Cognitive aspects in human computer interaction

Cognitive Aspects in Multimedia Presentation
Introduction:
Multimedia has brought a new dimension to the use of technology in education and training.
Current developments in multimedia which integrate text graphics, audio, video and
animation with instructional interactions has extended the ways in which learners can
manipulate and interact with content material through technology. Through multimedia
presentation, an “author” is able to create and deliver an experience for an “end-user” who is
the consumer of the delivered presentation. The experience can take many forms.
Entertainment, Education, engineering, Healthcare are some of the emerging applications.
Educational titles are one of the dominant product areas of multimedia computing. The
ability of multimedia materials to convey by text, pictures, sound, animation and video, what
is otherwise hard to express and with the use of computer to provide this information in a
form that can be engagingly interactive and easily recast by any aspiring communicator, is
the explanation for the growing popularity of multimedia technology’s role in education.
Audio-visual database can be organised for a variety of cultural, historical and scientific
themes, computer based training courses and so on.
The effectiveness of a process developed for transfer of information, with an aim to increase
the user’s knowledge or skill in the related domain or to improve the ability to solve
problems, depends to large extent, on the vividness of presenting the educative material with
various aids. The clarity of introducing the concepts and a proper logical approach adopted
for imparting learning is also helpful for remembering well. Another factor, the resulting
satisfaction, is also conductive to permanence of learning. A pleasant experience is usually
not easily forgotten. The method of learning thus plays a very vital role, and to be fruitful, it
must not be merely mechanical, but also intelligent. Thus the areas or disciplines like
Psychology and Cognitive Science have the potential to provide massive contribution to
successful multimedia productions. Psychology may be employed to design representations
which will best communicate what the author intends. Basic principles of psychology of
learning must be applied for effective ‘interface’ design that would decide how the user
interacts with the application content or information. Cognitive Science benefits multimedia
by providing a useful model of how intelligent beings process information.
Learning & Learning Models :
In order to design multimedia instructional courseware for the purpose of transfer of
knowledge and information related to a particular subject area, it is necessary to appreciate
the different aspects of learning and learning models.
• Learning is an important facet of education. The term ‘learning’ is used for describing
those internal mental processes (and external activities) which a learner employs for
increasing his/her knowledge (and skill) about some universe of discourse and to
develop the ability to solve problems.
Cognitive Aspects in Multimedia Presentation, MTDRC-DOE 10.1

• The process of learning is multistage. It is highly subjective. A learner has to be
disciplined in order to abstract useful learning. An interested and oriented learner passes
through various stages. As per ancient Indian tradition, knowledge acquisition progresses
through four stages viz.:
Adhyayan (Learning)
Bodh (Understanding)
Aacharan (Use)
Pracharaan (Exposition)
• How people learn, acquire knowledge and develop skills have been debated for years.
For classification of different types of learning, various models and schemes have been
proposed by several authors. These models or categories of learning usually present the
definitions of learning outcomes or objectives. The traditional approach to the
classification of learning processes use broad categories such as knowledge, skill,
attitudes, values etc. A well known model, popularised by Benjamin Bloom and his
collaborators is the three domains of educational objectives ( Ref. 1;Romiszowski,1986).
They have postulated three domains of learning:
Cognitive, Psychomotor and Affective
Domain of Learning Short definition
Cognitive Domain Learning of knowledge, its application,
thinking etc.
Psychomotor Domain Learning practical tasks that require
precision, decision & action
Affective Domain Learning of feelings, preferences, values,
systems, etc.
Table 1
Basic Classification into ‘domains’ of learning. Each of these domains may be further
subdivided into specific categories of learning outcomes or objectives.
Cognitive Domain of Learning :
Within the interactive learning field, an emphasis on the underlying theory involving the
cognitive approach is the current trend. Attention is towards cognitive models focusing on
the notions of situated, contextual and discovery learning, supported by content structuring,
learning from errors, explaining and reflecting (Ref.2). Learning as an activity starts with
exposure and progresses in a related pedagogical environment with the help of cognitive
process. Pedagogical environment comprises of study material and external as well as
internal cognitive tools. Study material includes multiple forms of subject contents. The
quickly expanding field of cognitive psychology throws a very useful light on the learning

