Take a Load Off: Cognitive
Considerations for Game Design
C hris Lawrence
School of Design, Communication & IT
University of Newcastle
Callaghan, NSW, Australia 2308
[email protected]
ABSTRACT
As the quest for designing and developing exciting and
engaging computer games continues, one must cast a thought
towards what it is that makes such entertainment engaging, or
indeed, disengaging. One might be of the mind that an
interesting and captivating computer game would be one that
evoked a high level of thought activity and concentration. On
the other hand, it could be argued that if the player of a game i s
bombarded with instructions, information, tasks and
decisions, the result is a confusing, stressful and generally
unpleasant experience. To avoid giving our gaming audiences
mind indigestion, some sort of strategy must be employed t o
facilitate an acceptable supply of cognitive stimulation. This
article uses cognitive load theory to explore and discuss a
number of considerations and possible tactics in presenting
and organising complexity in a computer game.
General Terms
Design, Human Factors, Theory.
Keywords
Cognition, cognitive load theory, computer games, graphics,
design, interface.
1. INTRODUCTION
1.1 Metacognitive Priorities
For many years, the disciplines of education, psychology and
instructional design have sought to understand the
capabilities and limitations of the human brain in an effort t o
develop new strategies that would streamline, amplify or
stimulate the learning process. Likewise, industries concerned
with visual communication, marketing and entertainment have
been making efforts to learn how consumers and audiences
think with the aim of finding more effective and efficient ways
of building awareness, gaining attention and altering
perceptions. In the case of knowledge acquisition in an
educational or learning context, a strong emphasis is placed
on the need for a deeper level of thinking or metacognition.
Although the ability to evoke a concentrated level of thought
might be a desirable quality for material produced for the
purposes of advertising or entertainment, it is not rated as an
essential ingredient. More common approaches for promoting
information familiarity tend to lean on that of conditioning,
repetition and association instead. It could also be said that
the elements of entertainment and aesthetic pleasure are often
desirable for educational and instructional material but not
necessarily of high priority - whereas for graphic design and
entertainment it is arguably critical.
In discerning the different primary objectives that these two
areas have in communicating their respective messages, i t
would seem beneficial to explore how the research conducted
by one discipline could be applied to the other. In this paper,
it is suggested that even though education holds
metacognition as a much greater priority when communicating
information than the disciplines of entertainment and visual
communication do, established cognitive theories present a
new way of understanding the way entertainment and visual
communication operates. Specifically, this paper discusses
how cognitive load theory has the potential to be adopted i n
the design of computer games and interfaces.
2. COGNITIVE LOAD THEORY
2.1 Definitions and Established Components
The subject of cognitive load theory has a number of active
contributors presenting a variety of categories, perspectives
and conclusions [12]. On an elementary level, the issue that
would seem to put all of this research under the one umbrella
is that enquiry is based on the core notion that the human
brain has a limited capacity to process information. In
understanding those limitations it is commonly suggested
that certain measures can be developed and employed t o
utilise cognitive capacity in a more optimal fashion. However,
as a closer examination of cognitive load theory literature will
reveal, a generally accepted underlying architecture exists as
well as a number of observed effects and overload scenarios.
As argued by Sweller et al. [12, 14, 15, 18], human cognitive
architecture possesses two main types of memory - working
memory and long-term memory. Working memory is primarily
responsible for the selective processing of information
gathered by our senses (such as auditory and visual) and has a
very limited capacity and duration. We use our working
memory to make sense of the information we receive,
organising and constructing more complex concepts into what
are referred to as schemas. Schemas are stored in and retrieved
from our long-term memory, which unlike working memory,
has a comparatively unlimited capacity. Schemas retrieved
from long-term memory give us the ability to automate our
learning and understanding without consuming the same
amount of working memory that was expended in the creation
of those schemas. The varying levels of automation that each
schema provides, allows us to learn increasingly difficult and
complex material.
Several categories of cognitive load have also been
established; intrinsic cognitive load, extraneous cognitive
load and germane cognitive load [12]. Intrinsic cognitive load
describes the situation whereby a concept or piece of
information is by its very nature difficult to understand as all
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the elements within it interact, and without such interaction,
meaning is lost. When the development of schemas in working
memory is disrupted by other incidental or irrelevant
information, it is referred to as extraneous cognitive load.
Germane cognitive load on the other hand, is additional
cognitive load for the purpose of enhancing schema
acquisition rather than interfering with it.
Because extraneous cognitive load is undesirable in a learning
context and is a comparatively easier problem to deal with
than intrinsic cognitive load, quite a number of different
strategies have been developed to reduce it and have given
place to a number of observable effects. Sweller et al. [16]
identified the split-attention effect as the situation whereby a
statement and a diagram must be integrated using working
memory in order to understand an instruction that neither the
textual or pictorial components could convey independently.
