"If you catch my drift...": ability to infer implied meaning is distinct from vocabulary and grammar skills

Individual Differences in Indirect Speech Act Processing Found Outside the Language Network

Face-to-face communication requires skills that go beyond core language abilities. In dialogue, we routinely make inferences beyond the literal meaning of utterances and distinguish between different speech acts based on, e.g., contextual cues. It is, however, not known whether such communicative skills potentially overlap with core language skills or other capacities, such as theory of mind (ToM). In this functional magnetic resonance imaging (fMRI) study we investigate these questions by capitalizing on individual variation in pragmatic skills in the general population. Based on behavioral data from 199 participants, we selected participants with higher vs. lower pragmatic skills for the fMRI study (N = 57). In the scanner, participants listened to dialogues including a direct or an indirect target utterance. The paradigm allowed participants at the whole group level to (passively) distinguish indirect from direct speech acts, as evidenced by a robust activity difference between these speech acts in an extended language network including ToM areas. Individual differences in pragmatic skills modulated activation in two additional regions outside the core language regions (one cluster in the left lateral parietal cortex and intraparietal sulcus and one in the precuneus). The behavioral results indicate segregation of pragmatic skill from core language and ToM. In conclusion, contextualized and multimodal communication requires a set of interrelated pragmatic processes that are neurocognitively segregated: (1) from core language and (2) partly from ToM.

Stage 2 registered report: investigating a preference for certainty in conversation among autistic adults

Social communication difficulties are a diagnostic feature in autism. These difficulties are sometimes attributed, at least in part, to impaired ability in making inferences about what other people mean. In this registered report, we tested a competing hypothesis that the communication profile of adults on the autism spectrum can be more strongly characterised by reduced confidence in making inferences in the face of uncertain information. We tested this hypothesis by comparing the performance of 102 autistic and 109 non-autistic adults on a test of implied meaning, using a test of grammaticality judgements as a control task. We hypothesised that autistic adults would report substantially lower confidence, allowing for differences in accuracy, than non-autistic adults on the test of implied meaning compared to the grammaticality test. However, our results did not suggest this. Instead, we found that accuracy and confidence were both reduced to a similar extent on the test of implied meaning in the autistic group compared to the control group, although these were only subtle differences. This pattern of results was specific to inference-making, as the autistic and non-autistic groups did not differ on the grammar test. This supports the idea that specific differences in pragmatic language processing can exist in autism in the absence of core language problems. Importantly, this pattern of results (differences on the test of implied meaning and no differences on the grammar test) was reversed in a group with self-reported reading difficulties, indicating that the differences in inference-making were specific to the autistic group. Lastly, we found relationships between Intolerance of Uncertainty, performance on the test of implied meaning, and self-reported social communication challenges. This supports the idea that discomfort with uncertainty plays a role in the pragmatic language and communication challenges in autism.

Development and validation of the conversation questionnaire: A psychometric measure of communication challenges generated from the self-reports of autistic people

Existing measures of communication challenges in autism are based on diagnostic criteria and research/clinical observations of autistic people, rather than what autistic people themselves identify as difficulties. In this study, the Conversation Questionnaire (CQ) was developed based on community engagement with autistic people to identify what they find challenging about conversation. This new tool was then administered online to autistic, dyslexic and neurotypical people (N = 312) in a validation phase of the study. Item-response theory modelling indicated that a two-dimensional structure accounted for response patterns. These dimensions reflected difficulties knowing what to say (15 items) and engaging in behaviours possibly disruptive to neurotypical conversation (21 items). The dimensions showed good internal consistency and convergent and discriminant validity, and could distinguish between autistic and neurotypical people (d = 1.59 and d = 2.07 respectively). The CQ might help contribute to diagnostic assessment for autism in adults as part of a holistic assessment. The questionnaire might also be useful with other neurodiverse groups, and provide a tool for clinicians and researchers to identify individuals' strengths and difficulties in conversation (e.g., as part of interventions in speech and language therapy).

Registered report: investigating a preference for certainty in conversation among autistic adults compared to dyslexic adults and the general population

Social communication difficulties are a diagnostic feature in autism. These difficulties are sometimes attributed, at least in part, to impaired ability in making inferences about what other people mean. In this registered report, we test a competing hypothesis that the communication profile of adults on the autism spectrum can be more strongly characterised by reduced confidence in making inferences in the face of uncertain information. We will test this hypothesis by comparing the performance of 100 autistic and 100 non-autistic adults on a test of implied meaning, using a test of grammaticality judgements as a control task. We hypothesise that autistic adults will report substantially lower confidence, allowing for differences in accuracy, than non-autistic adults on the test of implied meaning compared to the grammaticality test. In addition, we hypothesise that reduced confidence in drawing inferences will relate to the cognitive trait Intolerance of Uncertainty and self-reported social communication challenges. Finally, we will conduct exploratory analysis to assess the specificity of the communication profile of the autistic adults by comparing their performance to that of dyslexic adults, who might also be expected to experience challenges with language and communication.