process (Ref.3). Learning has been described as a multistage process, which results into
formation of higher level mental constructs known as ‘cognitive maps’.
• Learning results into mental encoding of knowledge, which is internally represented by
multidimensional higher level mental constructs or cognitive maps.
• Faithful external representation of these internal cognitive maps results into effective
teaching. It can be said that the designers of the multimedia learning systems should
formulate schemes to externalize the cognitive maps. The success would depend on evolving
novel knowledge representation schemes.
• A learning system can enhance the creation of cognitive maps by creating interest and
orienting a learner for detailed analysis - through a well structured study material. Well
structured study material increases the learner’s freedom to access the content as per their
requirement. Searchability, flexibility and even utility of information largely depend upon its
structure.
• The aim a high quality learning system designer should be to help the learner to create
personal ‘cognitive maps’ to unify the total context of the knowledge (synthesis). Such maps
are capable of very efficiently encoding the knowledge and are generally long lasting.
The cognitive domain of learning can be further subdivided into specific categories of
learning outcomes or objectives :
Category name Brief Description
Knowledge The remembering of previously learned
material. The lowest level of learning
outcomes in the cognitive domain.
Comprehension Ability to grasp the meaning of material.
Interpreting, paraphrasing, explaining.
Application Ability to use learned material in new and
concrete situations. Applications,
demonstrations.
Analysis Ability to break down material into its
component parts, so that it’s organisational
structure may be understood.
Synthesis Ability to put ideas together to form a new
whole. Proposes, integrates, designs.
Evaluation The ability to judge the value of material for
a given purpose.
Table 2: Subclassifications in the Cognitive Domain.

Knowledge :
Information acquired and stored in an
organised manner in mind
Skill :
The capacity to do something (perform) with
a given degree of effectiveness and
efficiency
1. Knowledge of the steps to be followed in
order to divide two numbers
Ability to divide two numbers with necessary
degree of speed and precision.
2. Knowledge of Newton’s laws of motion. Ability to solve problems in mechanics
correctly by applying the laws.
3.Knowledge of basic principles of human
relations that apply to supervision
Ability to resolve conflicts between staff and
supervision tactfully, justly, fasts. etc.
Table 3. Knowledge & skill : definitions
Some other aspects of learning may also be distinguished which influence the processing of
information in the human brain and the development of cognitive skill. These are :
• Retention
• Problem solving
• Learning Style
Retention :
All of us seem to be subject to some sort of constraints on our thinking. It’s so often that we
forget ! This results from the way in which information is stored and modeled in our brain.
Therefore it is worth looking at our knowledge processing model and identifies the effects
this might have on the development of our cognitive skill.
Memory organisation :
The retention of information in the memory depends on the memory structure. This seems
hierarchical with three distinct connected areas as shown in Fig.1.
Fig.1
Working Memory
Long Term Memory (Large
capacity, slow access)
From Senses

A limited capacity, fast access, short term memory : Input from the senses is received here
for initial processing . This memory is comparable with registers in a computer; it is used for
information processing and not for information storage.
A larger capacity, working memory area: This memory has a longer access time than short
term memory. It is used for information processing but can retain information for longer
periods than short term memory. It is not used for long term information retention. By
analogy with the computer, this is like the volatile store where information is maintained for
the duration of a computation.
Long term memory: This has a large capacity, relatively slow access time and unreliable
retrieval mechanisms (we forget things!). Long term memory is used for the ‘permanent’
storage of information. To continue the analogy, long term memory is like disk memory on a
computer.
Problem information is received in short term memory and is integrated with exiting,
relevant information from long term memory in working memory. The result of this
integration forms the basis for problem solutions, which may be stored in long term memory
for future use. Of course the solution may be incorrect which involves future revision of the
long term memory. However, old incorrect information is not completely discarded but is
retained to help avoid repeating the same mistakes.
The limited size of short term memory constrains our cognitive processes. It is proposed that
human short term memory can handle about 5 to 9 items or ‘chunks’ of information at a
time. The chunks may be large or small in terms of information content. The total amount
of information that may be held in short term memory is increased by the structuring of the
perceived information into meaningful chunks.
If a problem involves the input of more information than the short term memory can handle,
there has to be information processing and transfer during the input process. This can result
in information being lost and errors arising because this information processing cannot keep
up with the memory input. This is a particular problem when new information is being
processed. For example, if we are presented with pictures of common animals, these can be
processed quickly because they have been known since childhood. On the other hand, if we
are presented with descriptions of new software components, it takes much longer to work
out what these mean.
Information enters short term memory and is processed before being stored in long term
memory. We don’t store raw information but store information abstractions, which we call
knowledge. Although the distinction between information and knowledge is not a rigid one,
a possible view is that neural information processing involves the integration of new and
existing information to create knowledge. Further the Knowledge acquired and stored in
long term memory may be ‘semantic knowledge’ which is the knowledge of concepts
acquired by experience and through active learning where new information is consciously
integrated with existing semantic structure. On the other hand, the stored knowledge may be

