The Perception-Action through Affordance: Ingenuity or Illusion? Is Intuitive Interaction Truly Possible?
Affordances — a key concept in cognitive psychology — reveal how we perceive possibilities for interaction with our environment. Exploring how perception influences our actions and daily choices allows for a better understanding of human behaviours and attitudes. This knowledge provides an essential foundation for improving user experience in design fields (e.g., interface design, presentations, collaborative technical documents, dashboards).
In this article, we aim to define the concept of affordances, explore how they are utilised in interface design, and demystify the myth of intuitive interaction.
I. Definition
Cognitive psychology unveils the fascinating ability of the human brain to translate sensory signals (sight, hearing, balance, etc.) into rapid and adaptive actions.
For instance, when someone throws an apple to you, the electrical signal sent to the brain’s movement-related area allows you to act instantly — catching the apple mid-air (see our article on visual perception for more details). Similarly, the visual perception of a steaming cup of tea, combined with your knowledge and experiences, intuitively guides you toward the appropriate action: not grabbing the cup by the body but by the handle. This phenomenon, where the object itself induces an action, is known as an affordance.
Affordance is defined as the ability of an object/system to evoke its use/function. Affordance triggers spontaneous interaction between an environment and its user (Gibson, 1950, 1977). Leveraging affordances makes the use of an object or service intuitive.
Who hasn’t pushed a door when it should be pulled, and vice versa? In the first example above (Figure 1), we refer to an affordant door because the absence of a handle on one side induces the action of pushing, while the handle on the other side induces the action of pulling. Affordance here helps minimise errors, optimising the user experience.
In the second example above (Figure 2), the 3D crosswalk can be deemed more affordant than a traditional 2D crosswalk. Implemented in Iceland, it significantly reduced motorists’ speed. This method achieved the desired behaviour — slowing down — without physically altering or elevating the roadway.
II. Affordances in Interface Design
A. Designers’ Ingenuity?
Affordances are ubiquitous in our digital interfaces. They must capture the user’s attention and suggest the function of the element in question. All user senses (sound, sight, touch, etc.) can be engaged.
Here are some examples of devices promoting affordance and thus encouraging action:
- Objects like buttons and hyperlinks (also known as ‘call-to-action’)
- Textual/linguistic messages focused on the action to be taken, such as ‘send’, ‘reply’, ‘cancel’, ‘validate’
- Graphic elements: menus, arrows, magnifying glasses, etc.
- Metaphorical icons: envelope, phone, etc.
Clickable buttons (or ‘call-to-action’) in an interface are a good example of affordant digital objects. By playing with size, contrasts, textures, the object suggests its own use.
Thus, perception goes beyond mere visual recognition and includes proactive interaction, illustrating how affordances guide our behaviours in the digital world.
However, it is crucial to delve deeper into understanding affordances, particularly their roots in human experience and the underlying mental models.
B. Collective Illusion: Demystifying the Myth of Magical Intuitive Interaction
In reality, an object does not solely suggest its own use. Affordances are not a magical concept solely tied to object design. An individual’s knowledge and experiences with an object are prerequisites for affordance.
For instance, when a user encounters an icon consisting of three horizontal lines, interpreting this icon as a means to open a list of clickable links depends on the individual’s past experience. In other words, the ability to recognise this icon as a navigation menu and be prompted to act — pressing the icon — only exists if the individual has prior knowledge or experiences related to this icon.
In essence, affordances exist only through our mental models, knowledge/experiences (e.g., Creem-Regehr, Gill, Pointon, Bodenheimer & Stefanucci, 2019). Consider affordances as a method, a design tool based on our understanding of human functioning. For example, a staircase becomes affordant only when I am aware or knowledgeable — usually by learning to walk — that it consists of steps, and typically, each of these steps requires a forward step. Indeed, various studies have shown that a staircase is not affordant for children until a certain age, usually when walking is mastered (e.g., Warren, 1984).
In summary, an object does not suggest its use on its own; it requires the human brain to exist.
Bibliographic References
- Creem-Regehr, S. H., Gill, D., Pointon, G., Bodenheimer, B., & Stefanucci, J. K. (2019). Mind the gap: gap affordance judgments of children, teens, and adults in an immersive virtual environment. Frontiers in Robotics and AI, 6.
- Gibson, J. J. (1950). The Perception of the Visual World. Houghton Mifflin.
- Gibson, J. J. (1977). The Theory of Affordances. In R. Shaw & J. Bransford (Eds.), Perceiving, Acting, and Knowing: Toward an Ecological Psychology. Lawrence Erlbaum Associates.
- Gibson, J. J. (2014). The Ecological Approach to Visual Perception. Psychology Press. ISBN: 978–1848726153.
- Warren, W. H. (1984). Perceiving affordances: visual guidance of stair climbing. Journal of Experimental Psychology: Human Perception and Performance, 10, 683–703. doi: 10.1037/0096–1523.10.5.683.
