External and Internal Representations in the Acquisition and Use of Knowledge:
Visualization Effects on Mental Model Construction
Wolfgang Schnotz, Christian Kurscher. Instructional Science. Amsterdam: May 2008. Vol. 36,
Iss. 3; pp. 175-190.
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Abstract
A noteworthy article on a critical educational domain. This knol, “External and Internal
Representations in the Acquisition and Use of Knowledge: Visualization Effects on Mental
Model Construction” written by Wolfgang Schnotz and Christian Kurscher (2008), investigates
whether different formats of visualizing information result in different mental models
constructed in learning from pictures, whether the different mental models precede to different
patterns of performance in subsequently presented tasks, and how these visualization effects can
be amended by further external representations during task performance. The authors present a
line of argument for educators and practitioners to have an alternative view in multimedia
learning using integrated model of text and picture comprehension earlier proposed by Schnotz
and Bannert (2003) which the authors believe is necessary in order to understand “how multiple
external representations interact with internal (mental) multiple representations not only in the
acquisition of knowledge, but also in using of the acquired knowledge, when an individual can
rely on his/her own internal mental representations as well as on other external representations in
order to solve specific tasks at hand” (Schnotz & Kurschner, 2008). Therefore, both Schnotz and
Kurscher are keen to point out that the form of visualization has an effect on the structure of the
mental modal constructed during learning, which subsequently influences the patterns of
performance that individuals show after learning. They are also keen to explain the effectiveness
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of further external representations during the usage of acquired knowledge. My overall
impression is that the authors have presented the case in an enlightening way while expressing it
in a clear, well-structured and succinct approach.
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Introduction & Problem Identification
In this article the authors have relied on Paivio’s (1986) dual-coding theory which
assumes that human cognition includes verbal and pictorial subsystems. They are interrelated,
therefore, memory is enhanced as more elaboration can be obtained. Schnotz and Kurschner also
site Mayer’s (2001, 2005) cognitive theory of multimedia learning which assumes that humans
are active sense-makers. Through engagement in active cognitive processing, they construct
related knowledge structure from their available external information and prior knowledge.
However, Schnotz and Kurschner assert these theories as simplistic and have yet to explain some
principles of representations. With this notion, the authors seek for an alternative view and
further explanation on multiple external representations and multimedia learning by employing
the integrated model of text and picture comprehension earlier proposed by Schnotz and Bannert
(2003). This model claims that “pictures facilitate learning only if the subject matter is visualized
in a task-appropriate way, otherwise learning may be interfered” (Schnotz and Bannert, 2003).
Thus, it is significant to investigate whether different formats of visualizing information result in
different mental models constructed in learning from pictures, whether the different mental
models proceed to different patterns of performance in subsequently presented tasks, and how
these visualization effects can be modified by further external representations during task
performance.
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The Methodology Employed
3.1
Sample and Instrument
For the purpose of the study, Schnots and Kurscher had identified 80 university students
majoring in different fields and randomly assigned them to four groups of 20 persons to
correspond to four experimental conditions. There were two factors being tested. First, it was the
kind of picture used for visualizing the learning content. The second factor was the availability of
an external source of information during the process of solving tasks after learning. The learning
material was a text of 2750 words about the existence of different daytimes and dates on earth
combined with different sets of pictures as external visualization of the learning content, namely
either carpet pictures or circle pictures.
3.2
Procedure and Scoring
The experiment encompassed three different phases; testing learning prerequisite phase,
learning phase and task performance phase. During task performance phase, an assessment of
comprehension on 16 time difference tasks (carpet picture groups) and 16 circumnavigation tasks
(circle picture groups) were given to the subjects to be solved. At this stage too, one half of the
subjects were given access to external representation aid table (Table 1) while the other half
without it and therefore had to rely on their internal mental representations of the learning
material. The percent of correctly solved time difference and circumnavigation tasks was used as
to determine the score for each visual format.
