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The present study extends neuro-imaging into conversation through studying dialogue comprehension. Conversation entails rapid responses, with negative semiotics for delay. We explored how expectations about the valence of the forthcoming response develop during the silence before the response and whether negative responses have mainly cognitive or social-emotional consequences. EEG-participants listened to questions from a spontaneous spoken corpus, cross-spliced with short/long gaps and “yes”/“no” responses. Preceding contexts biased listeners to expect the eventual response, which was hypothesised to translate to expectations for a shorter or longer gap. “No” responses showed a trend towards an early positivity, suggesting socio-emotional consequences. Within the long gap, expecting a “yes” response led to an earlier negativity, as well as a trend towards stronger theta-oscillations, after 300 milliseconds. This suggests that listeners anticipate/predict “yes” responses to come earlier than “no” responses, showing strong sensitivities to timing, which presumably promote hastening the pace of verbal interaction.

Conversation is generally characterized by smooth transitions between turns, with only very short gaps. This entails that responders often begin planning their response before the ongoing turn is finished. However, controversy exists about whether they start planning as early as they can, to make sure they respond on time, or as late as possible, to minimize the overlap between comprehension and production planning. Two earlier EEG studies have found neural correlates of response planning (positive ERP and alpha decrease) as soon as listeners could start planning their response, already midway through the current turn. However, in these studies, the questions asked were highly controlled with respect to the position where planning could start (e.g., very early) and required short and easy responses. The present study measured participants’ EEG while an experimenter interviewed them in a spontaneous interaction. Coding the questions in the interviews showed that, under these natural circumstances, listeners can, in principle, start planning a response relatively early, on average after only about one third of the question has passed. Furthermore, ERP results showed a large positivity, interpreted before as an early neural signature of response planning, starting about half a second after the start of the word that allowed listeners to start planning a response. A second neural signature of response planning, an alpha decrease, was not replicated as reliably. In conclusion, listeners appear to start planning their response early during the ongoing turn, also under natural circumstances, presumably in order to keep the gap between turns short and respond on time. These results have several important implications for turn-taking theories, which need to explain how interlocutors deal with the overlap between comprehension and production, how they manage to come in on time, and the sources that lead to variability between conversationalists in the start of planning.

Rapid response latencies in conversation suggest that responders start planning before the ongoing turn is finished. Indeed, an earlier EEG study suggests that listeners start planning their responses to questions as soon as they can (Bögels, S., Magyari, L., & Levinson, S. C. (2015). Neural signatures of response planning occur midway through an incoming question in conversation. Scientific Reports, 5, 12881). The present study aimed to (1) replicate this early planning effect and (2) investigate whether such early response planning incurs a cost on participants’ concurrent comprehension of the ongoing turn. During the experiment participants answered questions from a confederate partner. To address aim (1), the questions were designed such that response planning could start either early or late in the turn. Our results largely replicate Bögels et al. (2015) showing a large positive ERP effect and an oscillatory alpha/beta reduction right after participants could have first started planning their verbal response, again suggesting an early start of response planning. To address aim (2), the confederate's questions also contained either an expected word or an unexpected one to elicit a differential N400 effect, either before or after the start of response planning. We hypothesized an attenuated N400 effect after response planning had started. In contrast, the N400 effects before and after planning did not differ. There was, however, a positive correlation between participants' response time and their N400 effect size after planning had started; quick responders showed a smaller N400 effect, suggesting reduced attention to comprehension and possibly reduced anticipatory processing. We conclude that early response planning can indeed impact comprehension processing.

