Predictions allow for efficient human communication. To be efficient, listeners’ predictions need to be adapted to the communicative context. Here we show that during speech processing this adaptation is a highly flexible and selective process that is able to fine-tune itself to individual language styles of specific interlocutors. In a newly developed paradigm, speakers differed in the probabilities by which they used particular sentence structures. Probe trials were applied to infer participants’ syntactic expectations for a given speaker and to track changes of these expectations over time. The results show that listeners fine-tune their linguistic expectations according to the individual language style of a speaker. Strikingly, nine months after the initial experiment these highly specific expectations could be rapidly reactivated when confronted with the particular language style of a speaker but not merely on the basis of an association with speaker identity per se. These findings highlight that communicative interaction fine-tunes and consolidates interlocutor specific communicative predictions which can overrule strong linguistic priors.

Physical distance is a prominent feature in face-to-face social interactions and allows regulating social encounters. Close interpersonal distance (IPD) increases emotional responses during interaction and has been related to avoidance behavior in social anxiety. However, a systematic investigation of the effects of IPD on subjective experience combined with measures of physiological arousal and behavioral responses during real-time social interaction has been missing. Virtual Reality allows for a controlled manipulation of IPD while maintaining naturalistic social encounters. The present study investigates IPD in social interaction using a novel paradigm in Virtual Reality. Thirty-six participants approached virtual agents and engaged in short interactions. IPD was varied between 3.5 and 1 m by manipulating the distance at which agents reacted to the participant's approach. Closer distances were rated as more arousing, less pleasant, and less natural than longer distances and this effect was significantly modulated by social anxiety scores. Skin conductance responses were also increased at short distances compared to longer distances. Finally, an interaction of IPD and social anxiety was observed for avoidance behavior, measured as participants' backward motion during interaction, with stronger avoidance related to close distances and high values of social anxiety. These results highlight the influence of IPD on experience, physiological response, and behavior during social interaction. The interaction of social anxiety and IPD suggests including the manipulation of IPD in behavioral tests in Virtual Reality as a promising tool for the treatment of social anxiety disorder.

46Sentence comprehension requires the rapid analysis of semantic and syntactic 47 information. These processes are supported by a left hemispheric dominant fronto-48 temporal network, including left posterior inferior frontal gyrus (pIFG) and posterior 49 superior temporal gyrus/sulcus (pSTG/STS). Previous electroencephalography 50 (EEG) studies have associated semantic expectancy within a sentence with a 51 modulation of the N400 and syntactic gender violations with increases in the LAN 52 and P600. Here, we combined focal perturbations of neural activity by means of short 53 bursts of transcranial magnetic stimulation (TMS) with simultaneous EEG recordings 54 to probe the functional relevance of pIFG and pSTG/STS for sentence 55 comprehension. We applied 10 Hz TMS bursts of three pulses at verb onset during 56 auditory presentation of short sentences. Verb-based semantic expectancy and 57 article-based syntactic gender requirement were manipulated for the sentence final 58 noun. We did not find any TMS effect at the noun. However, TMS had a short-lasting 59 impact at the mid-sentence verb that differed for the two stimulation sites. 60Specifically, TMS over pIFG elicited a frontal positivity in the first 200 ms post verb 61 onset whereas TMS over pSTG/STS was limited to a parietal negativity at 200-400 62 ms post verb onset. This indicates that during verb processing in sentential context, 63 frontal brain areas play an earlier role than temporal areas in predicting the upcoming 64 noun. The short-living perturbation effects at the mid-sentence verb suggest a high 65 degree of online compensation within the language system since the sentence final 66 noun processing was unaffected. 67 68 69 70

During the COVID-19 pandemic several behavioral measures have been implemented to reduce viral transmission. While these measures reduce the risk of infections, they may also increase risk behavior. Here, we experimentally investigate the influence of face masks on physical distancing. Eighty-four participants with or without face masks passed virtual agents in a supermarket environment to reach a target while interpersonal distance was recorded. Agents differed in wearing face masks and age (young, elderly). In addition, situational constraints varied in whether keeping a distance of 1.5 m required an effortful detour or not. Wearing face masks (both self and other) reduced physical distancing. This reduction was most prominent when keeping the recommended distance was effortful, suggesting an influence of situational constraints. Similarly, increased distances to elderly were only observed when keeping a recommended distance was effortless. These findings highlight contextual constraints in compensation behavior and have important implications for safety policies.