Split-attention occurs because there are two separate sources of
information that can only be examined one at a time. While
reading the text, one is unable to look at the diagram, and vice
versa. The modality effect describes the utilisation of both
audio and visual sensory input channels, thus effectively
expanding the capacity of a working memory that is only
really utilising one of the two channels. The typical example
given is that of the textual component of a split-attention
effect being transmitted as a spoken narration instead, freeing
the visual sensory channel to focus solely on the graphical
component.
2.2 Relevance to Game Design
For the most part, cognitive load theory has resided in the
context of learning and instructional design, but has
progressively broadened in disciplinary applications in recent
years. Although very little published evidence exists for its
use in the design of interactive entertainment, its usefulness i n
such a circumstance would seem obvious. The effective
learning of a computer game’s controls, interface, plot, rules
and general play should logically have a direct effect on how
successfully a player can operate the game. One could assume
that performing tasks such as prioritising game objectives,
problem solving, navigating a virtual space or simply
recognising the consequences of decisions and actions are
beyond a player who has not gained a basic understanding of
at least some of the aforementioned governing qualities of the
game first. It would also seem unlikely that a person would
persist in attempting to play a game that they are unable t o
understand or find any satisfaction playing - despite the
strangely contrary evidence that can be found in the game of
golf.
accentuating key words in the audible narration, adding
coloured arrows to indicate important images, and grouping
the text and images under meaningful headings and sections.
This signalling facilitated a more appropriate and concentrated
process of selecting and structuring relevant information for
the viewer.
Focal points, visual priority and hierarchy have arguably been
some of the most heavily utilised principles and techniques i n
the graphic design industry since it began. Bringing attention
to the most vital information in a piece of visual
communication first is almost always a primary consideration,
particularly in a society heavily saturated in advertising,
marketing and media all competing for consumer attention.
The study of effectively directing a viewer’s attention to a
particular section of text or imagery is also known as
highlighting [8] and has been explored on an empirical level
by Williams [19] and Maguire [9]. Williams looked closely at
textual highlighting which included attributes such as bold,
italic, underlined, inversing, blinking, movement, colour-shift
and typeface changes concluding that highlights such as allcaps and underlining were to be avoided in favour of a limited
use of bold, italics and point-size increases.
3.2 A Possible Implementation
Suppose we take the common example of a computer game that
uses a cartographic visual to assist in explaining the
objectives of a battle-plan that must be followed (Figure 1). In
amongst the instructions for the game, a number of locations
on the map are mentioned such as the starting point, a
township from which to collect supplies, a number of
fortresses that must be conquered, and a finishing point.
Without the aid of signalling or highlighting, a split-attention
effect is present, as working memory is required to integrate
both the words and the picture in order to comprehend the
instructions properly. A portion of working memory i s
diverted to searching for the map locations featured in the
instructions, resulting in extraneous cognitive load.
3. CUES AND HIGHLIGHTING
3.1 Supporting Theories
In the context of multimedia learning, Mayer and Moreno [10]
describe a number of scenarios involving extraneous
cognitive load, and test a number of load-reducing methods.
One particular scenario describes a learning situation in which
a narrated animation included an excessive amount of
interesting, but ultimately digressive material. One method
successfully employed to reduce cognitive load in this
instance was referred to as a signalling effect and involved the
implementation of various audio and visual cues, directing the
viewer’s focus to the most critical information throughout the
presentation. Some of the signalling methods used included
Figure 1. Example of a computer game using a battle-plan
map without cues or highlighting.
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4.2 A Possible Implementation
To take the example of the battle-plan map once more, a
cognitive load issue still resides in the interface design if the
textual instructions are still being presented in a visual
format. Even with a number of visual cues and signalling
techniques employed, a split-attention effect remains, as the
player must still divide their attention between reading the
text and examining the diagram.
Figure 2. Implementation of basic visual cues
Implementing our understanding of the modality effect, one of
the obvious changes to be made in this circumstance would be
to generate a spoken narrative from the textual list of
instructions, which would then be broadcast and synchronised
with the visual cues and signalling. In order to avoid the
redundancy effect, the next modification would be to remove
the written instructions, which would not only deal with the
unnecessary duplication of information, but would release
more screen and layout space for the display of visual
components (Figure 3).
By adding simple visual cues at appropriate intervals of the
instructions, such as location names on the map becoming
bold when mentioned, a moving, coloured trail of arrows
indicating direction and location sequence plus small
animations representing the events that will occur at each
location, extraneous cognitive load should effectively be
reduced, resulting in a better chance of the instructions being
understood and followed (Figure 2).
4. AUDIBLE NARRATION AND PROMPTS
4.1 Supporting Theories
Paivio et al. [13] is commonly credited with establishing the
picture-superiority effect which essentially states that
pictures are easier to recall than words. However, Paivio et al.
and a number of others [1, 13] have also produced evidence
indicating that the combination of pictures and words together
are better remembered than either pictures or words alone.
“Words” can take on a number of manifestations though –
written as visible text or spoken in an audible voice.
