Just an off the cuff post during lunch: There is an article republished on Outlaw called Official: Powerpoint bad for brains, which I tend to agree with, but I suspect their analysis of the cause may be flawed.
They say that:
Humans just don’t like absorbing information verbally and visually at the same time – one or the other is fine but not both simultaneously.
Researchers at the University of New South Wales in Australia found the brain is limited in the amount of information it can absorb – and presenting the same information in visual and verbal form – like reading from a typical Powerpoint slide – overloads this part of memory and makes absorbing information more difficult.
That goes against a lot of previous research on multimedia and learning (e.g. Multimedia Learning), where presenting information in more than one modality (e.g. visually and verbally) increases the uptake of information. Like the proverb:
Tell me, I’ll forget.
Show me, I’ll remember.
Involve me, I’ll understand.
I would bet that the effect they found was because people were completely bored by the presentation, and lost interest in one or both modalities. The presentation did not keep their attention, as people (especially since MTV, the internet and other modern entertainment) generally are used to quite a high level of ‘stimulation’. (After all, they tested students…)
Personally (i.e. anecdotally), I’ve found listening to podcasts whilst reading a transcript increases my interest and uptake of that information. Don’t get me wrong, a decent presentation should involve very little text, but not because people get overloaded. Whilst checking my assumptions, I found what looks like a useful summary of what to do for presentations based on research findings.
The original article is worth a read (Visualisation and Instructional Design, 236k untagged PDF) if you are inclined towards psychology research articles.
This was said better on Presentation Zen.