Everyday conversation requires listeners to quickly recognize verbal actions, so-called speech acts, from the underspecified linguistic code and prepare a relevant response within the tight time constraints of turn-taking. The goal of this study was to determine the time-course of speech act recognition by investigating oscillatory EEG activity during comprehension of spoken dialogue. Participants listened to short, spoken dialogues with target utterances that delivered three distinct speech acts (Answers, Declinations, Pre-offers). The targets were identical across conditions at lexico-syntactic and phonetic/prosodic levels but differed in the pragmatic interpretation of the speech act performed. Speech act comprehension was associated with reduced power in the alpha/beta bands just prior to Declination speech acts, relative to Answers and Pre-offers. In addition, we observed reduced power in the theta band during the beginning of Declinations, relative to Answers. Based on the role of alpha and beta desynchronization in anticipatory processes, the results are taken to indicate that anticipation plays a role in speech act recognition. Anticipation of speech acts could be critical for efficient turn-taking, allowing interactants to quickly recognize speech acts and respond within the tight time frame characteristic of conversation. The results show that anticipatory processes can be triggered by the characteristics of the interaction, including the speech act type.

Item does not contain fulltext In contrast to the large amount of dual-task research investigating the coordination of a linguistic and a non-linguistic task, little research has investigated how two linguistic tasks are coordinated. However, such research would greatly contribute to our understanding of how interlocutors combine speech planning and listening in conversation. In three dual-task experiments we studied how participants coordinated the processing of an auditory stimulus (S1), which was either a syllable or a tone, with selecting a name for a picture (S2). Two SOAs, of 0 ms and 1000 ms, were used. To vary the time required for lexical selection and to determine when lexical selection took place, the pictures were presented with categorically related or unrelated distractor words. In Experiment 1 participants responded overtly to both stimuli. In Experiments 2 and 3, S1 was not responded to overtly, but determined how to respond to S2, by naming the picture or reading the distractor aloud. Experiment 1 yielded additive effects of SOA and distractor type on the picture naming latencies. The presence of semantic interference at both SOAs indicated that lexical selection occurred after response selection for S1. With respect to the coordination of S1 and S2 processing, Experiments 2 and 3 yielded inconclusive results. In all experiments, syllables interfered more with picture naming than tones. This is likely because the syllables activated phonological representations also implicated in picture naming. The theoretical and methodological implications of the findings are discussed. 18 p.

This paper reviews the prospects for the cross-fertilization of conversation-analytic (CA) and neurocognitive studies of conversation, focusing on turn-taking. Although conversation is the primary ecological niche for language use, relatively little brain research has focused on interactive language use, partly due to the challenges of using brain-imaging methods that are controlled enough to perform sound experiments, but still reflect the rich and spontaneous nature of conversation. Recently, though, brain researchers have started to investigate conversational phenomena, for example by using 'overhearer' or controlled interaction paradigms. We review neuroimaging studies related to turn-taking and sequence organization, phenomena historically described by CA. These studies for example show early action recognition and immediate planning of responses midway during an incoming turn. The review discusses studies with an eye to a fruitful interchange between CA and neuroimaging research on conversation and an indication of how these disciplines can benefit from each other.

This study addresses the question whether prosodic information can affect the choice for a syntactic analysis in auditory sentence processing. We manipulated the prosody (in the form of a prosodic break; PB) of locally ambiguous Dutch sentences to favor one of two interpretations. The experimental items contained two different types of so-called control verbs (subject and object control) in the matrix clause and were syntactically disambiguated by a transitive or by an intransitive verb. In Experiment 1, we established the default off-line preference of the items for a transitive or an intransitive disambiguating verb with a visual and an auditory fragment completion test. The results suggested that subject- and object-control verbs differently affect the syntactic structure that listeners expect. In Experiment 2, we investigated these two types of verbs separately in an on-line ERP study. Consistent with the literature, the PB elicited a closure positive shift. Furthermore, in subject-control items, an N400 effect for intransitive relative to transitive disambiguating verbs was found, both for sentences with and for sentences without a PB. This result suggests that the default preference for subject-control verbs goes in the same direction as the effect of the PB. In object-control items, an N400 effect for intransitive relative to transitive disambiguating verbs was found for sentences with a PB but no effect in the absence of a PB. This indicates that a PB can affect the syntactic analysis that listeners pursue.

