Verbal vs. Visual : One at a time please

Researchers at the University of New South Wales indicate that the human brain retains more information if presented verbally, or in written form, but both at once reduces retention.  The obvious application of this result is the widespread use of Powerpoint.

However, it is noted that diagrams or images are still useful, it's just the practice of reading point form slides which is detrimental.  I'd thus note that what they've really found is that bad presentation slides hinder retention, not slides in general. 

via Slashdot