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PURPOSE: According to most models of spoken word recognition, listeners probabilistically activate a set of lexical candidates, which is incrementally updated as the speech signal unfolds. Speech carries segmental (speech sound) as well as suprasegmental (prosodic) information. The role of the latter in spoken word recognition is less clear. We investigated how suprasegments (tone and voice quality) in three North Germanic language varieties affected lexical access by scrutinizing temporally fine-grained neurophysiological effects of lexical uncertainty and information gain.METHOD: Three event-related potential (ERP) studies were reanalyzed. In all varieties investigated, suprasegments are associated with specific word endings. Swedish has two lexical "word accents" realized as pitch falls with different timings across dialects. In Danish, the distinction is in voice quality. We combined pronunciation lexica and frequency lists to calculate estimates of lexical uncertainty about an unfolding word and information gain upon hearing a suprasegmental cue and the segment upon which it manifests. We used single-trial mixed-effects regression models run every 4 ms.RESULTS: Only lexical uncertainty showed solid results: a frontal effect at 150-400 ms after suprasegmental cue onset and a later posterior effect after 200 ms. While a model including only segmental information mostly performed better, it was outperformed by the suprasegmental model at 200-330 ms at frontal sites.CONCLUSIONS: The study points to suprasegmental cues contributing to lexical access over and beyond segments after around 200 ms in the North Germanic varieties investigated. Furthermore, the findings indicate that a previously reported "pre-activation negativity" predominantly reflects forward-looking processing.SUPPLEMENTAL MATERIAL: https://doi.org/10.23641/asha.25016486.

We propose that a recently discovered event-related potential (ERP) component—the pre-activation negativity (PrAN)—indexes the predictive strength of phonological cues, including segments, word tones, and sentence-level tones. Specifically, we argue that PrAN is a reflection of the brain’s anticipation of upcoming speech (segments, morphemes, words, and syntactic structures). Findings from a long series of neurolinguistic studies indicate that the effect can be divided into two time windows with different possible brain sources. Between 136 and 200 ms from stimulus onset, it indexes activity mainly in the primary and secondary auditory cortices, reflecting disinhibition of neurons sensitive to the expected acoustic signal, as indicated by the brain regions’ response to predictive certainty rather than sound salience. After ~200 ms, PrAN is related to activity in Broca’s area, possibly reflecting inhibition of irrelevant segments, morphemes, words, and syntactic structures.

The pre-activation negativity (PrAN) is an event-related potential (ERP) component indexing how constraining phonological cues are. It has an early phase (136-200 ms), with sources in the left auditory cortices, and a late phase (200 ms onwards), with sources in Broca’s area. The PrAN has been found for segmental and prosodic cues increasing the certainty about upcoming words, morphemes, grammatical structures, or lexicality. The phonological cues investigated have been Central Swedish, South Swedish, Danish, and English segmental phonemes, Central and South Swedish lexical tone accents, Danish stød, and Central Swedish boundary tones and left-edge boundary tones/initiality accents.

Swedish lexical word accents have been repeatedly said to have a lowfunctional load. Even so, the language has kept these tones ever sincethey emerged probably over a thousand years ago. This article proposesthat the primary function of word accents is for listeners to be ableto predict upcoming morphological structures and narrow down thelexical competition rather than being lexically distinctive. Psycho- andneurophysiological evidence for the predictive function of word accents isdiscussed. A novel analysis displays that word accents have a facilitativerole in word processing. Specifically, a correlation is revealed betweenhow much incorrect word accents hinder listeners’ processing and howmuch they reduce response times when correct. Finally, a dual-route modelof the predictive use of word accents with distinct neural substrates isput forth.