Are foreign-accented speakers that 'incredible'? The impact of the speaker's indexical properties on sentence processing

Speaker Demographics Modulate Listeners' Neural Correlates of Spoken Word Processing

In language comprehension, listeners expect a speaker to be consistent in their word choice for labeling the same object. For instance, if a speaker previously refers to a piece of furniture as a "couch," in subsequent references, listeners would expect the speaker to repeat this label instead of switching to an alternative label such as "sofa." Moreover, it has been found that speakers' demographic backgrounds, often inferred from their voice, influence how listeners process their language. The question in focus, therefore, is whether speaker demographics influence how listeners expect the speaker to repeat or switch labels. In this study, we used ERPs to investigate whether listeners expect a child speaker to be less likely to switch labels compared to an adult speaker, given the common belief that children are less flexible in language use. In the experiment, we used 80 pictures with alternative labels in Mandarin Chinese (e.g., yi1sheng1 vs. dai4fu, "doctor"). Each picture was presented twice over two experimental phases: In the establishment phase, participants listened to an adult or a child naming a picture with one of the labels and decided whether the label matched the picture they saw; in the test phase, participants listened to the same speaker naming the same picture by either repeating the original label or switching to an alternative label and, again, decided whether the label matched the picture they saw. ERP results in the test phase revealed that, compared to repeated labels, switched labels elicited an N400 effect (300-600 msec after label onset) and a P600 effect (600-1000 msec after label onset). Critically, the N400 effect was larger when listeners were exposed to the child speaker than to the adult speaker, suggesting that listeners found a switched label harder to comprehend when it was produced by a child speaker than an adult speaker. Our study shows that the perceived speaker demographic backgrounds influence listeners' neural responses to spoken words, particularly in relation to their expectations regarding the speaker's label switching behavior. This finding contributes to a broader understanding of the relationship between social cognition and language processing.

Does Foreign-Accented Speech Affect Credibility? Evidence from the Illusory-Truth Paradigm

In a pioneering study, Lev-Ari and Keysar (2010) observed that unknown statements are judged less credible when uttered with foreign accent compared to native accent. This finding was interpreted in terms of processing fluency; when intelligibility is reduced, the credibility of the message decreases. Here, we use the illusory truth paradigm to explore how accent affects credibility. In a between-participant design, participants were exposed to unknown statements uttered by native-accented or foreign-accented speakers. After a distractor task, the same statements were presented with new statements, and participants assessed their truthfulness. Truthfulness ratings were higher for repeated statements than for new statements, replicating the illusory truth effect. Contrary to the processing fluency hypothesis, the effect was similar in both the foreign-accented and native-accented speech groups. A new group of participants rated the speakers' voices on various social traits. A negative bias against foreign speakers was observed. However, this negative-bias did not affect truth ratings.The impact of foreign-accented speech on message credibility is discussed in the context of two factors, processing fluency and out-group stereotype activation.

Complain like you mean it! How prosody conveys suffering even about innocuous events

When complaining, speakers can use their voice to convey a feeling of pain, even when describing innocuous events. Rapid detection of emotive and identity features of the voice may constrain how the semantic content of complaints is processed, as indexed by N400 and P600 effects evoked by the final, pain-related word. Twenty-six participants listened to statements describing painful and innocuous events expressed in a neutral or complaining voice, produced by ingroup and outgroup accented speakers. Participants evaluated how hurt the speaker felt under EEG monitoring. Principal Component Analysis of Event-Related Potentials from the final word onset demonstrated N400 and P600 increases when complainers described innocuous vs. painful events in a neutral voice, but these effects were altered when utterances were expressed in a complaining voice. Independent of prosody, N400 amplitudes increased for complaints spoken in outgroup vs. ingroup accents. Results demonstrate that prosody and accent constrain the processing of spoken complaints as proposed in a parallel-constraint-satisfaction model.

Would you respect a norm if it sounds foreign? Foreign-accented speech affects decision-making processes

Does listening to a foreign-accented speaker bias native speakers' behavior? We investigated whether the accent, i.e., a foreign accent versus a native accent, in which a social norm is presented affects native speakers' decision to respect the norm (Experiments 1 and 2) and the judgement for not respecting it (Experiment 2). In Experiment 1, we presented 128 native Spanish speakers with new social norms, adapted from the measures imposed by the Spanish Government to fight the Covid-19 pandemic (e.g., 'To avoid the spread of the Covid-19 virus, keep your distance'), whereas in Experiment 2, we presented 240 native Spanish speakers with everyday social norms learned from childhood (e.g., 'Not littering on the street or in public places'), that have an intrinsic cultural and linguistic link. In Experiment 1, the norms were uttered either in a native accent, or in a foreign accent unfamiliar to our participants to avoid stereotypes. In Experiment 2, we added an accent negatively perceived in Spain to assess the role of language attitudes on decision making. Overall, accent did not directly impact participants' final decisions, but it influenced the decision-making process. The factors that seem to underlie this effect are emotionality and language attitudes. These findings add up to the recent Foreign Accent effect observed on moral judgements and further highlight the role of the speaker's identity in decision making.

