Presentations

Abstract

When talking, speakers continuously monitor the auditory feedback of their own voice to control and inform speech production processes. When speakers are provided with auditory feedback that is perturbed in real time, most of them compensate for this by opposing the feedback perturbation. For example, when speakers hear themselves at a higher pitch than intended, they would compensate by lowering their pitch. However, sometimes speakers follow the perturbation instead (i.e., raising their pitch in response to higher-than-expected pitch). Current theoretical frameworks cannot account for following responses. In the current study, we performed two experiments to investigate whether the state of the speech production system at perturbation onset may determine what type of response (opposing or following) is given. Participants vocalized while the pitch in their auditory feedback was briefly (500 ms) perturbed in half of the vocalizations. None of the participants were aware of these manipulations. Subsequently, we analyzed the pitch contour of the participants’ vocalizations. The results suggest that whether a perturbation-related response is opposing or following unexpected feedback depends on ongoing fluctuations of the production system: It initially responds by doing the opposite of what it was doing. In addition, the results show that all speakers show both following and opposing responses, although the distribution of response types varies across individuals. Both the interaction with ongoing fluctuations and the non-trivial number of following responses suggest that current speech production models are inadequate. More generally, the current study indicates that looking beyond the average response can lead to a more complete view on the nature of feedback processing in motor control. Future work should explore whether the direction of feedback-based control in domains outside of speech production will also be conditional on the state of the motor system at the time of the perturbation.

Abstract

When talking, speakers continuously monitor and use the auditory feedback of their own voice to control and inform speech production processes. Auditory feedback processing has been studied using perturbed auditory feedback. When speakers are provided with auditory feedback that is perturbed in real time, most of them compensate for this by opposing the feedback perturbation. For example, when speakers hear themselves at a higher pitch than intended, they would compensate by lowering their pitch. However, sometimes speakers follow the perturbation instead (i.e., raising their pitch in response to higher-than-expected pitch). Although most past studies observe some following responses, current theoretical frameworks cannot account for following responses. In addition, recent experimental work has suggested that following responses may be more common than has been assumed to date.
In the current study, we performed two experiments (N = 39 and N = 24) to investigate whether the state of the speech production system at perturbation onset may determine what type of response (opposing or following) is given. Participants vocalized while they tried to match a target pitch level. Meanwhile, the pitch in their auditory feedback was briefly (500 ms) perturbed in half of the vocalizations, increasing or decreasing pitch by 25 cents. None of the participants were aware of these manipulations. Subsequently, we analyzed the pitch contour of the participants’ vocalizations.
The results suggest that whether a perturbation-related response is opposing or following unexpected feedback depends on ongoing fluctuations of the production system: It initially responds by doing the opposite of what it was doing. In addition, the results show that all speakers show both following and opposing responses, although the distribution of response types varies across individuals.
Both the interaction with ongoing fluctuations of the speech system and the non-trivial proportion of following responses suggest that current production models are inadequate: They need to account for why responses to unexpected sensory feedback depend on the production-system’s state at the time of perturbation. More generally, the current study indicates that looking beyond the average response can lead to a more complete view on the nature of feedback processing in motor control. Future work should explore whether the direction of feedback-based control in domains outside of speech production will also be conditional on the state of the motor system at the time of the perturbation.

Abstract

A series of results from event-related brain potential recordings and fMRI research will be presented, suggesting that language processing does not obey strict compositionality, and, moreover immediately recruits extralinguistic information. It will also be shown that pragmatic inferences require contributions from TOM networks. This implies that an embodied account of semantics fails (under the somewhat strange assumption that the brain is not part of the body). I will put forward an embrained perspective on language processing.

Abstract

In my presentation I will summarize the results of a number of ERP and fMRI studies on the processing and integration of co-occurring speech and gestures/pantomimes. The ERP results indicate that the time course of integrating language and action (i.e., gesture) is very similar to that of integrating linguistic meaning into a sentence or discourse representation. Moreover, in both cases the Left Inferior Frontal cortex plays a central role in orchestrating the multimodal unification of language and action. This orchestration is partly done by modulating temporal areas that store representations activated by the input. I will discuss the parameters of this modulation.

