Mental Model Literature Review - Part 1

In this post I not only wish to contextually review the literature on mental models but also to define the use of the term that will be central to my first practical PhD project. Mental Models is unfortunately a term that has had its meaning diluted by non-cognitive science practioners such as Indi Young (more on this later). Therefore I will be exploring Mental Models firstly from a cognitive science perspective in order then to draw parallels and influences into Interaction Design. This post is not a defined thesis on my part but an attempt to draw together the essence of mental models. There will be theoretical holes in what I will post, so feel free to point them out. Look on what follows as simply my first attempt to stitch together my understanding of a very complex cognitive science discourse, from a discipline that is not my own. I will continue this literature review across several posts with the aim of refining my understanding.

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To begin with I am going to quote psychologist Kenneth Craik (1914-1945) from his 1943 book The Nature of Explanation. Craik is cited by cognitive scientist Johnson-Laird in his 1983 seminal work Mental Models as proposing the first modern hypothesis on humans being processors of information in order to understand phenomena.

”If the organism carries a “small-scale model” of external reality and of its own possible actions within its head, it is able to try out various alternatives, conclude which is the best of them, react to future situations before they arise, utilise knowledge of past events in dealing with present and future, and in every way to react in a much fuller, safer, and more competent manner to emergencies which face it.” (Craik, 1943, p57)

This statement was to open up a whole new area of research within the already new scientific discipline of cognitive science. By 1983 Mental Models research had two seminal works that explored this concept. Johnson-Laird proposed that the human mind uses propositional reasoning instead of reductive mathematical logic to understand phenomena. Gentner and Stevens, in their edited collection of papers, also entitled Mental Models, present a diverse range of views, including an early paper by Dr Donald Norman who here begins the discourse upon the Design Model. If Johnson-Laird proposes propositional reasoning, then Gentner and Stevens' book explores the structure of knowledge representations specific to different domains of application. Johnson-Laird states in introducing his book,

"The psychological core of understanding, I shall assume, consists in your having a 'working model' of the phenomenon in your mind. (…) you have a mental representation that serves as a model of an entity (…) A model has, in Craik’s phrase, a similar ‘relation-structure’ to the process it models, and hence it can be useful explanatorily; a simulation merely mimics the phenomenon without relying on a similar underlying relation-structure. Many of the models in people’s minds are little more than high-grade simulations, but they are none the less useful provided that the picture is accurate; all representations of physical phenomena necessarily contain an element of simulation." (Johnson-Laird, 1983, p2/4)

The importance here is that a 'relation-structure' the functionality of a cognitive conceptual model. To propose an explanation on how a phenomenom works, a model that is constructed by a person is NOT improved by them also trying to understand the specific context it is encountered in. The specific context is not transferable to another context but the mental model will be. The model will not be complete each time it is applied, but in Chomsky's term 'explanatory adequate'. To Johnson-Laird because a mental model is constructed by mental logic, mental logic has six main problems. Inference, formulation and deduction all are contributory to the empirical nature of mental logic. He lists the problems as (pp39-40):

1. People make fallacious inferences.


2. Which logic, or logics, are to be found in the mind?


3. How is logic formulated in the mind?


4. How does a system of logic arise in the mind?


5. What evidence there is about the psychology of reasoning suggests that deductions are not immune to the content of the premises.


6. People follow extra-logical heuristics when they make spontaneous inferences.

People's powers of deriving a reasoned solution based upon a premise they have, or from precedence is strongly affected by their own cognition that is deceptive. Mental models, although helpful to understanding a phenomenon, are inherently 'incomplete' (Johnson-Laird, 1983)(Norman, 1983), 'doubtful validity' (Norman, 1983), 'fragmentary' (Norman, 1998), 'dynamically constructed' (Preece et al, 1995), and 'not always correct' (Gentner and Gentner, 1983). As Johnson-Laird argues, the formulation of a mental model to understand a phenomenon is 'propositional reasoning' on behalf of each individual. Norman explains this in more accessible terms:

"The power of mental models is that they let you figure out what would happen in novel situations. Or, if you are actually doing the task and there is a problem, they let you figure out what is happening. If the model is wrong you will be wrong too." (Norman, 1998, p71)