As mentioned earlier, the modality effect in cognitive load
theory suggests that a learner that receives verbal and
graphical instructions in both audible and visual format
simultaneously will generally learn more efficiently than if the
same instructions were received in an all-visual format. Quite a
number of experiments have been conducted over recent years
[4, 11, 17] yielding a convincing body of findings supporting
the modality effect, many of which stress its importance in a
multimedia-training environment. Upon analysing a similar
scenario, Mayer & Moreno [10] described the method of
moving some of the essential processing from the visual
channel to the auditory channel as off-loading. Another
important conclusion drawn by Mayer & Moreno, and
supported by the work of Leahy et al. [7], is that there i s
credibility in what is referred to as the redundancy effect. This
effect is a reference to the cognitive load induced by the
presence of non-essential or unnecessary information –
particularly content duplication. It was noted that in the case
of having an audible narration accompanied by a visual text of
identical content, learners were reported as not performing as
well as when an auditory narration was the only word-based
transmission present.
Figure 3. Removal of redundant information
5. PROGRESSIVE DISCLOSURE AND
USER EXPERIENCE
5.1 Supporting Theories
In the late 1990s, a number of cognitive load theorists began
concentrating on an observable phenomenon now known as
the expertise reversal effect [3], whereby some of the methods
developed to reduce cognitive load, appeared to have a lesser
effect, and eventually an adverse effect, on learners who were
considered to have obtained a high level of familiarity or
experience with the general subject matter being presented. In
a typical example of a split-attention effect, Kalyuga et al. [6]
demonstrated that the text components of an instructional
presentation eventually became redundant material for a
learner with a high level of expertise, making a presentation of
the same material without the text a preferable alternative. This
would seem to support established cognitive architecture i n
that with every schema learned and developed, an appropriate
ability to automate learning is also gained. So, as a novice
develops into an expert, less cognitive effort is required t o
understand new material, therefore less information and
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instruction is required in order to lead them to that level of
understanding. The accommodations made in instructional
designs for this progressive reduction in instructor control
and increase in learner control has earned the description of
being a fading technique.
A technique that would seem to parallel that of fading i s
progressive disclosure which was a recognised presentation
tactic from early complex digital interfaces [5]. Another
method for preventing an overload of information, progressive
disclosure involves revealing only immediately relevant or
requested sections of information at a time. A common
example of this technique can be seen in drop-down menus or
advanced search interfaces within software and website
designs. Such a structure means that the more infrequently
used or less relevant sections of information remain concealed
until needed or appropriate. Although this is not a technique
necessarily designed to facilitate germane cognitive load (like
fading is), it does offer a method of reducing extraneous
cognitive load while offering flexible control over the level of
a system’s complexity (or at least perceived complexity). On a
multi-disciplinary front, the law of parsimony, or Occam’s
Razor [2] would similarly support the reduction of
unnecessary elements in a design or system to achieve
maximum simplicity so long as its functionality was not
drastically compromised.
In an entertainment context, progressive disclosure can also be
used as a method of enticing a person to explore a system. One
very simple example would be that of a season of thrilling
television episodes, where each episode progressively
discloses interesting information about the characters and the
underlying plot without giving away the entire story in all of
its complicated glory. Similarly, many theme park rides have a
built environment for the line-up that not only obscures the
length of the queue from would-be riders, but progressively
discloses sensory stimulus about the ride while they wait, for
example, video footage, sound effects and ride attendants i n
character.
5.2 A Possible Implementation
Let us assume that our hypothetical battle-themed computer
game has a very detailed level of control over how an army or
group of battle units behave. Techniques and strategies such
as attack formations, defensive and aggressive modes, patrol
routes and a number of other functions all require a control of
some sort in the game’s design. To display a button on screen
for each of these controls is likely to cause a little confusion
and disorientation for a player who is unfamiliar with this
style of game let alone this game in particular.
In light of fading and progressive disclosure techniques, a way
of catering to the novice user of the game would be to have any
of the less-critical controls that could otherwise be automated,
remain hidden or grouped under a small number of generic
controls. As the difficulty of the game increases with every
level or scenario, the deeper-level controls could be made
active. Alternatively, the player of the game could be given the
ability to toggle between the complete set of controls and the
simplified set of controls depending on their familiarity with
the game (Figure 4).
Figure 4. Example of progressive disclosure used in a set of
game controls
6. CONCLUSION
From the research that has been conducted within cognitive
load theory and the other related areas discussed in this paper,
it would seem that the computer game designer has a number
of considerations to make when planning to present a product
with a level of complexity. In learning how to operate a game
or follow a game’s instructions, extraneous cognitive load is a
significant factor and can be minimised by applying tested
instructional design techniques and theories. The appropriate
implementation of visual cues, signalling and highlighting
offer relief in the case of a split-attention effect. The balancing
of audio and visual input channels, or off-loading, would
appear to be a feasible strategy in making a complex game
instruction much more intelligible. It would also seem
possible that game controls and scenario complexity can be
made dynamic and flexible through the utilisation of fading
techniques and progressive disclosure. The theories and
principles discussed here seem to have the potential to be
applied to game design and interactive entertainment in a
constructive manner and further investigation of its
application by the designers of such material would be very
interesting.
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