We investigate the timing of pre-answer inbreaths in order to shed light on the time course of response planning and execution in conversational turn-taking. Using acoustic and inductive plethysmography recordings of seven dyadic conversations in Dutch, we show that pre-answer inbreaths in conversation typically begin briefly after the end of questions. We also show that the presence of a pre-answer inbreath usually co-occurs with substantially delayed answers, with a modal latency of 576 vs. 100 ms for answers not preceded by an inbreath. Based on previously reported minimal latencies for internal intercostal activation and the production of speech sounds, we propose that vocal responses, either in the form of a pre-utterance inbreath or of speech proper when an inbreath is not produced, are typically launched in reaction to information present in the last portion of the interlocutor's turn. We also show that short responses are usually made on residual breath, while longer responses are more often preceded by an inbreath. This relation of inbreaths to answer length suggests that by the time an inbreath is launched, typically during the last few hundred milliseconds of the question, the length of the answer is often prepared to some extent. Together, our findings are consistent with a two-stage model of response planning in conversational turn-taking: early planning of content often carried out in overlap with the incoming turn, and late launching of articulation based on the identification of turn-final cues.

Item does not contain fulltext This ERP study investigates whether a superfluous prosodic break (i.e., a prosodic break that does not coincide with a syntactic break) has more severe processing consequences during auditory sentence comprehension than a missing prosodic break (i.e., the absence of a prosodic break at the position of a syntactic break). Participants listened to temporarily ambiguous sentences involving a prosody-syntax match or mismatch. The disambiguation of these sentences was always lexical in nature in the present experiment. This contrasts with a related study by Pauker, Itzhak, Baum, and Steinhauer (2011), where the disambiguation was of a lexical type for missing PBs and of a prosodic type for superfluous PBs. Our results converge with those of Pauker et al. (2011): superfluous prosodic breaks lead to more severe processing problems than missing prosodic breaks. Importantly, the present results extend those of Pauker et al. (2011) showing that this holds when the disambiguation is always lexical in nature. Furthermore, our results show that the way listeners use prosody can change over the course of the experiment which bears consequences for future studies. 14 p.

Item does not contain fulltext We investigated whether listeners are sensitive to (mis)matching accentuation patterns with respect to contrasts in the linguistic and visual context, using Event-Related Potentials. We presented participants with displays of two pictures followed by a spoken reference to one of these pictures (e.g., "the red ball"). The referent was contrastive with respect to the linguistic context (utterance in the previous trial: e.g., "the blue ball") or with respect to the visual context (other picture in the display; e.g., a display with a red ball and a blue ball). The spoken reference carried a pitch accent on the noun ("the red BALL") or on the adjective ("the RED ball"), or an intermediate ('neutral') accentuation. For the linguistic context, we found evidence for the Missing Accent Hypothesis: Listeners showed processing difficulties, in the form of increased negativities in the ERPs, for missing accents, but not for superfluous accents. 'Neutral' or intermediate accents were interpreted as 'missing' accents when they occurred late in the referential utterance, but not when they occurred early. For the visual context, we found evidence for the Missing Accent Hypothesis for a missing accent on the adjective (an increase in negativity in the ERPs) and a superfluous accent on the noun (no effect). However, a redundant color adjective (e.g., in the case of a display with a red ball and a red hat) led to less processing problems when the adjective carried a pitch accent.

independent component analysis and current-source density. Behaviorally, the depressed sample showed less accurate heartbeat perception in comparison to the control group (p=.011). The two groups alsodemonstrated psychophysiological differences, showing that heartbeat-evoked potentials were significantly reduced in depressed patients. Our results suggest that heartbeat evoked potentials are objective markers of altered bodily awareness. Reduced interoception during depression may be linked to alexithymia, as well as to both decreased capacity for decision-making and for cognitive processing. It may be helpful to practice interoceptive awareness to improve depressive symptoms, for example by practicing meditation.