The Sense of Sounds: Brain Responses to Phonotactic Frequency, Phonological Grammar and Lexical Meaning.

Susana Silva,Barbara Leone Fernandez,Kai Alter,Sónia Frota,Marina Vigário,Rita Jerónimo

doi:10.3389/fpsyg.2019.00681

Abstract

Two outstanding questions in spoken-language comprehension concern (1) the interplay of phonological grammar (legal vs. illegal sound sequences), phonotactic frequency (high- vs. low-frequency sound sequences) and lexicality (words vs. other sound sequences) in a meaningful context, and (2) how the properties of phonological sequences determine their inclusion or exclusion from lexical-semantic processing. In the present study, we used a picture-sound priming paradigm to examine the ERP responses of adult listeners to grammatically illegal sound sequences, to grammatically legal sound sequences (pseudowords) with low- vs. high-frequency, and to real words that were either congruent or incongruent to the picture context. Results showed less negative N1-P2 responses for illegal sequences and low-frequency pseudowords (with differences in topography), but not high-frequency ones. Low-frequency pseudowords also showed an increased P3 component. However, just like illegal sequences, neither low- nor high-frequency pseudowords differed from congruent words in the N400. Thus, phonotactic frequency had an impact before, but not during lexical-semantic processing. Our results also suggest that phonological grammar, phonotactic frequency and lexicality may follow each other in this order during word processing.

Highlights

Mapping sound into meaning, i.e., semantic processing, is the ultimate goal in spoken language comprehension
Whether illegal sequences and pseudowords are equivalent in early processing stages, and whether an association between illegal sequences and pseudowords in early processing is modulated by the phonotactic frequency of pseudowords
We addressed two questions: (1) Whether illegal sequences and pseudowords are equivalent in early processing stages, and a possible association between illegal sequences and pseudowords in early processing is modulated by the phonotactic frequency of pseudowords; (2) Whether high- and low-frequency pseudowords are both included in or excluded from lexical-semantic processing

Summary

Introduction

I.e., semantic processing, is the ultimate goal in spoken language comprehension. The N400 for words may be experimentally elicited in sentence context, as in the previous example (e.g., Van den Brink and Hagoort, 2004; Laszlo and Federmeier, 2009; Brunellière and Soto-Faraco, 2015; Payne et al, 2015), or by priming techniques (e.g., Holcomb and Neville, 1990; Desroches et al, 2009; Robson et al, 2017; Wiese et al, 2017; Haebig et al, 2018) These techniques use a prime word or a prime picture followed by the target word, with prime-target pairs being either semantically congruent or incongruent. By examining ERP responses to the sound-picture pairings, we investigated the interplay of phonological grammar (legal vs. illegal sound sequences), phonotactic frequency (high- vs. lowfrequency sound sequences) and lexicality (words vs. other sound sequences) on word processing

Methods

Results

Conclusion