No place for /h/: an ERP investigation of English fricative place features

Abstract

The representational format of speech units in long-term memory is a topic of debate. We present novel event-related brain potential evidence from the Mismatch Negativity (MMN) paradigm that is compatible with abstract, non-redundant feature-based models like the Featurally Underspecified Lexicon (FUL). First, we show that the fricatives /s/ and /f/ display an asymmetric pattern of MMN responses, which is predicted if /f/ has a fully specified place of articulation ([Labial]) but /s/ does not ([Coronal], which is lexically underspecified). Second, we show that when /s/ and /h/ are contrasted, no such asymmetric MMN pattern occurs. The lack of asymmetry suggests both that (i) oral and laryngeal articulators are represented distinctly and that (ii) /h/ has no oral place of articulation in long-term memory. The lack of asymmetry between /s/ and /h/ is also in-line with traditional feature-geometric models of lexical representations.

Keywords: Featurally Underspecified Lexicon; MMN; Phonological features; RP; underspecification.

Figure 1.

Conditions and predictions. The difference waves for the FS blocks (top) predict an asymmetric MMN pattern. The MMN pattern produced by difference waves for the HS blocks will be used to determine the featural representation of /h/.

Figure 2.

(a) Cluster analysis based on MFCC of the stimuli. (b) Cluster analysis based on delta coefficients of the stimuli. Both cluster analyses used the Neighbor-Joining Tree algorithm (Mielke, ; Saito and Nei, 1987). (c) Stimuli projected onto the first two dimensions of the compromise between the two distance matrices (Abdi et al., 2012). The first dimension clearly separates the segments [s], [f] and [h] along its axis in three small clusters, whereas the second dimension further separates the [s] and [h] clusters from the [f] cluster.

Figure 3.

Difference waves (at Fz) consisting of the average of deviant trials for a given segment minus the average of standard trials for the same segment; topographic maps and bar plot of MMN mean amplitude during 173–248 ms time window. Both error bars on bar plot and width of ribbon represent ±2 standard errors.

Figure 4.

Feature geometric representation of oral and laryngeal articulators. The oral and laryngeal articulators may be represented distinctly, as in notes on a feature geometry tree.