Investigating the Time Course of Spoken Word Recognition: Electrophysiological Evidence for the Influences of Phonological Similarity

Abstract

Behavioral and modeling evidence suggests that words compete for recognition during auditory word identification, and that phonological similarity is a driving factor in this competition. The present study used event-related potentials [ERPs] to examine the temporal dynamics of different types of phonological competition (i.e., cohort and rhyme). ERPs were recorded during a novel picture-word matching task, where a target picture was followed by an auditory word that either matched the target (CONE-cone), or mismatched in one of three ways: rhyme (CONE-bone), cohort (CONE-comb), and unrelated (CONE-fox). Rhymes and cohorts differentially modulated two distinct ERP components, the Phonological Mismatch Negativity [PMN] and the N400, revealing the influences of pre-lexical and lexical processing components in speech recognition. Cohort mismatches resulted in late increased negativity in the N400, reflecting disambiguation of the later point of miscue and the combined influences of top-down expectations and misleading bottom-up phonological information on processing. In contrast, we observed a reduction in the N400 for rhyme mismatches, reflecting lexical activation of rhyme competitors. Moreover, the observed rhyme effects suggest that there is interaction between phoneme-level and lexical-level information in the recognition of spoken words. The results support the theory that both levels of information are engaged in parallel during auditory word recognition in a way that permits both bottom-up and top-down competition effects. Keywords Perception; Auditory processing; Event related potentialsIn understanding spoken language listeners need to both perceive incoming auditory information and access a semantic representation of that input. Although speech is understood quite rapidly and effortlessly, the cognitive processing involved in spoken word recognition is not trivial. In order to recognize what is being said, acoustic information must be translated into a phonological code, segmented into discrete words, and integrated with both the immediate context and prior knowledge such as word familiarity and contextual CIHR Author ManuscriptCIHR Author Manuscript CIHR Author Manuscript cues. Consistent with this, studies have revealed a range of factors that influence auditory word recognition (Luce & Pisoni, 1998;Norris, McQueen, & Cutler, 2000;Frauenfelder & Tyler, 1987;McClelland & Elman, 1986). These can be coarsely divided into two categories: those revealing the influence of 'pre-lexical' cues related to acoustic and phonological features, and those indexing the role of 'lexical' knowledge that denotes lexical-level influences such as frequency. There is significant ongoing discussion about exactly how auditory words are recognized, focusing on how and when these different types of information are accessed during the time course of processing, and furthermore, the extent to which these interact.Evidence suggests that spoken words are processed as speech unfolds, and that phonologically similar items ...

Tracking the Time Course of Word‐Frequency Effects in Auditory Word Recognition With Event‐Related Potentials

“…Four time windows were selected around the peak amplitude of each component after visual inspection: 90-110 ms (N100), 2 250-330 ms (PMN), 330-400 ms (P350), and 400-500 ms (N400). A late time window between 550 and 650 ms after the word onset was also used to analyze later effects on the N400 component (see for a similar approach, Desroches et al, 2009). …”

“…In a recent study, Desroches et al (2009) examined the impact of different types of phonological competitors which were supposed to be activated during word recognition. More particularly, they used a picture-word matching task in which participants saw a picture followed by an auditory probe word and had to judge whether the picture and the probe were the same.…”

Predictive Top-Down Integration of Prior Knowledge during Speech Perception

“…For late latencies when there were no clear peaks, two broad windows were defined (270 -420 and 450 -700 ms) that correspond approximately to the early and late portions of the N400 component (cf. Desroches et al, 2009). After time averaging, F tests were performed across sensor space while controlling the FWE rate using random field theory (Kilner and Friston, 2010).…”

Does Semantic Context Benefit Speech Understanding through “Top–Down” Processes? Evidence from Time-resolved Sparse fMRI

“…This is apparent in EEG studies in which phonological mismatch responses are elicited when spoken words are different from what the listener expected on the basis of a preceding sentence or picture (Desroches, Newman, & Joanisse, 2009;Connolly & Phillips, 1994). A visual EEG study provides strong evidence for lexical prediction (DeLong, 2005) because readers registered a mismatch response to the indefinite article "an" when a consonant-initial word (hence, "a") is expected (e.g., "the day was breezy so the boy went out to fly a kite" vs. "…fly an airplane"; DeLong, Urbach, & Kutas, 2005).…”