‘syntactic knowledge’ much closer to detailed information. New syntactic knowledge is not
immediately integrated with existing knowledge but may interfere with it. It can only be
arbitrarily added to that knowledge.
In the light of memory organisation involving short term and long term human memory, the
four steps in learning are also described as Attention, Rehearsal, Encoding, and Retrieval .
Fig.2 Major steps in the learning process
Problem Solving Process :
While solving a problem by processing a body of information, different types of
information, different types of procedures or mental operations are performed by the learner.
For example L.N. Landa (Ref.1) has suggested a classification of thought processes into :
Algorithmic and Heuristic
Algorithmic
The correct solution of a given type of problem will always be achieved by the execution of
a fixed sequence of specific operations. Landa shows that some categories of problems (e.g.
planning grammatically correct sentences) were almost entirely solvable by algorithmic
procedures.
Heuristic
To solve a specific problem, different persons will plan different procedures, though they
may use the same basic principles as the starting point. Many problems of a given type ( but
not necessarily all problems) may thus be solved by different procedures. The solution of
problems in geometry requires heuristic procedures.
Learning Style
Some authors focused on the general strategies of learning that lead to success. For example,
two characteristic types of learning strategy have been identified by Gordon Pask : Serialist
and Wholist.(Ref.1)
Attention Rehearsal
Retrieval Encoding

Serialist
The inclination to follow a linear path of step-by-step deduction or development of a topic.
Wholist
The inclination to ‘jump ahead’ in an attempt to get the ‘whole picture’ of the topic, coming
back to study details only as and when it turns out necessary for comprehension.
Pask observed that
- Individual learner tended to prefer strongly one or the other style.
- Success in learning was much superior when information was presented in a form that
facilitated the adoption of the preferred learning style.
Affective and Cognitive domain learning
Our perceptions of experience are primarily characterised in terms of our emotional
responses. Experience mixed with emotion or feelings are well remembered - all the details
are retained in mind. Learning outcome is improved if we approach by emotional
association. Therefore ‘affective’ domain factors of learning should not be neglected or
ignored in the planning, design and development of learning material in general and of
multimedia projects in particular. The proposition that affect guides emotional responses is
a concept over three decades old (Ref.Tomkins,1961) and the literature which does address
this central area suggests that affect and cognition are inextricably intertwined in learning
processes. The clear indication in contemporary literature is that design and development
which addresses only the cognitive aspect of learning processes without attending to the
affective domain factors neglects a major component of any recipe for success. (Ref.4)
As far as learning is concerned, there is a need to tackle the issues of presenting materials
for two separate camps - Education and Entertainment. On one extremity, we find strictly
cognition oriented materials with dry and unengaging content for the learner, while at the
other end, we find material which seem driven by high technology but of low educational
value. While there is an obviousness to the statement that ‘learning and enjoyment are not
mutually exclusive” (4), the successful creation of such materials require a highly skilled
balancing act - on the one hand, interest and intellectual activity and, on the other hand,
liking and positive stimulation of the affective domain. As pointed out by David Goldfayl
(Ref.4), serious minded learning need not be treated as being only of the strictly cognitive,
furrow-browed kind. The learner should not identify the presentation as a courseware having
more matter with less art. The materials designed and developed for an entertainment
package on the other hand, should not ultimately appear to the user to be an ‘unremembered
pleasure’.