Listen to my feelings! How prosody and accent drive the empathic relevance of complaining speech

Interpersonal communication often involves sharing our feelings with others; complaining, for example, aims to elicit empathy in listeners by vocally expressing a speaker's suffering. Despite the growing neuroscientific interest in the phenomenon of empathy, few have investigated how it is elicited in real time by vocal signals (prosody), and how this might be affected by interpersonal factors, such as a speaker's cultural background (based on their accent). To investigate the neural processes at play when hearing spoken complaints, twenty-six French participants listened to complaining and neutral utterances produced by in-group French and out-group Québécois (i.e., French-Canadian) speakers. Participants rated how hurt the speaker felt while their cerebral activity was monitored with electroencephalography (EEG). Principal Component Analysis of Event-Related Potentials (ERPs) taken at utterance onset showed culture-dependent time courses of emotive prosody processing. The high motivational relevance of ingroup complaints increased the P200 response compared to all other utterance types; in contrast, outgroup complaints selectively elicited an early posterior negativity in the same time window, followed by an increased N400 (due to ongoing effort to derive affective meaning from outgroup voices). Ingroup neutral utterances evoked a late negativity which may reflect re-analysis of emotively less salient, but culturally relevant ingroup speech. Results highlight the time-course of neurocognitive responses that contribute to emotive speech processing for complaints, establishing the critical role of prosody as well as social-relational factors (i.e., cultural identity) on how listeners are likely to "empathize" with a speaker.

When A Nonnative Accent Lets You Spot All the Errors: Examining the Syntactic Interlanguage Benefit

In our continuously globalizing world, cross-cultural and cross-linguistic communications are far from exceptional. A wealth of research has indicated that the processing of nonnative-accented speech can be challenging for native listeners, both at the level of phonology (e.g., Munro & Derwing, 1995) and syntax (Caffarra & Martin, 2019). However, few online studies have examined the underpinnings of accented speech recognition from the perspective of the "nonnative listener," even though behavioral studies indicate that accented input may be easier to process for such individuals (i.e., the interlanguage speech intelligibility benefit; Bent & Bradlow, 2003). The current EEG study first examined the phonological and syntactic analysis of nonnative-accented speech among nonnative listeners. As such, 30 English learners of Spanish listened to syntactically correct and incorrect Spanish sentences produced in native and nonnative-accented Spanish. The violation in the incorrect sentences was caused by errors that are typical (i.e., gender errors; *la color) or atypical for English learners of Spanish (i.e., number errors; *los color). Results indicated that nonnative listeners elicit a phonological mismatch negativity (PMN) when attending to speech produced by a native Spanish speaker. Furthermore, the nonnative listeners showed a P600 for all grammatical violations, indicating that they repair all errors regardless of their typicality or the accent in which they are produced. Follow-up analyses compared our novel data to the data of native listeners from the methodologically identical precursor study (Caffarra & Martin, 2019). These analyses showed that native and nonnative listeners exhibit directionally opposite PMN effects; whereas natives exhibited a larger PMN for English-accented Spanish, nonnatives displayed a larger PMN in response to native Spanish utterances (a classic interlanguage speech intelligibility benefit). An additional difference was observed at the syntactic level: Whereas natives repaired only atypical number errors when they were English-accented, nonnative participants exhibited a P600 in response to all English-accented syntactic errors, regardless of their typicality (a syntactic interlanguage speech intelligibility benefit). Altogether, these results suggest that accented speech is not inherently difficult to process; in fact, nonnatives may benefit from the presence of a nonnative accent. Thus, our data provide some of the first electrophysiological evidence supporting the existence of the classic interlanguage speech intelligibility benefit and its novel syntactic counterpart.

Is There a Foreign Accent Effect on Moral Judgment?

Recent studies have shown that people make more utilitarian decisions when dealing with a moral dilemma in a foreign language than in their native language. Emotion, cognitive load, and psychological distance have been put forward as explanations for this foreign language effect. The question that arises is whether a similar effect would be observed when processing a dilemma in one’s own language but spoken by a foreign-accented speaker. Indeed, foreign-accented speech has been shown to modulate emotion processing, to disrupt processing fluency and to increase psychological distance due to social categorisation. We tested this hypothesis by presenting 435 participants with two moral dilemmas, the trolley dilemma and the footbridge dilemma online, either in a native accent or a foreign accent. In Experiment 1, 184 native Spanish speakers listened to the dilemmas in Spanish recorded by a native speaker, a British English or a Cameroonian native speaker. In Experiment 2, 251 Dutch native speakers listened to the dilemmas in Dutch in their native accent, in a British English, a Turkish, or in a French accent. Results showed an increase in utilitarian decisions for the Cameroonian- and French-accented speech compared to the Spanish or Dutch native accent, respectively. When collapsing all the speakers from the two experiments, a similar increase in the foreign accent condition compared with the native accent condition was observed. This study is the first demonstration of a foreign accent effect on moral judgements, and despite the variability in the effect across accents, the findings suggest that a foreign accent, like a foreign language, is a linguistic context that modulates (neuro)cognitive mechanisms, and consequently, impacts our behaviour. More research is needed to follow up on this exploratory study and to understand the influence of factors such as emotion reduction, cognitive load, psychological distance, and speaker’s idiosyncratic features on moral judgments.