One thing I have often wondered about when considering videos/animations/audio files is that unlike something written on a piece of paper, the information in multimedia presentation moves on quite quickly. With paper, one can get a sense of the whole, see the sequence, refer back quickly to what went before. With audio or video, information, and often quite complex information, is presented at the pace of the speaker, and it takes a bit of effort to go back and review a segment (i.e. not a glance of an eye). Therefore, for technical topics like chemistry, is there an issue with using multimedia generally?
This idea was discussed in a recent paper by John Sweller and others.* They cite a raft of studies which show that animations do not have any beneficial impact on learning. In this study, they conducted two experiments. The context is that with animations, learners need to simultaneously remember what was just presented along with what is being presented. However, depending on the pace, previous information may be forgotten, and cannot be recalled as easily as static graphics on a piece of paper. Segmentation and user control has previously been shown to aid novice learners. Effective segmentation means that the amount of any information in any segment is within working memory limits.
The first experiment showed children an origami task – it was important that the task included technical elements. Obviously, watching TV includes long sections of text that can be easily processed. The difficulty is the inclusion of technical elements. The task involved 24 steps. Students were shown either video or a series of static images, either in short segments or a continuous presentation. The post-test scores showed students who watched animations scored better than those who had static images, but only if the animation was in short sections.
The second experiment considered length of verbal statements. Students were given instruction on how to read a temperature-time graph, and given five worked examples. The information was presented to the four groups as (1): longer audio text; (2) longer visual text; (3) shorter audio text; (4) shorter visual text. This information was presented in a 330 second presentation, but the amount of explanatory text on the slides differed (long vs short visual text) and in the case of audio only, the explanatory text on the slides was removed and presented as long or short audio segments. After instruction, students were given a post-test. These scores show that the longer visual text was preferable (reverse modality effect). The shorter audio was preferable to the longer audio. These results demonstrate that short spoken statements can be easily held in the auditory working memory, allowing visual memory to process the graphics on the slide. Written information crowds the visual working memory space, reducing capacity to process. However, long auditory information can be difficult to process.
In terms of designing e-resources, these experiments appear to suggest that animations have a beneficial impact on learning, but should be presented in short segments to novice learners, to allow time to process. Audio commentary is beneficial, but again short segments are more useful.
With regards to animations, I think interactivity is important, as it allows the user to click through at their own pace rather than just watching passively. Perhaps table of contents listing slides might help with audio statements, leaving it possible for users to click back on a slide they wish to revisit. But it is a pertinent reminder not to go off on long audio meanders as is our wont.
*A Wong, W Leahy, N Marcus, J Sweller, Cognitive Load Theory, the transient information effect and e-learning, Learning and Instruction, 2012, 22, 449-475.