When the full range of emotional responses are considered, the effects which could be
considered as ‘positive’ include only a few like interest, enjoyment and surprise (Ref.4).
These three positive affects are of course, outcomes likely to be achieved by successful
training material. This type of engagement offers absolutely no guarantee of cognitively
meaningful interaction taking place. Yet neither does it suggest that it will not take place.
The ‘negative’ affects cited (Ref.4) are fear, anger, distress, shame, contempt and disgust.
What remains clear and central is that instances where any of these negative affects are
elicited by multimedia, this will almost certainly guarantee that cognitively meaningful
engagement will not take place. Multimedia borrows its philosophy from various sources
and the methodology followed for the creation of multimedia materials should be based on
pedagogically sound theoretical and pragmatic approach incorporating a balance of
cognitive and affective factors of learning.
Role of the creator of Multimedia (MM) learning material
As a matter of fact, the role to be played by the creators of multimedia learning material
should not substantially differ from the role, which they play in the preparation of any other
learning material. Program content can be defined as the specific messages, facts or
information, pictures, data etc. presented through the MM application. However, the very
nature of the MM environment does alter two central factors, that is
• Learner preconceptions of the medium
• Awareness and use of the emerging presentational qualities.
Both of these areas will have immense impact on the level and quality of affective
engagement of learners and as such, need to be addressed at the earliest possible time in the
life cycle of a MM project.
Preconceptions
A learner’s perception of any medium will have a great impact upon the amount of mental
effort he would invest. It is worth noting that almost all new computers are now sold to the
domestic market with built-in CD ROM players and it is no idle fact that most of these are
primarily used for some form of guided game playing. This suggests an increasingly
powerful impact upon learner’s perception of the medium when encountering MM with
genuine educational objectives. Overly dry educational content does not seem to be any kind
of answer to this. Rather it seems that the judicious adoption of appropriate popular
presentational forms and genres will most likely offer the best results in terms of learner
engagement.
It remains incumbent upon creators of educational materials in general, and MM in
particular, to clearly and unambiguously frame the content in such a way that it is not only
appropriate to the affective needs of the learner, but also to the type of cognitive demands
that will be expected of them. This naturally means knowing one’s target population well
and incorporating iterative feedback process throughout the early formative evaluation so as
to fine tune the content accordingly.

Presentational Qualities
The mode of approaching the formative stages of material production has a significant
impact on MM production qualities. The development process is time consuming, but the
production qualities that it projects are very quickly judged by learners. It can offer a
superbly interesting and revealing experience by presenting events and environments that
otherwise may not be possible. Events can be seen differently than in real life, such as slow-
motion. Connections and grounding can be succinctly made through auditory, visual and
textual information and cues. For achieving the desired educational objectives imaginative,
exciting and creative interconnections can be made. It is the complexity associated with
these factors that necessitates adequate skill in eliciting affective domain factors in learners.
Clearly, such choices must be made early in the decision making process, since changing
them after or during actual production is both time consuming and expensive. Therefore, it
would be appropriate to accomplish the script writing in the early pre-production stage itself
combining affective and cognitive factors. Since insight and understanding occur at the
deepest levels when learners are affectivity engaged, the art of script writing plays an
important role in the design and development of successful MM projects [Ref. 4].
Multimedia Educational Software Modeling
There is a demand of suitable models for applying interactive MM technology to develop
educational software due to lack of enough maturity in this area [Ref. 3]. Though the
educationists have experimented and utilised the upcoming communication technologies, it
is interesting to note that `Books' still remain the most popular medium for learning
("Swadhyaya"). Though available at affordable cost, Video or Audio cassettes has not
become a very popular educational technical aid for focused learning. But, it is also worth
noting that digital technology is helping us today to redefine the notion of the `Book' from a
static and linear collection of limited visual content to a dynamic and non-linear corpus of
large body of multimedia content. Recently, S. Goel has proposed a model [Ref. 3, 1998]
which has evolved out of the desire to support the learning process at all stages and extend
the `Book' paradigm. The proposed model tries to free the `Book' from the constraints of
paper and takes advantage of the novel features of the new technology realising the full
potential of the computer as a general purpose simulator. Computer's ability to store large
volumes of instantly available data to represent any structure or behavior, and to integrate
multiple elements are the underlying strengths on which the model is based upon.
- It tries to harness the power of interaction multimedia by offering exclusive study
materials, with a special attention paid to enhance the interactivity.
- It proposes effective mechanisms to facilitate uniform and quick exploration, rendering
and analysis of large digital corpus of educational content.
- Emphasises on properly dealing the issues related to Media component selection. With
the help of digitisation device pictures, audio, video and textual contents are

