Why Multimedia Content Might Actually Diminish Learning

I still remember the first time I popped in the Encarta CD-ROM to my Compaq Presario. It was 1993.

Wasting no time, I went straight for the multimedia content — images, sound bites, video clips and interactive graphs. Instead of reading a couple paragraphs about General John J. Pershing, I could click a button and listen to “Black Jack” personally elaborate on the effectiveness of Marine forces.

It was engaging, addictive and fun. My parents were thrilled because instead of spending my free time playing video games or tormenting my brother, I was browsing an encyclopedia.

The advent of rich media sources like Encarta excited educators, as well.  Most educators assumed that compelling, interactive content would support a more effective learning environment.  Not only could students access different types of media, they could easily explore the relationships between different topics via hyperlinks.  Suddenly, instead of dealing with text-only documents processed in isolated from other content, learners could access a thrilling array of media connected to other relevant resources with the click of a mouse.

Of course, we’ve come a long way since the Encarta-Era (Microsoft discontinued Encarta in 2009). Most of our multimedia content and digital text has moved online. Classrooms are installing interactive whiteboards, giving students laptops to use during class, and teaching technological literacy.  Universities are exploring the use of e-Readers and providing electronic versions of textbooks.

The content itself is higher quality and more accessible. It takes someone with web access about 5 seconds to find a video lecture about bioethics or global warming from a world-renowned expert.  And, for the last 4-5 years, we’ve discovered new ways to allow students to interact with content and their peers using forums, blogs, wikis and other Web 2.0 tools.

The problem is, this interconnected multimedia may not actually strengthen learning.

In his new book The Shallows: What the Internet is Doing to Our Brains, Nicholas Carr cites a collection of studies which suggests the presence of hyperlinks and multimedia in digital documents “strains our cognitive abilities, diminishing our learning and weakening our understanding”.

The theory posits that links and rich media can interrupt the learner from deeply processing the primary document.  This shift in attention, even for a split second, distracts the learner enough to reduce their comprehension of the material.

Carr gives this example from research by Erping Zhu:

She had groups of people read the same piece of writing online, but she varied the number of links included in the passage. She then tested the readers’ comprehension by asking them to write a summary of what they had read and complete a multiple-choice test.  She found that comprehension declined as the number of links increased.

Readers were forced to devote more and more of their attention and brain power to evaluating the links and deciding whether to click on them.  That left less attention and fewer cognitive resources to devote to understanding what they were reading.

Last night, I was reading a book (an old fashion, paper-and-binding book!) with frequent footnotes indicated with the symbol * at the end of the appropriate sentence.  Every time I ran across an asterisk, I had to make a quick decision: Should I skip down to the footnote, or continue reading the main text?  The decision only took a fraction of a second, but there’s no doubt it interrupted my concentration.

Certainly, interruptions are readily available online.  Hyperlinks are everywhere (even in the blog entry you’re reading right now).  Advertisements, social media widgets, and random sidebar content can also vie for your attention.  Is it possible these distractions are diminishing our understanding?

According to Carr, the “cognitive overload” principle also applies to embedded multimedia.  In a 2007 study by Steven Rockwell and Loy Singleton, “researchers recruited more than a hundred volunteers to watch a presentation about the country of Mali.”

Some of the subjects watched a version of the presentation that included only a series of text pages. Another group watched a version that included , along with pages of text, a window in which an audiovisual presentation of related materials was streamed.

After viewing the presentation, the subjects tool a ten-question quiz on the material.  The text-only viewers answered an average of 7.04 of the questions correctly, while the multimedia viewers answered just 5.98 correctly — a significant difference.

There are obviously many educational benefits of multimedia.  It’s difficult to learn about African music without listening to an example of polyrhythm, just as a lesson on refraction virtually requires a diagram or two for clarity.

Still, as our educational culture continues to embrace technology, it’s worth considering the limits of certain strategies.  If students need to learn about Isaac Newton in-depth, it may not be best to start with a digital document full of links and embedded videos.  A small amount of linear-reading might be the most effective.  Some pictures and sample experiments can come later.

The key, says Carr, is to avoid the cognitive overload that results from presenting all the information at one time.  Instead, keep reading focused on one medium at a time.  To increase comprehension, we must cultivate concentration.

This isn’t an easy task.  While the web was new to me in 1993, students today have spend their entire lives negotiating– and generally embracing — online distractions.

Simple text on a page with no links, pictures or interactive chat may be a tough sell, but it just might be one of the best ways to learn.