Affordances and Related Concepts Flashcards
(25 cards)
Who do these concepts belong to?
Ecological approach, Affordances, Real-world Action possibilities, Perception for action
James J.Gibson
Who do these concepts belong to?
Real affordances, Natural signals, perceived affordances, and symbolic communication
Don Norman
Who do these concepts belong to?
Perceptible Affordances, Hidden Affordances, False Affordances, and Sequential and Nested Affordances
Bill Gaver
Who do these concepts belong to?
Physical Affordance, Cognitive Affordance, Sensory Affordance, and Functional Affordance
Rex Hartson
Who are the four most important contributors to the evolution of affordances?
- James J. Gibson
- Don Norman
- Bill Gaver
- Rex Hartson
Who is James J. Gibson
Gibson developed the term ‘affordance’, which he used for the first time in The Ecological Approach to Visual Perception’ in 1979.
Ecological Approach
- Gibson emphasised the link between perception and action, which is central to the ecological approach to visual perception. “In this account, affordances are the fundamental objects of perception” (Gaver, 1991). According to the ecological view, our perception of the world is influenced greatly by our aims and objectives. We are constantly interpreting and translating perceptual information to help us determine what we can do with things in our environment. Therefore, the ecological approach is interested in how perceptual information helps us interact with the world to maintain physical and mental well-being.
Affordance
Gibson introduced the term ‘affordance’ before human-computer interaction was the vast and rich subject we currently study. He used the term to capture the relationship between people and things in their environment, and how each person’s intentions, capabilities, strengths, and weaknesses, affect their ability to identify and take advantage of an object’s actionable properties.
Real-world Action Possibilities
Gibson referred to affordances as action possibilities. Objects in the real-world possess physical properties that enable us to determine their action possibilities. For example, a cup has a hollow which allows us to determine its affordance of storing fluids. According to Gibson, humans are primarily interested in these action possibilities, and perception is biased to identify these affordances over any other characteristic or set of characteristics associated with an object.
Perception for Action
A concept central to Gibson’s view of visual perception, which refers to the human drive to perceive the world as a series of objects that afford certain activities or possible uses.
Don Norman
Author of The Design of Everyday Things (DOET), in which Norman introduced a number of concepts to human-computer interaction, one of which being affordances. Norman has played a significant part in both bringing the term to the design community and advancing our understanding of how we can use the concept of affordance to assess and evaluate designs.
Real Affordance
Norman distinguished between real and perceived affordances; using the former when referring to the actual properties of things.
Natural Signals
These are the perceptible cues naturally possessed by an object or thing which enables an actor to determine one or more affordance. Natural signals arise from the actionable properties of things in our environment. For example, the shape of a handle signals to the user what it can be used for and how it can be used. The concept of natural signals was introduced by Norman in DOET.
Perceived Affordance
Perhaps, the most contentious concept from DOET, Norman used the term perceived affordance to distinguish between the actual or intended action possibilities, and the action possibilities users perceive as afforded on the basis of perceptual information.
Symbolic Communication
Designers use a number of different methods of communicating the action possibilities afforded within their products. Don Norman referred to these methods as symbolic communication. Examples include icons, text, and cultural conventions.
Bill Gaver
Three years after Don Norman released DOET, Bill Gaver attempted to evolve the concept of affordance in Technology Affordances. Within Gaver’s compelling account he distinguished between three types of affordance: perceptible, hidden, and false affordances. He also emphasised the role of perceptual information in human-computer interaction; taking inspiration from the ecological approach adopted and championed by James J. Gibson.
Perceptible Affordance
Any affordance we are able to determine on the basis of perceptual information is referred to as a perceptible affordance.
Hidden Affordance
Any affordance where an action possibility is available, but not revealed by perceptual information is referred to as a hidden affordance.
False Affordance
When perceptual information suggests the availability of a non-existent affordance.
Sequential and Nested Affordances
Gaver introduced the concepts of sequential and nested affordances. Sequential affordances refers to any situation where acting on one perceptible affordance leads to the availability of another, or multiple, new affordances. Nested affordances are affordances grouped in space, in that certain action possibilities are placed in close proximity to help users carry out related activities with greater speed.
Rex Hartson
Of the four accounts covered in this summary, Hartson provided the most recent distinction between types of affordance. Hartson built on the work of Don Norman in an attempt to demystify the affordance-based terminology used in interaction design (IxD), as Norman’s concept of affordance had been somewhat misused in the years following the release of DOET. Hartson distinguished between physical, cognitive, sensory, and functional affordance, and he also emphasised the inextricable link between these different types of affordance.
Physical Affordance
Similar to Norman’s concept of real affordances when referring to real-world objects, but unlike Norman, Hartson uses the term in IxD when referring to the basic action possibilities in screen-based user interfaces, such as clicking on icons and other meaningful parts of the display.
Cognitive Affordance
imilar to Norman’s concept of perceived affordance, a cognitive affordance is any design feature which helps users with their cognitive activities, encompassing thinking, learning, problem-solving and decision-making.
Sensory Affordance
This concept refers to the provision of sensory information, which helps the user determine the existence of affordances. Without sensory information the user is usually unable to determine an object’s action possibilities, and this affordance represents the first stage of most instances of human-computer interaction as the user must first perceive what is available (i.e. detect the sensory information), before they can do anything else.
