Touch is the physical contact of the body with an object or element providing a response that triggers some reaction in the brain. This sense is local and does not allow the individual to receive or provide a tactile response over distance. There are several types of touch with different mechanisms to provide varying versions of the sense. As such, this section will be different than the other four classic senses, vision, hearing, taste, and smell. Most forms of touch are on the exterior of the body, especially the skin. However, our interiors also are able to sense touch in various forms, such as tension and pain.
We use touch to understand our spatial relation to the world, brushing against the surface of any object within the environment. Depending on the part of the body that is providing the tactile sense, there are different sensations that can be experienced, and through experience and innate understanding, we are able to differentiate the feelings and provide a response in reaction. Some forms of touch are pleasurable, but many are not, and the body must take any cues that are available to keep itself in a safe position. When used in relation to other senses, such as hearing or vision, we are able to use touch to understand the form and makeup of many or most objects, without requiring the dissection or definition of them. This intuition represents the powerful interplay of the sense of touch with the brain, where the body can provide sensory input, and the mind creates models or understanding.
Touch is likely our first sense in evolution. The receptors and the interaction with the brain can be said to be relatively simple in relation to the other senses, especially hearing and vision. We can argue touch is very close to taste, because the elements must come into contact with the body to ensure there is a reaction to the elements explored. Smell is similar in some ways because it uses a simple interaction with the environment to produce the sense response.
We must use touch when other senses are lacking, however the intimate connection that is provided with the sense, because of proximity makes it a sense that can act successfully alone or in combination with one or more of the other sensory modes. There may be a very immediate understanding of the world through the various forms of touch which are not possible with other senses, such as vision. This is because touch is immediate and present, whereas the other senses, besides taste, require some translation or definition of meaning in the brain for understanding. For one without experience with a new object, the nature and importance of the novel element is unknown, and it is necessary to learn what the object is at distance. We can argue this is the case with touch, however the interaction and instant sensing of the object in question make understanding extremely fast–as fast as the speed of electricity through the nervous system.
We use touch in times without other senses, but also in combination with other senses to have a complete experience of the object. This can take place at anytime and anywhere, and our bodies are constantly taking touch information that can be filtered out. Arguably, any form of touch can be turned off or hidden through the brain to avoid constant response to a persistent input. Some might say that pain is not avoidable. This could very well be true, and it is extremely important for the body to be protected and without danger. There are conditions that don’t allow a person to feel pain, and though this at first could be wonderful, in reality, it is very dangerous. To think that one can put an appendage into a flame or slice the skin with a knife, and the individual feels no pain, this is very scary and likely will not allow the person to stay healthy, as there are hazardous things everywhere in the world, and the body needs this sense of pain to avoid the dangerous things.
The sense above is nociception, the sense of pain, but there are many for touch. Some of the other senses of touch are: pressure, itch, cold thermoception, heat thermoception, proprioception, tension, stretch, vibration, equilibrioception (which some might lump with hearing), thirst, and hunger. Each of these has specific mechanics and a special response in the brain. We will look at each of these separately, but for now, we will look at these all as the general sense of touch.
As mentioned before, touch is very personal and must occur at the object or person. This is the same with taste, making them similar. In addition, taste has various types which tell the mind and body what is being consumed, and similarly, touch has many types that provide different pieces of information to the brain. The other senses, vision, hearing, and smell, use distance and can provide a sense of spatial relationships and size. Whereas, touch has a limited ability to experience magnitude of space, only able to measure with the count of sensors and movement across a surface. This can be useful when the other senses are limited, but it is not efficient and it requires the user to be in contact with the planes and edges of a space.
One might argue that many or most forms of touch are binary, only having an on and an off. However, with the introduction of multiple touch sensors and multiple types of touch sensors, we develop a sense magnitude as well as directionality. To do this, the touch sensors must be arranged in an array, and the sensors are wired together and coordinated at the brain to provide mapping of an environment. If there are limited touch sensors, the body must probe locations over time and rely on memory to produce a map of a space or object. The sense is so simple in many of its forms that the experience of sensing is only heightened through the lack of use. That is, if something is touched constantly, then there is no reaction and no meaning. However, if there is space or time between activating touch, the experience and meaning are heightened.
With this understanding of limiting the use of touch, it should be the designer’s goal to use the sense strategically and only on occasion. To use it constantly would overwhelm the user and lessen the experience. But, when should someone use the sense? Because it is more effective with limited use, it is best to use touch at specific moments when it is necessary to grab the user’s attention in conjunction with another sense, such as hearing or smell. You find people do this in daily conversation. Someone might touch another’s arm to add gravity or focus to spoken words. The added sense heightens the intensity of an interaction to throw someone into a new understanding or experience.
