • “Ether is the medium through which sound is transmitted thus; the ethereal element is related to the hearing function. The ear, the organ of hearing, expresses action through the organ of speech, which creates meaningful human sound.”
  • “Air is related to the sense of touch; the sensory organ of touch is the skin. The organ of action for the sense of touch is the hand. The skin is especially sensitive and the hand is responsible for the actions of holding, giving and receiving.”
  • “Fire manifests light, heat and color, is related to vision. The eye is the organ of sight, governs the action of walking and is thus related to the feet. For example a blind man can walk, but that walking has no definite direction. Eyes give direction to the action of walking. his is energy, which is converted to colour and light by our eyes. So fire governs our eyes but also gives us direction when we are walking or moving.”
  • “Water is related to the organ of taste, without water the tongue cannot taste. The tongue is closely related in function to the action of the genitals.”
  • “Earth element is related to the sense of smell. The nose is the sensory organ of smell, is related in function to the action of the anus, excretion. The person who has constipation or an unclean colon demonstrates this relationship: he experiences bad breath and his sense of smell becomes dull.”

It is widely accepted that the world is not made up of five elements but in fact many, so why is it not yet widely accepted that we have more senses? If you ask a neuroscientist how many senses we have, then they will tell you somewhere between 22 and 33!

We perceive the world around us through a large combination of senses and most the time don’t even notice the effect one sense might have on another. For instance, imagine being on an aeroplane, you’re in ascent, strapped in and looking up the isle to the flight attendant who is waving her arms about showing you the emergency exits etc. and compare it to if you were looking down the isle in the same way but during decent. Although the image hitting your retina is identical, your brain processes it in such a way that during ascent the cockpit would look higher up and in decent it would look further down, all because the input balance has, it biases the way you see it.

Our experience as humans is governed by a huge number of senses processing huge amounts of data at an incredible rate in ways we struggle to notice. We all experience the sensations from these inputs but perhaps haven’t considered them as a sense. For instance:

Interoception: how you notice internal feelings like butterflies or a change in heart or breathing rate.

Proprioception: the sense of one’s limbs in space.

Kinaesthesia: the sense of a limb moving and who moved it.

Sense of Agency: the sense of control and awareness of initiating and executing volatile movements.

Chemesthesis: the chemical sensibility of the skin and mucous membranes. Chemesthetic sensations arise when chemical compounds activate receptors associated with other senses that mediate pain, touch, and thermal perception. I’ve noticed this before and been curious as to why I can taste toothpaste on my ear or something stupid, so it’s interesting to find out that I’m not tasting it but the cooling sensation is familiar enough to remind me of the taste.

How can we use such senses to improve experiences? We could use chemesthesis when on aeroplanes. The dry air and high altitude means molecules are more diffused so you get less to the nose and your mucus is dry, so instead of tasting the traditional way (odours rising from your mouth to your nose) you could add spice which would stimulate your trigeminal nerve, the fifth cranial nerve, serving your eyes, nose and mouth. Your trigeminal nerve isn’t stimulated by odour so would still work well in dry air.

We all interpret our senses differently, we all have a unique emotional response, a fundamental perception, making it a tricky but fascinating topic to discuss. Next I’ll look at interoception.



The human hearing range lies between 20Hz and 20KHz but it has been found that we can actually detect infrasound (ultra low sonic frequencies below 20Hz) and that these frequencies can have a profound effect on us, we feel the effects from deep within. We feel it in our gut, the same way we have a gut instinct allowing us to make decisions in split seconds as opposed to taking a minute to think about the logical solution. This is because our gut can influence the signal produced by our heart and we have an interoceptive awareness of what going on inside our body (as opposed to exteroception which is to do with the external world).

Think of stock traders, they make an excellent example of how we use gut instinct. It has been shown in a study that traders who are guided by interoceptive sensations are the ones who make more money. Being in tune with their interoceptive sensations allows the to make faster and better decisions. They are able to take a faster emotional read on other people (i.e higher empathy rate) because the human body picks up on small physical changes of other people, this physical change translates directly to the persons emotions. For instance, when someone is sad, their pupils contract, if someone else looks at them, their pupils will also contract: so you’re body state and emotions are embodied by others.

We can quantify ones interoceptive abilities by taking the ratio of their perceived sensation of hear-beat against their actual heartbeat. So obviously it’s a scale of 0 to 1, 0 being hopeless and 1 being 100% in tune (which is beyond human capabilities).