3.3
Results
The mean and standard deviations of learning with the factors visualization format,
external representation and the kind of task can be seen in Table 3 of the article. Table 3 showed
that participants who had learned with carpet pictures performed better with time difference tasks
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(matching task) than participants who learned with circle pictures. In addition, participants who
had learned with circle pictures performed better with circumnavigation tasks (matching task)
than participants who learned with carpet pictures. These results, thus, support Schnotz and
Kurschner’s hypotheses that different formats of visualizing information result in different
mental models constructed in learning from picture and different mental models lead to different
patterns of performance in subsequently presented tasks.
On the other hand, information in Figure 4 indicated that the effect of form of
visualization on patterns of performance after learning was significantly reduces when further
external representations are available during the usage of acquired knowledge. Expectedly, the
result also supports the authors’ hypothesis that visualization effects can be modified by further
external representations during task performance.
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Conclusion
Through this study, Schnotz and Kurschner have shed some lights into a critical issue in
the area of multiple representations and multimedia learning. The results of their experiments
showed that the form of visualization one receives has an effect on his/her mental model
structure during learning and influences on the pattern of performance after learning. Their
findings also reveal that a combination of task and learning with appropriate visual
representation will foster the learning of content. In contrast, a combination of task and learning
with inappropriate visual representation may rather interfere the learning of content. Their
findings here support Schnotz and Bannert’s (2003) notion that “pictures facilitate learning only
if the subject matter is visualized in a task-appropriate way, otherwise learning may be
interfered”.
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These findings are, in fact, an eye-opener into understanding multiple external
representations and multimedia learning because they are more elaborated. Schnotz and
Kurschner claimed that Paivio’s (1986) dual-coding theory as too simplistic as the theory
attempts at giving equal weight to both verbal and pictorial subsystems but ignores the critical
contention of the appropriateness of multiple external visual representations in fostering learning.
With these findings, too, Schnotz and Kurschner helped to explain and elaborate some part of
Mayer’s (2001, 2005) cognitive theory of multimedia learning that they found questionable.
Further, the study had been well-conducted and articulated. However, for the benefit of
better validation and generalization of the findings, the same study can be replicated on different
area of studies and different groups of learners in various situations. In my conception, this will
bring us all to a new, different or even better understanding of multiple external representation
and multimedia learning. In addition, Schnotz and Lowe (2003) also proposed researchers in the
field of multimedia learning and visual representations to further investigate the complex
interplay between external representations and internal (mental) representations involved in
learning from multimedia as they claim that it is a rapidly expanding area of research and has
such important implications for future educational practice.
Nevertheless, I believe that Schnortz and Kurschner’s findings had made a breakthrough
in multiple external representations and multimedia learning. Educators and education
practitioners now need to come to understand that it is important not to only supply multiple
external representations to facilitate learning of content but also to consider selecting the
appropriate form of visualizations to pair with the targeted tasks. Larkin and Simon (1987) once
said that a picture can be worth more than 10 000 words. Thus, this careful and selective conduct
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is a fundamental as it is a determinant factor to ascertain the ease or difficulty of learning.
Otherwise, it may turn useless because learning may be interfered.
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References
Larkin, J., & Simon, H. (1987). Why a diagram is (sometimes) worth ten thousands words?
Cognitive Sciences, 11, 65-99
Mayer, R. (2001). Multimedia learning. New York: Cambridge University Press.
Mayer, R. (2005). The Cambridge handbook of multimedia learning. Cambridge: Cambridge
University Press.
Paivio, A. (1986). Mental representations: A dual-coding approach. New York: Oxford
University Press.
Schnotz, W. (2005). An integrated model of text and picture comprehension. In R. E. Mayer
(Ed.), Cambridge handbook of multimedia learning. (pp. 49-69). Cambridge: Cambridge
University Press.
Schnotz, W., Bannert, M. (2003). Construction and interference in learning from multiple
representation. Learning and Instruction, 13(2), 141-156.
Schnotz, W., Kurschner, C. (2008). External and internal representations in the acquisition and
use of knowledge: visualization effects on mental model construction. Instructional
Science, 36(3), 175-190.
Schnotz, W., Lowe, R. (2003). External and internal representations in multimedia learning.
Learning and Instruction, 13, 117-123.
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