Hemispheric differences in indexical specificity effects in spoken word recognition.

Abstract

Variability in talker identity, one type of indexical variation, has demonstrable effects on the speed and accuracy of spoken word recognition. Furthermore, neuropsychological evidence suggests that indexical and linguistic information may be represented and processed differently in the 2 cerebral hemispheres, and is consistent with findings from the visual domain. For example, in visual word recognition, changes in font affect processing differently depending on which hemisphere initially processes the input. The present study examined whether hemispheric differences exist in spoken language as well. In 4 long-term repetition-priming experiments, the authors examined responses to stimuli that were primed by stimuli that matched or mismatched in talker identity. The results demonstrate that indexical variability can affect participants' perception of spoken words differently in the 2 hemispheres.

Hemispheric differences in specificity effects in talker identification

“…The results of Experiment 1 on talker identification are consistent with predictions based on our previous results obtained in spoken word (González & McLennan, 2007) and environmental sound (González & McLennan, 2009) would appear when the spoken sentences were presented to the left ear (RH), relative to when the spoken sentences were presented to the right ear (LH).…”

“…In the auditory domain, we recently found the same asymmetric pattern of specificity effects in the recognition of both spoken words (González & McLennan, 2007) and environmental sounds (González & McLennan, 2009). In the first study, we obtained hemispheric differences in talker specificity effects in spoken word recognition: The RH was more sensitive than the LH to surface information associated with talker identity during lexical perception.…”

“…Pink noise has a spectral frequency of 1/f and is found mostly in nature. It was chosen (as in González & McLennan, 2007) because its spectral level decreases with increasing frequency, as occurs in speech signals, and thus serves as an effective voice masker (and is also less annoying than white noise).…”

Hemispheric Differences in the Recognition of Environmental Sounds

“…Presenting infor mation to the two hemispheres simultaneously would be ex pected to increase competition between the hemispheres and to increase the likelihood of observing hemispheric asymmetries (Fecteau, Enns, & Kingstone, 2000;González & McLennan, 2007;Kimura, 1961).…”

“…The design was similar to that of other long term repetition priming experiments (González & McLennan, 2007;McLennan & Luce, 2005;McLennan, Luce, & Charles Luce, 2003). Par ticipants were seated in front of a computer and listened to stimuli presented in two blocks.…”