During the second episode of the radio program they carried out an experiment with a hostage negotiator to measure his interoceptive abilities. They speculated that he could either be very good at following an emotional instinct or on the other hand, he could be terrible because he has to follow a rational, logical approach. It turned out that because he has to be a good listener and take an empathetic approach, he scored very well. He scored 0.9 which well exceeds the score required for a “good” rating (0.7).

It has also been observed that marksmen have a high introspective ability as they take the shot between heartbeats resulting in a more precise shot. So our interoceptive abilities means that we can detect things or make decisions before our mind even catches up!

A strange product of our interoceptive skills is that we can detect sounds well below the frequencies we pick up with our ears. There was a scientist who had been experiencing strange sensations and hallucinations in the lab, he eventually realised that it only occurred when a fan somewhere in the basement was on, when it was off, all the odd sensations and hallucinations would go away. It turned out the fan was vibrating at an infrasonic frequency.


This odd phenomena was investigated further at a concert. An infrasonic speaker was set up at the back of the concert hall and the audience were given questionnaire for reporting any odd sensations. At random points throughout the concert they would turn the infrasonic speaker on. The reports of odd sensations from the questionnaires matched up to when the ultrasonic speaker was on. The audience reported things such as:

  • “a shiver down the spine”
  • “a sensation that someone is watching them”
  • “a sense of unease”
  • “a feeling like the washing machine is on”

Organ builders in the 15th and 16th century worked out this strange phenomena and incorporated huge pipes designed to resinate at frequencies below human hearing because they could tell you don’t alway hear sound, you also feel the sound, creating a more engaging, mysterious, visceral experience and giving a sense of awe.



The frequency is generated by the resonance of a tube which vibrates a column of air. I worked out, that if you take a hollow tube, open at both ends, then it will resonate at 20Hz if it is 8.6m long. This can be halved (4.3m) if you close the pipe at one end. This coupled with some kind of oscillator (maybe a bass clarinet mouth piece with it’s reed) could create infrasonic frequencies. This could be exciting to demonstrate in the Pecha Kucha presentation but I will most likely struggle to find time to make it.

The Predictive Brain




If you listen first to the sound above, it will not make any sense to you. It is a recording of a voice but has been heavily manipulated to the degree you cannot understand it. If you then listen to the recording below and then listen to the first recording again, it will make sense. This is the predictive brain.


In the 18th century, philosophers thought that the brain was a “tabula rasa” - a blank slate, on which we slowly process sensory information. This is not true. Our brain works like as a large network, neurons (like a node) are connected by synaptic connections. At anyone time, our brain uses half a million connections. It is constantly processing the sensory information in a closed loop,  it is always second guessing what it expects to come next and comparing it to the input it actually gets.

When you move your eyes the image on your retina jumps about in a jerky, fast sort of manner because your eye moves so rapidly but what you see is a smoothed out version because your brain knows that you are about to move your eye and it smooths the signal. If your eye was to be poked, your brain wouldn’t be expecting it so the image would jump in a jerkier manner.

This second guessing that the brain does is what goes wrong with people who suffer from schizophrenia. A schizophrenic’s brain can’t tell the difference between the external and the internal world, so their brain makes misjudged predictions. This gives rise to hallucinations and other odd side effects like the ability to tickle yourself. If I was to try tickle myself, then my brain would expect what my fingers are doing but a schizophrenic patient tickling themselves wouldn’t have such predictions and would experience it just as if someone else was tickling them.

The predictive brain also allows us to communicate more effectively, you have an expectation of how someone might finish a sentence and in the mean time you are preparing a response. If we can design in a predictive manner, it should allow for a more efficient cognitive process to use what ever it is we are designing making it more user friendly.

If our brain makes too few predictions, then the world would constantly surprise us. If our brain makes too many predictions, then it anticipates what is not true.

Amputees can experience a strange phenomena that occurs because of the predictive brain: they can get cramp or itchy sensations in their missing, “phantom” limb. This is because the brain is not getting the sensory input but it still makes predictions of sensations, so standing on a prosthetic leg would relieve sensations of cramp. We all have phantom limbs, a model of where we think our limbs are, it’s just usually our model coincides with reality.

This model that our brain creates, concerning the position of our limbs and the sensations it expects can also be applied to products (our built environment is an extension to ourselves). When using a product, we have a certain expectation of what the system is, how it works, what we might expect to happen as a result of say flicking a switch, what state it is in, how and what state it transforms to. The designer knows how the system works but the user might not know the system as well as the designer. It is the designers job to communicate the system as effectively as possible, so that the system in the mind of the user reflects the state of the system in reality. For instance, read the post on my great design blog about the hob Mark Newon designed for Smeg, he does it well because the user is easily able to predict which knob turns on which ring (because the hobs and knobs are mapped out naturally), they are easily able to predict the future state of the system as a result of turning a particular knob.