implementable. Each type of technological medium influences significantly the
message that it will convey. With careful planning, the physical data storage capability
of a CD ROM can be best utilised. On an average, experienced readers read
approximately 20 pages in an hour and a full CD ROM may provide a study material in
printed text for about 10,000 hours (more than 2 lakh pages). Hence, most of the space
is usually to be located for storing other media components like pictures, audio, video
and animations.
- Video should be used very selectively, since it consumes a lot of space. Ideally, it
should be used to demonstrate kinetic action. A well conceived mix of still pictures,
music and oral commentary often serve the purpose equally well. However, selective
uses of small video clippings greatly enhances the learning possibilities.
Hence, in order to make it a really successful pedagogical medium, the interactive MM is
recommended to be used as a meta-medium for the development of learning aids based on a
design model, which is primarily an extension of the book paradigm. In short, it should
include the features of other educational technologies and the novel content processing and
searching possibilities being offered by the computers.
The extended `Book' paradigm may be made to support a learning process in which several
pathways are provided though the material creating a `non-linear' experience so that the end
user can make choice about where to go in the presentation as well as how long to view each
screen. The end user's choices are frequently referred to as `navigating'. Authoring
software’s used by the instruction designers frequently support testing of the end user,
maintaining individual scores and tracking the paths that users take through the material.
Some authoring systems are intended for the creation of `hypertext' documents to mean
non-sequential writing which enable to make links from one place in a document to another,
such as a reference to a textual term that can be achieved as a hot button to take the reader to
full explanation of the term. Another feature might be the capability to search all of the text
in the entire document for all the occurrences of a specific word or phrase, known as `index
search'. The result of the authoring process in a MM courseware development is a structure
of elements, linked in various paths determined by the author. This structure appears to the
end user as a series of screens containing information in various forms with interactive
options available through icons, keyboards or buttons.
MM Presentation Format
Once the MM courseware script is prepared, the author has to decide on the format for
presentation of the information on the computer screen. A possible presentation format
could be any one of the following for a particular screen.
• Text screen (window) consisting of text only.
• Graphic screen (window) - could be a static display of image (which may have several
visual components), or a dynamic display using animation or simulation technique or a
recorded video clipping synchronised with audio clauses.

• Combination of text and graphic screen (window) i.e. a part of the screen would be used
for textual presentation and the remaining for graphic display.
• Multiple windows e.g. one window for text, one for graphics or video clippings, one for
dialogue between the learner and the computer. Only one window would be active at a
time.
• Hypertext i.e. some of the keywords or portions of graphic regions are buttoned. The
activation of these buttons through keyboard or pointing device like mouse switches to
another screen wherein more detailed information regarding the keyword or the graphic
region may be presented.
In each of the above formats of presentation the selection of color plays an important part so
far as aesthetics are concerned. To break the visual monotony sometimes keywords are
highlighted or various fonts may be used. Use of overlapping windows with zoom and pan
facility enhances the presentation quality of a screen.
Interactivity Goals
The conceived MM model is translated into separate and distinctly different interfaces for
the author and the end user. The author interface typically has a suite of on-screen tools
available through menus, icons, text prompts or other options, which can be evoked to create
and place elements on the screen. The end user’s interface is defined by the elements that the
author has invented. For example, a screen that includes text in paragraphs, a scanned image
and audio segments may have hot buttons or sensitive regions on the screen that the end user
can select to interact with the screen elements, navigate to other parts of the presentation or
simply set "help". In controlling individual progress through a course, learners are usually
provided with a form of performance support mechanism, usually in the form of context
sensitive `help' providing relevant information. The idea implicit in this model is that the end
user
- will not add to or modify the content of the experience
- will interact with it only on the terms set by the author.
It is left to human creativity to use the technological possibilities to the fullest and use the
technology in the most meaningful way. An active learner applies various external as well as
internal cognitive tools and processes and explores the contents of the study material. A
computer aided cognition support system should try to simulate and extend these tools and
processes as well as offer an integrated corpus of study material. A set of proposed
simulation goals are :

A) Study Material
The amount of emphasis to different kinds of study material varies from discipline to
discipline. Generally, learners use following types of study materials :
1. Visual Material
- Pictorial material : photographs, slides, drawings, maps, film strips, video and synthetic
animation.
- Written material : books, manuscripts, thesaurus, dictionary.
- Real or reconstructed 3D objects.
2. Oral Material : commentaries, recitations, chanting, and music.
B) Cognitive Tools
- External Cognitive Tools
- Search supports Devices e.g. Indices and Catalogues
- Study material Inspection Devices e.g. slide-viewer, video player, audio player,
computer.
- Recording Devices e.g. notebooks, drawing board
- Measurement and Experimentation Devices.
- Cut, Paste and Duplication Devices.
- Direct Communication Devices.
- Internal Cognitive Tools
- Multidimensional Mental Space of Analysis
- Cognitive Maps.
C) Cognitive Processes
- External Cognitive Processes
- Navigation (Linear, Non-linear)
- Querying
- Internal Cognitive Processes
- Pattern Matching
- Recollection
- Comparison
- Contextualisation
- Abstraction.