Background Habits and behaviors in everyday life currently need to be modified as quickly as possible due to the COVID-19 pandemic. Two of the most effective tools to prevent infection seem to be regular and thorough hand-washing and physical distancing during interpersonal interactions. Method Two hundred and eighty-four participants completed a short survey to investigate how previous habits regarding hand-washing and physical distancing have changed in the general population as a function of the current pandemic and the thereby increased information and constant recommendations regarding these behaviors. Results Participants aged 51 and older reported a greater change in everyday hand-washing behavior than younger participants. In addition, participants aged 31 and older selected significantly greater distances to have a conversation than younger participants. However, that was not the case if participants had to actively stop their conversational partner from approaching. Conclusion Participants aged 51 years and older seem to be well aware of their at-risk status during the current pandemic and might therefore be willing to change their behavior more strongly than younger survey participants. Nevertheless, they seem to struggle with enforcing the current rules towards others. The group aged between 31 and 50 years, however, reports a comparable level of fear, but no corresponding change in hand-washing behavior. Future surveys should try to provide more insight into why this might be the case.

Effective natural communication requires listeners not only to incorporate very general linguistic principles which evolved during a life time, but also other information like the specific individual language use of a particular interlocutor. Traditionally, research has focused on the general linguistic rules and brain-science has shown a left hemispheric fronto-temporal brain network related to this processing. The present fMRI-research explores speaker-specific individual language use because it is unknown whether this processing is supported by similar or distinct neural structures. Twenty-eight participants listened to sentences of persons who spoke easy or more difficult. This was done by manipulating the proportion of easy SOV vs. complex OSV sentences for each speaker. Furthermore, ambiguous probe sentences were included to test top-down influences of speaker information in the absence of syntactic structure information. We observed distinct neural processing for syntactic complexity and speaker-specific language use. Syntactic complexity correlated with left frontal and posterior temporal regions. Speaker-specific processing correlated with bilateral (right-dominant) fronto-parietal brain regions. Finally, the top-down influence of speaker information was found in frontal and striatal brain regions, suggesting a mechanism for controlled syntactic processing. These findings show distinct neural networks related to general language principles as well as speaker-specific individual language use.

Social interaction requires fast and efficient processing of another person’s intentions. In face-to-face interactions, aversive or appetitive actions typically co-occur with emotional expressions, allowing an observer to anticipate action intentions. In the present study, we investigated the influence of facial emotions on the processing of action intentions. Thirty-two participants were presented with video clips showing virtual agents displaying a facial emotion (angry vs. happy) while performing an action (punch vs. fist-bump) directed towards the observer. During each trial, video clips stopped at varying durations of the unfolding action, and participants had to recognize the presented action. Naturally, participants’ recognition accuracy improved with increasing duration of the unfolding actions. Interestingly, while facial emotions did not influence accuracy, there was a significant influence on participants’ action judgements. Participants were more likely to judge a presented action as a punch when agents showed an angry compared to a happy facial emotion. This effect was more pronounced in short video clips, showing only the beginning of an unfolding action, than in long video clips, showing near-complete actions. These results suggest that facial emotions influence anticipatory processing of action intentions allowing for fast and adaptive responses in social interactions.

During the Covid-19 pandemic several behavioral measures have been implemented to reduce viral transmission. While these measures reduce the risk of infections, they may also increase risk behavior. Here, we experimentally investigate the influence of face masks on physical distancing. Eighty-four participants with or without face masks passed virtual agents in a supermarket environment to reach a target while interpersonal distance was recorded. Agents differed in wearing face masks and age (young, elderly). In addition, situational constraints varied in whether keeping a distance of 1.5 m required an effortful detour or not. Wearing face masks (both self and other) reduced physical distancing. This reduction was most prominent when keeping the recommended distance was effortful, suggesting an influence of situational constraints. Similarly, increased distances to elderly were only observed when keeping a recommended distance was effortless. These findings highlight contextual constraints in compensation behavior and have important implications for safety policies.