Abstract

For over 20 years, researchers have investigated syntactic priming of transitives by measuring the frequency of sentence choice. These studies have shown syntactic priming for passives but weaker or absent syntactic priming for actives (e.g. [1],[2]). Until recently very few studies have reported syntactic priming by measuring reaction times of language production and none of these studies included transitive sentences. We previously found syntactic priming of both active and passive Dutch transitives in speech onsets, and interestingly the effect appeared to be stronger for actives than passives [3][4]. In order to explain the discrepancy between our results and other results reported in the literature, we hypothesized that there is a ceiling effect in the frequency of using an active transitive (in general about 94% of produced transitives are actives) but not in the speed of producing one. To confirm this hypothesis we conducted a syntactic priming experiment with a picture description task measuring both reaction times and the frequency of occurrence on the same trials. This way we could exclude the alternative explanation that the discrepancy in results is caused by differences in design or stimuli. The results of this experiment show syntactic priming effects for passives and not for actives in the frequency of occurrence (in line with the literature). However, the reaction times of producing these sentences do show syntactic priming for actives and these effects appear to be even stronger than for passives (in line with our previous data). In conclusion, our results suggest that measuring the frequency of occurrence is not enough to get a complete picture of syntactic priming. Measuring reaction times in addition to the frequency of occurrence could provide us with a more complete picture. References [1] Bock, K., & Loebell, H. (1990). Framing sentences. Cognition, 35, 1-39. [2] Hartsuiker, R. J., & Kolk, H. H. J. (1998). Syntactic persistence in Dutch sentence production. Language and Speech, 41, 143-184. [3] Menenti, L., Segaert, K., & Hagoort, P. (2008). Repetition suppression for syntax and semantics: overt speech in fMRI. Society for Neuroscience, Washington DC. [4] Segaert, K., Menenti, L., & Hagoort, P. (2009) Scanning speech with fMRI: Short and long term priming of syntax and verbs, CUNY conference on human sentence processing, Davis, CA.

Abstract

Syntactic priming has been frequently used to study syntactic processes in language production in monolinguals [1][2] and bilinguals [3]. In a previous study in language comprehension [4] we showed that passive sentences in English (the participant’s L2) can be primed by passive sentences in German (L1) and English (L2). This was manifested in faster reading times for target sentences and repetition suppression effects in left inferior frontal, left precentral and left middle temporal regions of interest in an fMRI study. However, syntactic priming in comprehension is complicated by the influence of verb repetition between prime and target [5][6]. Therefore, we conducted a reading time and fMRI study looking at the influence of verb repetition on syntactic priming. In this study of monolingual comprehension in Dutch we primed passive sentences as well as sentences with crossed-dependency structures. The reading time results revealed a syntactic priming effect for passive sentences, while the effect for crossed-dependency structure sentences interacted with the factor verb repetition. The preliminary fMRI results suggest that the repetition of passive structures leads to reductions in neural activity. The repetition of crossed dependency structures causes repetition enhancement, an increase in the BOLD response, an effect that interacts with the factor verb repetition. In conclusion, the influence of verb repetition on syntactic priming in comprehension is complex and seems to depend on the type of syntactic structure investigated. References [1] Bock K. (1986). Syntactic persistence in language production. Cognitive Psychology, 18(3), 355-387. [2] Pickering M, & Branigan H. (1999). Syntactic priming in language production. Trends in Cognitive Sciences, 3(4), 136-141. [3] Schoonbaert S, Hartsuiker RJ, & Pickering MJ. (2007). The representation of lexical and syntactic information in bilinguals: Evidence from syntactic priming. Journal of Memory and Language, 56(2), 153-171. [4] Weber K, & Indefrey P. (in press). Syntactic priming in German-English bilinguals during sentence comprehension. NeuroImage. [5] Arai M, van Gompel R, & Scheepers C. (2007). Priming ditransitive structures in comprehension. Cognitive Psychology, 54, 218-250. [6] Thothathiri M, & Snedeker J. (2008). Give and take: Syntactic priming during spoken language comprehension. Cognition, 108(1), 51-68.