Anyway, back to the psychology. The brain makes assumptions based on what information it receives, so if this information is reduced, degraded, confused or ambiguous, the brain has to go into predictive overdrive to make up for the reduced information and the predictions become less accurate. It’s effectively interpolating data from a reduced sample which will inevitably give less accurate results.



Charles Bonnet Syndrome is a condition that arises in some people who have lost their sight. In order to make up for the lack of information the brain is hungry for more data so instead fills in the gaps with visual hallucinations, the person sees patterns instead of interpreting what is actually in front of them.



As we know, the brain breaks up our environment, senses can overlap and effect our other senses. So it shouldn’t come as a surprise that too much bright light or too much background noise can degrade our ability to taste. Contrarily, we can also use our environment to enhance our sense of taste.

If you were to eat a tuna sandwich in the middle of central station or some busy part of town with lots of noise, people, distractions and lots of grey, then the sandwich would taste pretty bland, perhaps the bombardment of undesirable sensations would be distracting you from the taste . Where as if you were to take the same sandwich to a more quiet, peaceful area, say on a park bench, you’d notice the feeling of the bench on your skin, the gentle breeze, maybe some birds tweeting, you’d feel the texture of the bread as you lift it to your mouth, you’d smell it and be able to pick up on the taste a great deal more, it would be a far more valuable experience.

It can be shown that higher pitched, fast sounds can make something taste sour whereas low rumbles make things taste more bitter. The effect ambiance has on our taste is huge. This is something that has been considered in the design of the Germans Gymnasium (by Terence Conran), a restaurant and cafe in London. As you walk into the building it has high ceilings, it’s flooded with light, there’s the tinkling of glass wear. The cafe has hard, heavy marble tables with light cutlery and thicker glasses, it’s a causal area designed for a quick bite to eat (“based on the european dining experience”). When you walk into the restaurant it is a more formal environment: there is linen soft to the touch on the tables, thinner/finer glass wear, heavier cutlery. This extra consideration enhances the diners experience and allows them to charge a premium.


Dinnertime: A multi sensory extravaganza!


Eating is a multi sensory experience. We see the food, hear it in our mouths, touch/feel it, taste it and smell it all at the same time. The food is never in isolation, it is always in some kind of context, usually on a plate. The plate we eat off of can has impact on the way we experience the food. It’s been shown in a study that a strawberry mouse will taste 7% sweeter, 13% more flavourful and 9% more liked if served on a  round white plate instead of a black plate.



If you take two bowls of yogurt, one with a small, heavy, dense weight hiding below the yogurt and one in a bowl without the additional weight, the heavier bowl tastes richer, creamier and smoother compared to the lighter bowl even though the contents are identical. The heavier one will seem more substantial and of higher quality, people will be prepared to pay more. This theory extends from plates/bowls to cutlery. It is what makes eating off paper plates with plastic cutlery so crap.



Visual, auditory and haptic sensory inputs each go to a different cortex, so each sense has a different part of the brain. Cross modal effects arise when direct connections are made between inputs and another cortex. For instance, sound might go to the visual cortex and change what you see, or vice versa. Usually people might consider food’s smell and taste (perhaps occasionally colour too) when thinking about what makes up the flavour of food but sound also plays a huge part our experience when eating food. The sound of the food in the mouth sends a signal to your brain and adjusts the way we perceive the texture. You can serve someone stale crisps and amplify the sound of the crunching of the crips through headphones, the person will not be able to tell that they are stale but will instead think think that they are fresh and crunchy.


Heston Blumenthal made a bittersweet toffee and got people to eat a piece while listening to the light tinkles of a piano’s upper octaves. He then got them to eat another piece while listening to the deeper rumbles of brass instruments. The people tasting it thought that he’d managed to make a toffee that matched the sound of the instruments: a sweet one for the light tinkling piano, and a bitter one for the deeper rumbles of the brass instruments. What was in fact happening was that the auditory signals generated from the instruments were targeting the diners attention to the sweetness or bitterness. So an appropriate sonic cue can be used to direct a persons attention to a particular flavour!



Kitchen Theory is an experimental kitchen, multi-sensory design studio in London. They marry gastronomy and psychophysics (the branch of psychology that deals with relations between physical stimuli and mental phenomena) to create gastrophycis. They run experiments like asking you to arrange four coloured spheres (white, black, green, red) of food to represent four (of five, the fifth being umami) tastes (sweet, sour, bitter, salty). The white is for salty, the black is bitter, green sour and red sweet.