| |
Abstract:
Recent behavioral studies suggest that the quality of the
acoustic signal determines the extent to which semantic context
influences the comprehension of spoken words. Reaction times (RTs)
to word targets are typically faster when targets are congruent
with the semantic context than when they are incongruent with the
context. However, when the semantic context is acoustically
distorted, the RT difference between congruent and incongruent
targets is significantly reduced (Utman & Bates, 1998). The
present study examined event-related potentials (ERPs) to spoken
words presented in a sentence context. ERPs were recorded from 16
electrode sites in response to a target word that occurred in
sentence-medial position in each experimental trial. This target
was either congruent with the context, or appeared in one of two
violation conditions: semantic, in which the target was
incompatible with the semantic context, or syntactic, in which the
order of the target and the following word was reversed. The target
was acoustically intact in all conditions. The semantic context was
either acoustically intact or low-pass filtered at 1 kHz.
Preliminary results suggest that acoustic distortion modulates both
semantic and syntactic influences on neural responses to single
words in a sentence context.
|