Inter-disciplinary and Holistic studies demand contextual access to visual, oral and textual
sources. Designers have been advised in [2] to be specifically ready to spend substantial
intellectual effort in content structuring. The computer relies upon these structures to
execute various search related tasks and relieves the learner from lots of mechanical
activities.
User Interaction Modes
Learning is a multi-stage process and different stages of learning process demand different
kinds of support from the learning aids. A complete `cognition support system' should offer
support features for all these stages. Hence, the user should be allowed to interact with the
system in the following modes :
a) Presentation mode (story telling)
b) Exploration mode (In-depth study)
c) Abstraction mode (Internalisation)
An optional feature of on-line continuous evaluation can be included to offer feedback to the
learners.
Presentation Mode (Story Telling)
This mode can be designed such that the user is at most an active receiver. Efforts should be
made to give a persuasive discourse to the user in order to make him interested in the subject
and explore the system in more academic modes.
An enjoyable presentation can be designed based on the use of extended video.
• A system may have multiple narrations with different focus. Several individually useful
sub-narrations about key concepts may be embedded in the presentation.
• The sequence of individually significant `discourse clauses' needs to be carefully
planned. Narrative design is a highly creative activity, like a good plot, it should have a
beginning, middle and an end. It should not be so long that one forgets the beginning
before reaching the end.
• A discourse clause can be primarily attributed either by Audio, Visual or Audio-Visual
element. Supporting visuals can be synchronised with audio clauses and audio elements
can support a visual clause.
• A visual clause can either be a static visual frame, a series of static visual frames or a
kinetic visual sequence. The static frames can themselves have several visual
components. A recorded video clipping or a synthetic animation sequence can be used as
kinetic visual sequence. The user is usually offered the facilities to step through the
discourse clause and control the speed and direction of presentation.

Exploration Mode (In-depth Study)
This mode is aimed at offering detailed `analysis' and in-depth information to the interested
user. Only active learners get access to this mode. Active participation by the user is
expected in order to get the maximum information and knowledge. A navigational approach
to information retrieval is facilitated by offering a universal set of controls for examining
information of different media types. Thus, the learner has the options to explore and move
about an environment and the challenge of the developers lies in providing appropriate
control options, which support this interactive mode.
Abstraction Mode (Internalisation)
This is a very significant mode as it aims to consolidate the learning and offer the `complete
picture' to the user providing assistance and necessary guidance in `synthesis'. After
synthesis, the `learned user' will `see' newer things in the Presentation and Exploration
mode. The design objective of this mode should be to simulate and externalise the internal
structure of content experts in terms of cognitive maps - offering key concepts and inter
concept relationships. It should also offer tools for externalisation of personal cognitive
maps.
Mode Integration
A learner does not make a progression through learning stages in a rigid order. An active
learner tends to move back and forth between these stages. This component, i.e. sequence
control is significant which refers to the order in which the content is viewed. Hence, during
the course of any mode, the user should be offered the facilities for appropriately switching
to either of the other modes. For example, during a discourse in the Presentation mode, the
learner may get interested in knowing more about any of the presented items. Thus, while
the learner is oriented by offering a sequence of Audio-Visual discourse clauses, provision
should be offered to him to switch to Exploration mode and enter the relevant database.
Content presented during one mode can be used as the context to switch to another mode.
This facilitates content based seamless integration of all the modes [3]. The sequence control
is often defined in terms of being able to move to and from (forward and backward) along a
linear sequence of context or provided by hypertext and hypermedia links.
System Quality
The three major parameters along which the `quality' of a computer aided cognition support
system for the Presentation, Exploration and Abstraction modes is proposed to be evaluated
[3] are :
- Content comprehensiveness
- Interactivity features
- Mixmedia presentation.

System Quality
Content Comprehensiveness
Overall system quality is proposed to be quantified as the volume of rectangular box carved
out of the proposed three dimensional normalised coordinate system i.e.
Qs = Qc * QM * Q1 ---------- [Eq. 1]
where, Qs = System Quality [0.1]
Qc = Quality of Content comprehensiveness [0.. 1]
QM = Quality of Mix media presentation of the content [0..1]
Q^ = Quality of Interactivity [0..1]
It can be seen that even a singular weakness on any of these three fronts will result into a
very low quality system. Hence, in order to develop high quality system, it is very important
that multidisciplinary teams closely work towards improving the quality of all the
parameters. The foundation of design should combine the knowledge of art and science in
`useful compromise'.
Content Comprehensiveness is the most important of the three parameters. It is determined
by Authenticity, Richness and Structuring of the content. Well structured study material
increases the learners' freedom to access the content as per their requirement. Searchability,
flexibility and even the utility of information largely depends upon its structure. Flexibility
of Mechanised Content Access can only be harnessed by supplementing the Content with a
rigorous Content Structure. The Content Structure consists of internal as well as external
Mix Media Presentation
Interactivity

