by French, Ekstrom & Price (1963). The test requires subject to visualize the array of holes that result from a
simple process. A paper is folded a certain number of folds, a hole is made through the folds then the paper is
unfolded. Students are asked to select the image of the unfolded paper that shows the resulting arrangement and
results are discriminated along a median split as high versus low visualization abilities. Students of both groups
where then split into two groups and taught how to solve syllogisms either through Euler’s circles, which is
graphical, or through natural deduction, which is serial.
Following this, students were given a test with 8 syllogisms each, selected to cover a range of difficulties. They
were instructed to solve them in one of the two ways according to the way they were taught. Results showed
that those who scored high on the PFT test made fewer errors when taught to solve them using Euler’s circles
than their serialist counterparts, who scored low on the PFT test when given the same teaching method. Oddly
enough, this influence only seemed to take place in the final stage or in the translation of the results from the
graphical modality into sentential form. The most important result is that most subjects would either perform
better when taught verbally or when taught through diagrams according to their abilities or preferences.
Additionally, those with visualization abilities seem to need a stage of “translation” from one modality to the
other. In order to draw the student closer to the cognitive operation, the medium that forms the cognitive
environment should not be intimidating. Additionally, the amount of freedom designated to the student plays the
main role of the entire process. The only problem appears when the system somehow hinders the learning
ability, and the results show a channeling of the student to think through one of the two methods. This leads to
one main conclusion. The ideal way of describing a process to students must allow for possible individual
diffe rences.
2. Verbal/Pictorial vs. Animated
Now that both methods of representation seem necessary, a question arises as to whether one can subsume the
other and present itself as the “ideal” method of teaching the behavior of processes. In short, is animation the
“ideal” way? Well, evidently from research, there seems to be a serious difficulty in getting clear-cut results to
say that animation is more effective than verbal/pictorial representation or vice versa.
Pane, Corbett, and John (1996) ran a detailed study to assess the effects of dynamics representation in a
computer-based system that teaches developmental biology. They compared animation to a textual description
that is enriched with carefully selected still images. They found no difference in student performance when
declarative questions are given. Another study (Lawrence, Badre & Stasko,1994) showed that with respect to
teaching algorithms, “active laboratory” sessions seemed to result in better student performances. During these
sessions students created their own algorithms and saw them animated. They performed better in “procedural
questions” as compared to students who were exposed to animations of previously selected examples.
Two other experiments showed that animations might aid students in procedural knowledge by allowing them to
“predict” the next step in an algorithm’s behavior. However, similar results were found when students were
asked to predict algorithm behavior from static diagrams (Byrne, Catrambone & Stasko, 1999). Then what role
does animation play?
“When the perceptual system cannot directly perceive change over time, it will seek out implicit evidence of
change.” (Freyd, 1987)
Perhaps these findings are not as surprising as they may seem at first sight, if we presume dynamic mental
representations. Freyd (1987) showed through several experiments the existence of a memory distortion that
represents a shift forward to the next expected state when even one image is shown. One of her experiments
involved two static images of a man jumping off a wall. A subject is shown one image first. The subject would
then be shown another image and asked whether they are the same. For example, if in the first image, the man is
in the air, then subjects would readily identify that the image of the man standing on the wall is not the same.
On the other hand, they would take longer to identify the difference if the order of the images was reversed.
This implies that subjects “expected” the second image to follow the first one temporally. This order was
maintained in the experiments described above. In fact, the first study on developmental biology (1996) replaces
an animation with a sequence of four images that show different screen shots of stages in the animation. These
images, according to dynamic representation are no different from exposure to the animation itself because a
dynamic cognitive representation would fill in the gaps.
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