In 2008, Ritzhaupt, Gomes, and Barron
studied the relationship between verbal
redundancy and time-compression in audioenhanced
multimedia learning materials. In
the study, 183 undergraduates were randomly
assigned to one of three audio-enhanced
multimedia presentations that were recorded at
three speeds (1.0, 1.4, and 1.8). The dependent
measures in the study were comprehension and
satisfaction. Time-compression was treated as a
between-subjects effect, verbal redundancy was
treated as a within-subjects effect. The results show
no significant difference on performance across
treatments (suggesting that one can accelerate the
speed of narration without adversely influencing
comprehension) and a significant difference
on satisfaction in favor of 1.4 times the normal
audio speed. The results also indicate statistical
differences in favor of verbal redundancy, in