structuring elements. Internal structuring elements are embedded into the content itself while
external elements provide several kinds of indices for accessing the content.
The Quality of Content Comprehensiveness can evaluated as follows :
QC = QCS * QCR * QCA
Where, QC = Quality of Content comprehensiveness
QCS = Quality of Content Structuring [0..1]
QCR = Quality of Content Richness [0..1]
QCA = Quality of Content Authenticity [0..1]
It can be seen that even very rich and authentic collection of content is not comprehensive
until it is structured well.
Interactivity Quality
The computer can be used as meta-medium and interactive devices can be developed to
simulate cognitive tools and cognitive processes at different learning stages. These devices
provide various kinds of user controls during Presentation, Exploration and Abstraction
mode. User-ease and User-empowerment are two conflicting and complementary
parameters.
Richness
Authenticity

Fig 4 : Interactivity Quality
User Empowerment
User Ease
Level of User-empowerment depends upon the range and utility of devices provided by the
system. Consistency of the system with traditional and natural learning tools, system
feedback and inter-device consistency determine the degree of User-ease.
Quality of system devices can be modeled as follows :
QI = QIP * QIE
Where, QI = Quality of Interactivity
QIP = Quality of user-empowerment by Interactive devices [0..1]
QIE = Quality of user-Ease of Interactive devices [0..1]
Mix media presentation
Mixed media presentation of information further increases the learning possibilities. Quality
of Mix media presentation of content depends upon media integration and aesthetic appeal
of media components.
Elements of User Interface
The user has no access to the interior of the computer system except through the user
interface. User interface allows the human user to interact with the computer and includes
the parts of the computer hardware which the user can interact with e.g. Screen, Keyboard,
Mouse etc. as well as the images which are visible on the screen eg. Windows, menus, etc.
The purpose of the user interface is to make the computer system ‘usable’ by the user. In
otherwords, the most critical quality of a user interface is its ‘usability’.
• Usability includes being easy to learn and effective to use.
• Usability involves adapting the computer system to human beings that use it.

• Usability raises various complicated psychological issues of human memory,
perception and conceptualisation.
Graphical User Interface (GUI)
User interfaces which rely on windows, iconic (pictorial) representations of entities, pull-
down or pop-up menus and pointing devices are now commonplace on PC’s and work
stations. The term “WIMP interface” (derived from Windows, Icons, Menus and Pointing)
was used as a mnemonic for this type of interface but they are now called “graphical user
interface (GUI’s). They are characterised by :
Multiple windows allowing different information to be displayed simultaneously on the
user’s screen.
1. Iconic information representation. Icons represent files or processes.
2. Command selection via menus rather than a command language.
3. A pointing device such as mouse for selecting choices from a menu or indicating
items of interest in a window.
4. Support for graphical as well as textual information display.
An example of the interface style is shown in Fig. 2 , two windows are displayed on the
screen with each window showing a collection of documents. The main advantages of GUI
are
• They are easy to learn and use. Users with no computing experience can learn to use
the interface after a brief training session.
• The user has multiple screens (windows) for system interaction. Switching from one
task to another is possible without loosing sight of information generated during the
first task.
• GUI can use Menus and provide user interface objects like buttons, lights and sliders.
Menu systems
♦ In a menu interface, users select one of a number of possibilities and indicate their
choice to the machine. Menu names in windows appear in a “menu bar” at the top of the
application. Users may
⇒ Type the name or the identifier of the selection.
⇒ Point at it with a graphical input device. Clicking on a menu title with the mouse
button pulls down a menu of choice. Pull down menus list action commands

which are selected either by clicking on them with a mouse or by typing the
underlined letter. Some applications also user pop-up menus.
⇒ Point at the selection with a finger or a pen on touch-sensitive terminals.
♦ Menu based systems have several advantages :
⇒ Users need not know the precise command names. They are always presented
with a valid command list are they select from this.
⇒ Typing effort is minimal. This is important for those users who cannot type
quickly.
⇒ User errors are trapped by the interface.
⇒ Context-dependent help can be provided.
♦ Menus with a large number of possible choices are organised providing the users with
♦ “Scrolling menus” : when a choice is not displayed on a menu, the menu scrolls on
command from the user to display the next set of choices. Vertical scroll bars are usually
provided for lists too long. Horizontal scroll bars can be provided if the box is not shown
in full.
♦ “Cascading menu’s” : when a menu item is selected, this causes a further menu to be
displayed adjacent to it. Some action commands, indicated by a right-pointing arrow.
e.g. select a cascading menu of further menu choices.
♦ “Hierarchical menus” : the menus are organised in a hierarchy and selecting a menu item
causes the current menu to be replaced by another menu representing its subtree. Such
menus can manage very large numbers of choices.
Buttons
Picking a button always causes a single action to be initiated. The standard windows
interface uses command buttons (rectangular-shaped buttons containing a textual label (or
picture) depressed. An option button, also known as a radio button, represents a single
choice in a limited set of mutually exclusive choices. When one option in the group is
selected, the others are deselected.
Lights
♦ Lights are activated to show some action is taking place.
Slides

