Week 3: Cognitive load in hypertext reading – Summary

This paper by Diana DeStefano & Jo-Anne LeFevre explores the impact of hypertext reading on learning. The use of hypertext has changed the way a reader constructs information in his mind by navigating through related topics across hyperlinks. The speed of learning is affected by the way the subject is organized, presented and illustrated with the aid of hypertext, graphics and multimedia constructs. The growth of hypertext in general has altered the conventional way of creating educational material by the authors and the eventual learning by the readers. As a result, it’s important to understand the consequences of using hypertext in learning and education. The authors reviewed the results of 38 relevant studies conducted in a period of 14 years (1990-2004) and outlined their findings in this paper.

Cognitive load is defined as the mental effort that a reader employs while reading to gather information and to summarize them into a concrete learning experience. The authors of the paper hypothesizes that the presence of hypertext increases cognitive load on the reader in general and adversely impacts the speed of learning. Some of the studies that strengthen the hypothesis are as follows:

·         Plass, Chun, Mayer and Leutner (2003) found that hypertext with visual annotations impair reading performances substantially. They were examining the impact of both visual and verbal annotations on foreign language texts and found that the visual content often distracted readers as it interrupted their natural pace and increased cognitive load.

·         Zhu (1999), Jacko & Salvendy (1996), Landauer & Nachbar (1985) and Parush, Shwartz, Shtub & Chandra (2005) in independent studies confirmed that the increase in the number of hypertext links increases the difficulty of reading and degrades comprehension performance.

·         McDonald and Stevenson (1996), van Nimwegen, Pouw & van Oostendorp (1999) found that the navigation performance of a reader declines with increasing number of hypertext links. Navigation performance is defined as the speed at which a reader can find answers in a given text after an initial browsing period.

·         Budd, Whitney & Turley (1995) and Lee & Tedder (2003) found that readers with low working memory (WM) spans are more disadvantaged while reading hypertext as compared to people with high WM spans. People with low WM spans have less cognitive capacity in terms of remembering what they immediately read and it’s easier for them to understand structured text with clear topics than hypertexts with minimal contextual information.

·         Lodevijks (1982), Oberauer et all (2000), Witkin, Moore, Goodenough & Cox (1997) and McNamara, Kintsch, Songer & Kintsch (1996) concluded that students with low reasoning ability or less prior knowledge benefits more from logically sequenced texts while students with better skills on the above benefits when they can structure their own reading on hypertext based content.

·         Miall & Dobson (2001) and Barab et al (1999) examined and found that readers could be confused and could miss important material while reading hypertext based literary contents.

There are a few studies which explored similar areas but either didn’t agree with the hypothesis or were inconclusive. Some of them are listed here:

·         Wenger and Payne (1996) didn’t find any notable difference in reading performance for hypertext versus the linear text. Their experiment on the impact of spatial and verbal loads while reading hypertext failed to produce consistent result across different text samples.

·         Lin (2003) and Mohageg (1992) didn’t find any direct degradation in navigation performance with increased number of links. This contradicts with other studies that that concluded the opposite. However, there were no indications that the increase in links improves performance. Also most of the related studies concluded that semantic links hurts performance as it interferes with the hierarchical nature of texts.

·         Baron, Taguesutcliffe, Kinnucan & Carey (1996) and Campbell & Maglio (1999) found that the use of techniques like providing labels or creating descriptors to define a hyperlink actually enhances learning. Both of them improved the accuracy of locating information and raised navigation performance.

In summary, the majority of studies tend to confirm that students with lower reading abilities find it harder to comprehend while reading hypertext based contents while the ones with higher reading abilities adapt better as they can use the flexibility of the hypertext to plan their own learning. This is more or less intuitive as the potential benefits of hypertexts can often be negated by the increased cognitive load in processing the same information through hypertexts, as it tends to increase the difficulty of reading.

Finally, the paper cites a few limitations of the studies and calls for future studies to analyze specific learner characteristics (e.g. prior knowledge, working memory capacity and ability to impose structure) to design their experiments and author their findings.