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Abstract: Spontaneous beat gestures are an integral part of the paralinguistic context during face-to-face conversations. Here we investigated the time course of beat-speech integration in speech perception by measuring ERPs evoked by words pronounced with or without an accompanying beat gesture, while participants watched a spoken discourse. Words accompanied by beats elicited a positive shift in ERPs at an early sensory stage (before 100ms) and at a later time window coinciding with the auditory component P2. The same word tokens produced no ERP differences when participants listened to the discourse without view of the speaker. We conclude that beat gestures are integrated with speech early on in time and modulate sensory/phonological levels of processing. The present results support the possible role of beats as a highlighter, helping the listener to direct the focus of attention to important information and modulate the parsing of the speech stream. [Copyright &y& Elsevier]

Abstract: Converging evidence from behavioral masked priming (Rastle & Davis, 2008), EEG masked priming (Morris, Frank, Grainger, & Holcomb, 2007) and single word MEG (Zweig & Pylkkänen, 2008) experiments has provided robust support for a model of lexical processing which includes an early, automatic, visual word form based stage of morphological parsing that applies to all derivationally affixed words. The mechanisms by which regularly (walked, birds) and irregularly (gave, geese) inflected forms are processed are less well established. We combine the masked priming paradigm with EEG recording to directly compare the ERPs evoked by regularly and irregularly inflected forms. We find equivalent N250 priming effects for both types of morphological complexity, which argues for rapid, form based morphological parsing of all morphologically complex word forms. [Copyright &y& Elsevier]

Abstract: The phonological trace of perceived words starts fading away in short-term memory after a few seconds. Spoken utterances are usually 2–3s long, possibly to allow the listener to parse the words into coherent prosodic phrases while they still have a clear representation. Results from this brain potential study suggest that even during silent reading, words are organized into 2–3s long ‘implicit’ prosodic phrases. Participants read the same sentences word by word at different presentation rates. Clause-final words occurring at multiples of 2–3s from sentence onset yielded increased positivity, irrespective of presentation rate. The effect was interpreted as a closure positive shift (CPS), reflecting insertion of implicit prosodic phrase boundaries every 2–3s. Additionally, in participants with low working memory span, clauses over 3s long produced a negativity, possibly indicating increased working memory load. [Copyright &y& Elsevier]

Abstract: Spatial language descriptions, such as The bottle is over the glass, direct the attention of the hearer to particular aspects of the visual world. This paper asks how they do so, and what brain mechanisms underlie this process. In two experiments employing behavioural and eye tracking methodologies we examined the effects of spatial language on people’s judgements and parsing of a visual scene. The results underscore previous claims regarding the importance of object function in spatial language, but also show how spatial language differentially directs attention during examination of a visual scene. We discuss implications for existing models of spatial language, with associated brain mechanisms. [Copyright &y& Elsevier]

Abstract: Bailey and Ferreira (2003) hypothesized and reported behavioral evidence that disfluencies (filled and silent pauses) undesirably affect sentence processing when they appear before disambiguating verbs in Garden Path (GP) sentences. Disfluencies here cause the parser to “linger” on, and apparently accept as correct, an erroneous parse. Critically, the revision process usually associated with GP-disambiguating verbs does not appear to be triggered. In order to verify this effect, we recorded event-related potentials (ERPs) time-locked to disambiguating verbs in spoken GP sentences from 15 adults. A filled pause, silent pause, or no disfluency appeared before the GP-disambiguating verbs. Principal component analysis (PCA) revealed that fluent GP sentences elicited P600, an ERP index that revision of the initial parse was attempted. Crucially, P600 was attenuated for sentences containing a filled or silent pause before the GP-disambiguating verb. However, PCA detected an N400-like activation for these items, suggesting that listeners accepted the original (erroneous) parse and continued integrating at the verb; a conclusion that is tentative and requires further study. A left anterior positivity was also detected at GP-disambiguating verbs flanked by a filled pause. Discussion focuses on what these preliminary findings tell us about how oral comprehension proceeds when the time-course of sentence processing is disrupted. [Copyright &y& Elsevier]

Psycholinguistic models of sentence parsing are primarily based on reading rather than auditory processing data. Moreover, both prosodic information and its potential orthographic equivalent, i.e., punctuation, have been largely ignored until recently. The unavailability of experimental online methods is one likely reason for this neglect. Here I give an overview of six event-related brain potential (ERP) studies demonstrating that the processing of both prosodic boundaries in natural speech and commas during silent reading can determine syntax parsing immediately. In ERPs, speech boundaries and commas reliably elicit a similar online brain response, termed the Closure Positive Shift (CPS). This finding points to a common mechanism, suggesting that commas serve as visual triggers for covert phonological phrasing. Alternative CPS accounts are tested and the relationship between the CPS and other ERP components, including the P600/SPS, is addressed. [Copyright &y& Elsevier]

This article is concerned with the role of prosody in discourse. Three experiments explored the relationship between inspiration, declination, and syntactic boundaries in normal and RHD participants. Fundamental frequency and intensity were measured at the beginning and end of breath units excised from conversational samples. The results revealed evidence of declination of intensity in all samples measured. However, resetting of fundamental frequency was observed only in the samples of normal participants and then only when a breath coincided with the beginning of a sentence. The results suggest that resetting and declination play separate roles in discourse parsing. [Copyright &y& Elsevier]