Neuronal spoken word recognition: The time course of processing variation in the speech signal

Abstract

Recent neurobiological studies revealed evidence for lexical representations that are not specified for the coronal place of articulation (PLACE; Friedrich, Eulitz, & Lahiri, 2006; Friedrich, Lahiri, & Eulitz, 2008). Here we tested when these types of underspecified representations influence neuronal speech recognition. In a unimodal auditory–auditory word fragment priming experiment target words either had initial coronal PLACE (e.g., tiger) or had initial noncoronal PLACE (e.g., pony). Prime-target pairs were either identical (e.g., ti-tiger, po-pony), differed in initial PLACE (e.g., pi-tiger, to-pony), or were unrelated. Event-related Potentials for identical and related targets started to differ from unrelated targets at 100 ms, indicating early perceptual processing. Different effects for coronal vs. noncoronal variation were observed starting at 200 ms. Results are related to recent neurocognitive research on compensation for assimilation of PLACE (e.g., rainbow realised as *raimbow). A time line of processing PLACE variation at multiple stages is proposed and parallel processing of specified and underspecified representations at the lexical level is discussed.

Keywords:

• Spoken language comprehension
• Lexical representations and processes
• Underspecification
• Event-related potentials

ACKNOWLEDGEMENTS

The work was supported by a grant of the German Research Foundation (Deutsche Forschungsgemeinschaft, DFG, FR 2591/1-1) and a Starting Independent Investigators Grant of the European Research Council (ERC, 209656 Neurodevelopment) awarded to CF. We are grateful to Katja Apel and Sirkka Klöpper for help in data acquisition, and to Margriet Groen for comments on a former version of this manuscript.

Notes

¹Note that the central negativity elicited in word fragment priming is different from the earlier mentioned pseudoword negativity. In word fragment priming the prime (fragment) leads to a phonological priming of the target word and therefore elicits a central negativity; whereas only a pseudoword as a target is needed to elicit a pseudoword negativity. This difference in design (word-fragment priming to test lexical access during word processing; pseudoword presentation to test semantic integration during or after word processing) leads to functionally different ERP-effects around 400ms.