If the person's proposition regarding the causality, relationships and mechanisms within a phenomenon encountered is poorly appreciated then their understanding of that phenomenon will not work. But an incomplete proposition that does capture the behaviour of that phenomenon, that for them represents the causality and mechanisms of that phenomenon based upon previous experiences, or from fragmentary experiences of aspects of similar phenomena, can arrive at an 'explanatory adequate' mental model. This is why Norman describes the human mental process as "unscientific" that supports Johnson-Laird's argument that humans do not use reductive mathematical logic as the brain is a computer. In their book The Embodied Mind Varelo et al refer to phenomenologist Edmund Husserl (1859-1938) to contextualise human cognition from a different perspective, where a human's 'sensorimotor capacities' is enabling enough to successfully interact within an environment with the phenomenon. According to their thesis Husserl claimed

"that to understand cognition, we cannot take the world naively but must see it instead as having the mark of our own structure. He also took the second step, at least partially, in realizing that that structure (the first step) was something that he was cognizing with his own mind.(…)He explicitly focused on the experience of consciousness in what he called the “lived-world.” The lived world is not the naive, theoretical conception of the world found in the natural attitude. It is, rather, the everyday social world, in which theory is always directed toward some practical end. Husserl argued that all reflection, all theoretical activity, including science, presupposes the life-world as a background. The task of the phenomenologist now became the analysis of the essential relation between consciousness, experience, and this life-world.” (Varelo et al, 1996, pp16-17)

For each person to construct a mental model of a phenomenon based upon proposition reasoning, entails them cognizing the problem from their previous experiences built into a appropriate functional model (Preece et al, 1995) developed from existing knowledge of a similar context. As a mental model is a dynamic conceptual tool to solve a problem within a phenomena, they can be be said to be drawn from Husserl's concept of the 'lived-world'.

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References

See Design Model - statement for list of references cited in this post.

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1st Practical PhD Project… thoughts

On my project blog PhD Project 01 I am still documenting research upon the cognitive psychology of users' mental models which will take me into April as I need to source a couple of key texts I couldn't get from ECA's or University of Edinburgh's libraries. That said one key text yesterday, firmly situated within cognitive science literature, has suggested a structure for my practical research project. I will expand upon this again over the coming months in more detail.

The idea so far in its embryonic state is this…

Phase

1. Qualitative Experiment on up to 36 subjects to undergo an initial online survey to identify a capacity to describe and communicate a cognitive model (subject to be defined). The subjects who can clearly communicate their 'mental model' will be graded into study groups for the next phase.
   
2. This study group will then be asked to explain how they understand how they perform an interactive task.
   
3. These 'mental models' will be visually documented.
   
4. From this documentation visual interactive prototypes will be produced as iterative tests of a 'designer's model'.
   

I do realise that this is very woolly right now and lacks definition. It's root is in an experiment performed by Dedre Gentner and Donald R. Gentner disseminated in their 1983 paper "Flowing Waters or Teeming Crowds: Mental Models of Electricity". My outcome will be demonstrably different to theirs, but their method is certainly a foundation to develop on. I will continue to work on this planning over April.

To summarize though what my intended outcome will focus upon: it will be creating a range of interaction prototypes that are define and designed using 'designer models' interpreting users' 'mental models' of the interaction. The outcome will be focused on visually communicating the experimentations of matching an interface design to how a user thinks it works rather than how it works.

I know I can communicate this better, so please bear with me as I begin to form my methodology and outcomes. Any comments would be greatly received, but please add them to this post by clicking 'Comments' rather than emailing them. Once I have the project more defined I will utilise the Interaction Design community www.ixda.org to inform me of any similar experiments, to ensure I am doing and experiment that will open new ground.

The final thing I need to emphasize is that this project will focus on the visual communication of the interactive process.

Reference:

Gentner, D. & Gentner D.R. (1983) Flowing Waters or Teeming Crowds: Mental Models of Electricity. In D. GENTNER, and A.L. STEVENS, eds. Mental Models. Lawrence Erlbaum Associates Inc. pp99-129

All in the mind?

