Anna K. Kuhlen

Language control in bilinguals: Intention to speak vs. execution of speech

Bilinguals require a high degree of cognitive control to select the language intended for speaking and inhibit the unintended. Previous neuroimaging studies have not teased apart brain regions for generating the intention to use a given language, and those for speaking in that language. Separating these two phases can clarify at what stage competition between languages occurs. In this fMRI study German-English bilinguals were first cued to use German or English. After a delay, they named a picture in the cued language. During the intention phase, the precuneus, right superior lateral parietal lobule, and middle temporal gyrus were more activated when participants had to update the currently active language. During language execution activation was higher for English compared to German in brain areas associated with cognitive control, most notably the anterior cingulate and the caudate. Our results suggest two different systems enabling cognitive control during bilingual language production.

Neural coding of assessing another person’s knowledge based on nonverbal cues

For successful communication, conversational partners need to estimate each others current knowledge state. Nonverbal facial and bodily cues can reveal relevant information about how confident a speaker is about what they are saying. Using functional magnetic resonance imaging, we aimed to identify brain regions that encode how confident a speaker is perceived to be. Participants viewed videos of people answering general knowledge questions and judged each respondents confidence in their answer. Our results suggest a distinct role of two neural networks known to support social inferences, the so-called mentalizing and the mirroring network. While activation in both networks underlies the processing of nonverbal cues, only activity in the mentalizing network, most notably the medial prefrontal cortex and the bilateral temporoparietal junction, is modulated by how confident the respondent is judged to be. Our results support an integrative account of the mirroring and mentalizing network, in which the two systems support each other in aiding pragmatic processing.

Gesturing integrates top-down and bottom-up information: Joint effects of speakers' expectations and addressees' feedback

Abstract Speakers adapt their speech based on both prior expectations and incoming cues about their addressees’ informational needs (Kuhlen and Brennan 2010). Here, we investigate whether top-down information, such as speakers’ expectations about addressees’ attentiveness, and bottom-up cues, such as addressees’ feedback during conversation, also influence speakers’ gestures. In 39 dyads, addressees were either attentive when speakers told a joke or else distracted by a second task, while speakers expected addressees to be either attentive or distracted. Independently of adjustments in speech, both speakers’ expectations and addressees’ feedback shaped quantitative and qualitative aspects of gesturing. Speakers gestured more frequently when their prior expectations matched addressees’ actual behavior. Moreover, speakers with attentive addressees gestured more in the periphery of gesture space when they expected addressees to be attentive. These systematic adjustments in gesturing suggest that speakers flexibly adapt to their addressees by integrating bottom-up cues available during the interaction in light of attributions made from top-down expectations. That these sources of information lead to adjustments patterning similarly in speech and gesture informs theoretical frameworks of how different modalities are deployed and coordinated in dialogue.

Brains in dialogue: decoding neural preparation of speaking to a conversational partner

Abstract In dialogue, language processing is adapted to the conversational partner. We hypothesize that the brain facilitates partner-adapted language processing through preparatory neural configurations (task sets) that are tailored to the conversational partner. In this experiment, we measured neural activity with functional magnetic resonance imaging (fMRI) while healthy participants in the scanner (a) engaged in a verbal communication task with a conversational partner outside of the scanner, or (b) spoke outside of a conversational context (to test the microphone). Using multivariate searchlight analysis, we identify cortical regions that represent information on whether speakers plan to speak to a conversational partner or without having a partner. Most notably a region that has been associated with processing social-affective information and perspective taking, the ventromedial prefrontal cortex, as well as regions that have been associated with prospective task representation, the bilateral ventral prefrontal cortex, are involved in encoding the speaking condition. Our results suggest that speakers prepare, in advance of speaking, for the social context in which they will speak.