Recent advances in technology have provided a wide variety of possibilities for incorporating animation in computer-based learning environments. In a very general sense, the term ‘animation’ can refer to any display element that changes its attributes over time. Taken this broadly, examples such as words that fly across the screen or objects that vibrate, blink, or change their color would be regarded as animations (Wright, Milroy, & Lickorish, 1999). In this chapter, we use the term in a more restricted sense. We define ‘animation’ as a pictorial display that changes its structure or other properties over time and which triggers the perception of a continuous change. Our definition includes examples of dynamic visualization such as pictorial displays that present objects continuously from different perspectives, show the assembly of a complex object from its parts, present the functioning of a technical device such as a bicycle pump, display the dynamic behavior of a meteorological system, or model the co-variation of variables in a graph (Bodemer, Ploetzner, Feuerlein, & Spada, 2004; Hegarty, Narayanan, & Freitas, 2002; Lowe, 2004; Mayer, 2001, 2005; Mayer & Moreno, 2002; Schwan & Riempp, 2004).
Although the use of animation has been enabled and stimulated by technology, our definition excludes technical considerations such as the number of frames per second and whether or not the pictorial display is computer generated. However, our definition does include video (cf. Baek & Layne, 1988; Betrancourt & Tversky, 2000). Steven Spielberg’s film "Jurassic Park" demonstrated that viewers cannot distinguish sequences generated by computer from those filmed in a conventional studio. Although these differences in how sequences were generated may be important from a technical perspective, they are obviously of no psychological relevance to the viewer.
On the one hand, animations are frequently considered as inherently superior to static pictures. Whereas static pictures display only visuospatial information, animations display temporal information as well. Accordingly, animations can be considered as more informative, more natural or more ‘authentic’ than the corresponding static pictures. Thus, it is very tempting to assume that learning from animation will be more effective than learning from static pictures. On the other hand, learning from animation can also be seen as more demanding because more information has to be processed and this imposes a higher cognitive load on the learner’s working memory (Sweller, van Merriënboer, & Paas, 1998).
These two views encapsulate the prevailing tendency to emphasize differences between animated and static graphics rather than to consider their commonalities. From a technological perspective, there may well be clear differences between static and animated pictures with regard to the physical nature of the representation. However, from a psychological perspective, they are fundamentally linked in terms of the human information processing capacities that operate upon them both during learning. Our evolutionary history has given us a perceptual and cognitive system that is well equipped to cope with world in which change is part of the normal condition. The highly dynamic environment in which we live usually includes both temporally stable and temporally changing components. In our everyday lives, we do not continually compartmentalize our environment into static and dynamic parts. Rather, we deal with these components in an integrated and flexible manner as we continually construct a coherent functional mental representation of the world around us. Even when we move through a static environment, our visual field is continuously changing. The flux of our everyday experience is thus a seamless blend of changing and unchanging stimuli without fixed boundaries between static and dynamic components. On this basis, it seems difficult to justify a sharp distinction between learning from animated and learning from static pictures, and there appears to be little reason to assume that animations are necessarily easier or more demanding than static pictures.
In this chapter, we will therefore argue for a more unified approach to dealing with animations and static pictures. The basis for this argument is that animations and static pictures are not fundamentally different from a psychological point of view because animated and static pictures are processed by the same perceptual and cognitive system. Given that this system has evolved by interacting with a complex environment containing an ongoing blending of both dynamic and stable stimuli, the same set of basic perceptual and cognitive principles should underlie learning from both types of representation. It follows that the principles for using animation effectively are not fundamentally different from those for using static pictures and that the former can be considered as an extension of the latter. With regard to educational practice, we suggest that designers and developers of learning resources should not consider animation as something totally different in a qualitative sense and that therefore requires totally new design principles. Rather, they could learn from our history’s rich legacy of visual communication in order to understand and apply underlying principles that are common to static and animated graphics. With regard to educational theory, we suggest that researchers should not ‘re-invent the wheel’ by considering learning from animation as a fundamentally different branch of scientific analysis. Rather, they should view this topic as closely related to other research on visual communication.