As I'm not a psychologist I am well out of my comfort zone with this next attempt to understand interactivity but is interactivity dependent upon perception? I am an avid listener of Melvyn Bragg's Radio 4 programme In Our Time. One programme deals with perception and Bragg introduces the programme by saying "Perception is a tangled web of processes and so much of what we see, hear and touch is determined by our own expectations that it raises the question of whether we ever truly perceive what others do." Certainly within interactive design perception is crucial but is there an inherent problem when we attempt to make an interface intuitive that we cannot solve?

If we attempt to put into place enough visual cues and spend time perfecting the interactive loop (see image, adapted from a diagram by Bill Verplank of Stanford University) in order to make the interface usable for as many people as possible, are we still being kneecapped by a philosophical bullet. That is do we assume the user (insert your preferred nomenclature here) perceives the interface in the way we expect? Not exactly an earth-shatteringly original concern but when we consider that interactivity is more than just hand and eye, but also factors such as asynchronous and real-time communication, interchangeability of roles, modification of content within real-time etc. and tangibility affect the way that the perceived interactivity works.



It is therefore a little disconcerting for me to think that even taking into account semiology, typography and the psychology behind colour theory I may still need to consider deeper philosophical issues such as suggested by Spiro Kiousis in his 2002 paper "Interactivity: a concept explication". Kiousis proposes that interactivity, on an operational basis "is established by three factors: technological structure of the media used (e.g. speed, range, timing flexibility, and sensory complexity), characteristics of communication settings (e.g. third-order dependency and social presence), and individuals’ perceptions (e.g. proximity, perceived speed, sensory activation, and telepresence)." We already are aware that each individual has different ability in reading on screen and hand-eye coordination with input devices, but is there deeper issues we need to be aware of.

I am re-reading Kiousis' paper and will post again my own observations.

References

Kiousis, Spiro (2002) Interactivity: a concept explication New Media & Society, SAGE Publications, Vol4(3):355–383, Pp 379

Self-evident interfaces and perceivable possibilities

In attempting to understand Durrell Bishop's research into self-evident design with more clarity I thank Fusewire and Alec for their comments to my previous post. Cultural mediation and perception appear to be two aspects that need considering with Bishop's thesis. With further reading around the subject I have read highlights of an interview with Bill Gaber, professor of design at Goldsmiths College in London. In this interview he cited the work of perception theorist J.J. Gibson, in particular Gibson's 1979 book on The Ecological Approach to Visual Perception.

As I have an interest in human evolution and the development of human creativity (in the words of Douglas Adams "the secret is to keep banging the rocks together guys!") Gaber's thesis was understandably of interest. If, as Gaber hypothesizes, our evolution has allowed our species to benefit from perceiving what actions would be useful to our survival over those that wont, we are able to perceive, validate and combine complicated actions together such as our ancestors' stone tool-making. This outcome of perceiving the possibilities when flint is struck with another stone, mammoth meat can then be butchered for the tribe back home is disseminated through perceptual experimentation and then cultural-mediation. Each stone age tribe makes stone tools with their own twist on the technology, evolving it through an ongoing iterative process of constant development. This perceptual process is the same as we use to evolve interactive design.

Gaber in his research and work when at Xerox EuroPARC has tried to demonstrate that people can deal with graphical elements within interface designs as if they are self-evident physical objects by "thinking about the interface being a physical environment rather than being a kind of command-line-driven conversational metaphor". This is more than just creating an icon of something from the physical world and placing it into the visual design of an interface. A rewind button on a tape deck does not function in the same way as a backwards button on a physical or digital CD player. A scrub wheel does not function in exactly the same way on an iPod as it does on an analogue device. The physical function may be similar but the perceived outcome may not match the outcome. Gibson's theory refers to these perceivable possibilities for action as "affordances" and Gaber has applied Gibson's affordance theory to interactive design by attempting to peel back "the notion of affordances to its real essentials".

Has anyone read Gibson's work? I would be interested to hear if his theory has been advanced further or has been dismissed in favour of a more robust thesis. Any further reading on this matter would be greatly appreciated by myself.