The worst time to use touch is when trying to show objectivity and to sway someone. Because the sense of touch is very intimate and up front, the use of the sense should be invited and desired by the user. Otherwise, the use of the sense might be inappropriate or even abusive. For things that should be removed from immediate experience, the use of the senses that can be used across space are better. These senses are vision, hearing, and smell, which all can provide experience but they are less invasive and do not intrude on personal space as we interact with the physical environment.
Touch can be a very useful solution for design, because it is used by everyone and the sense experience can vary over time or by the user to create everchanging interactions. Whereas, other senses such as taste and smell can be argued to be limited to a set number of feelings, given by the number of receptors. Even vision and hearing may not have many variations, especially vision. Hearing allows variation by tone, depending on the source. However, touch can have variation that is private and personal, in that the touch is local and is not shared unless another is at the source of the sense experience. The other senses, besides taste, are shared among the individuals in the space, so they can be said to be public. Touch and taste can be said to be private.
We can use touch in multiple ways. First, we have tactile objects and forms that we touch. However, there is also the opposite where the object or surface touches the user. This is a nice solution for dynamic design, where the touch experience is in movement and addresses the user. A third type of touch is where objects or entities touch one another. This is somewhat foreign, but it allows us to be empathetic and virtually experience the sensation. However, one might argue this is the use of vision. Finally, there is the individual touching another living entity. Again, this is a very personal experience and can only occur with the permission of both parties.
Touch is a useful sense for design, because it is pervasive and immediate. We can use it for any and every design, and it would not seem out of place. The hands and body allow us to transfer knowledge without communicating with writing. In addition, this transference can take place without the use of vision, which tends to be the sense we lean into most. As such, we can have sensory experience without looking, and we can have multiple inputs across the body to provide two or more meanings. However, it is usually better to provide a consistent message in a design, even with multiple inputs.
A change to make touch a central sense for design is the transformation of a space to allow repetitive or continuous interface with surfaces to allow the body to take the design intent. This would mean changing the dimensions and orientation of the spaces to provide a more constricted and folded space to ensure the body has access to surfaces as moments of experience. So, a great volume would not be best to provide a textural narrative, instead a space that is more like a corridor or well-furnished room will provide better opportunities to tell a story through touch. One of the best and most consistent surfaces for touch is the floor, which must always be traversed. The floor can have various materials and textures, but it must be clear for the designer what and when to use these textures, otherwise the meaning could be lost.
To improve the use of touch in design, we should have a thesis for our design. Then, the senses should be tools that are used specifically and aptly to tell the desired story. This would probably mean that we should be sparing in the sensory inputs to limit experiential overload, in most instances. With fewer experiences, it is easier to control the story, and the more sense inputs we add, the closer we should watch the meaning and definition of the sense.
If we were to only use touch, we should have a base state, and then have a clear intent with the material or texture added for variation. What are the meanings of various materials and textures? Are soft things happy and comfortable? Are hard and sharp things mean and standoffish? Are these understandings of materials common across cultures? Some surely are, as we experience these forms of touch with the body, and the body attempts to find a state of comfort and safety continuously. A rigid and ridged object will likely provide some form of excitement and not lull the user into sleep. However, surely there are variations in meanings of materials from person to person and culture to culture. Some might find the warm and fuzzy experience of flannel as comforting, while others might find it hot and overwhelming. In addition, the way the sense is experienced may agitate some but soothe others. For example, running your bare feet across a swath of carpet could be satisfying for you, but bother another, like fingernails on a blackboard.
It is hard to have a design that does not incorporate touch through at least the feet and floor. However, touch is not required for design, even though it tends to be present at least in the materiality of the design output. In this way, the designer should acknowledge the presence of the sense of touch, and provide a clear use of the sense in at least the places where the human body comes into contact with the design installation. With this, we can look at various uses of touch. Touch can be used to provide a visceral reaction, convey information, complement meaning from another sense, and counter another sense.
To use touch, we require our body, and with the body in a space, we have presence. Therefore, touch requires and exploits presence. We cannot have a haptic or textural landscape at distance, so this can attract and ingratiate people to and in a space, especially in a world that relies so much on the digital and virtual. A website or social media surface cannot provide touch, and the designer can capitalize on this to bring people to a space or place that provides the sense. In contrast, we can remove the sense of touch to deprive and direct through the use of pauses in stimulation–a cold, hard space is not likely to make people linger. Furthermore, the hint of the lack of experience can push individuals to move to another space in a sensory form of propaganda, the bandwagon or the fear of missing out.