Sliders are input devices used to set a specific input value. They are used to display and
adjust values on continuous dimensions, such as a varying color from white to black, or
volume from soft to loud. The indicator shows the present value, and the user drags the
slider with a mouse along the scale to set the desired value.
All these elements of user interface may be adapted in the development of the interactive
multimedia user interface. These techniques need to be integrated into a learning framework
where the users are not just passive objects to be manipulated and due consideration and
attention have to be made to cater for their feelings, desires and thoughts. Since the
“Usability” of the interaction interface is both :
♦ the most important quality, and
♦ difficult to achieve
the designers need strong design techniques to help us.
The selection of proper styles of interaction is an important aspect of design.
Interaction Style
♦ Impact of interaction style
♦ Match between user’s need and interaction style is critical to usability.
♦ Each style offers a way to organising the functionality, managing user’s input
and presenting information.
♦ Primary styles of interaction
♦ Menu driven interaction
♦ Question-and-answer
♦ Function key interaction
♦ Voice-based interaction
Menu driven interaction
♦ Users given a choice of options and the selection may generate a further choice
♦ Range of options may be large.
Question-and-answer
♦ Optional for data entry tasks performed by unskilled users.
♦ Lends itself to very procedural tasks
♦ Good for getting one bit of information at a time
♦ Slow and unreliable for non-typists.
♦ No natural menus of correcting errors.

Function Key interaction
♦ Similar to Q and A but with dedicated technology e.g. pushbuttons, function keys.
♦ Users must be guided by prompts and messages.
♦ Must be operated in a particular order
Voice based interaction
♦ Users are presented with a series of options from which to choose.
♦ Users make selections via button presses.
♦ Relies on user’s memory.
♦ Very slow to get through the dialogue.
Other styles of interaction
♦ Direct manipulation
♦ Linguistic interaction
Direct manipulation style
♦ A direct manipulation interface presents users with a model of their information space
and they modify their information by direct action.
♦ Typical user learning time is short.
♦ Users get immediate feedback on their actions so mistakes can be detected and
corrected very quickly.
♦ Graphical Direct Manipulation
♦ Information is displayed in the form of graphical objects
♦ Users can manipulate objects, e.g. Deletion of an entity involves dragging its
icon into the trashcan.
♦ Form Fill In
♦ Users can directly fill in specific fields.
♦ Restricted to textual data
♦ Best suited to skillful workers
♦ Supports updating existing entries.
Linguistic Interaction
♦ Command Line Interaction
♦ Users type in a command and the system responds (usually with more text)
♦ Useful for complex data entry and retrieval tasks.

♦ A fast Interaction style, once user knows the language.
♦ Major drawback in the amount of training required.
♦ Natural Language
♦ User types in a command in English and the system responds
♦ Interprets simple statements typed by users in a “natural” language.
♦ Most approachable because its more English like (other native language)
References
1. Romiszowski, A.J,1986 Developing Auto-instructional Materials,
Kogan Page, London/Nichols Publishing, New York
2. Sims R., Hedberg.J, : Dimensions of Learner Control
A Reppraisal for Interactive Multimedia Instruction
University of Technology
r.sims@uts.edu.uk
3. Goel. S, IGNCA : A model Design for Computer Aided Cognition
Support System (1998)
4. Goldfayl, D. : Affective and Cognitive Domain Learning with
Multimedia : Two Sides of the Same Coin
Victoria University of Technology
dgoldfayl@essex.vnt.edu.au
5. Godfrey R. New Wine in Old Bottles : Multimedia Design
Methodology
University of Tasmania
B.Godfrey@appcomp.utas.edu.au
6. Mackay F. A Survey of the State-of -the -Art in interactive
Multimedia
Interactive Multimedia Report,JRCASE,1994
7. Datta K,Goswami SK,Ghoshal TK,Das
G,Bhattacharya S.
Computer Based Instruction
Courseware Documentation
School of Education Technology
Jadavpur University
Calcutta 32
8. Ian, S. Software Engineering
Addison -Wesley Publishing Co.

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