This study investigated the influence of top-down and bottom-up
information on speech perception in complex listening
environments. Specifically, the effects of listening to
different types of processed speech were examined on
intelligibility and on simultaneous visual-motor performance.
The goal was to extend the generalizability of results in speech
perception to environments outside of the laboratory. The effect
of bottom-up information was evaluated with natural, cell phone
and synthetic speech. The effect of simultaneous tasks was
evaluated with concurrent visual-motor and memory tasks. Earlier
works on the perception of speech during simultaneous visual-
motor tasks have shown inconsistent results (Choi, 2004; Strayer
& Johnston, 2001). In the present experiments, two dual-task
paradigms were constructed in order to mimic non-laboratory
listening environments. In the first two experiments, an
auditory word repetition task was the primary task and a visual-
motor task was the secondary task. Participants w