The Understanding of Scalar Implicatures in Children With Autism Spectrum Disorder: Dichotomized Responses to Violations of Informativeness

Variability of theory of mind versus pragmatic ability in typical and atypical development

INTRODUCTION

Numerous studies have linked deficits in Theory of Mind (ToM) with language problems. We aimed to explore the similarities and differences between children's patterns of performance on a ToM task that requires minimal linguistic skill and a pragmatic inference task that relies on both ToM and language. We assessed variability in pragmatic inference skills and ToM across populations of children (8-14 years) displaying varying cognitive profiles. We further compared the sensitivity of ToM versus pragmatic ability to core language skills, memory and executive functioning (EF).

METHOD

ToM was tested using the Social Attribution Task (SAT-MC-II). Pragmatic ability was assessed in an implicature comprehension task. Receptive vocabulary, grammar comprehension, short-term and working memory (STM and WM) capacity and EF were measured using Hungarian adaptations of standard tasks and tests developed by the authors' lab. In addition to typically developing (TD) children (n = 33), we included children with neurodevelopmental disorders where ToM and/or language abilities are vulnerable: autism spectrum disorder (ASD, n = 26), attention deficit hyperactivity disorder (ADHD, n = 25) and developmental language disorder (DLD, n = 18).

RESULTS

Results revealed a significant but only moderate positive correlation between pragmatic inference and ToM indicating that the two abilities are related but distinct. The ASD group showed impairments in both ToM and pragmatic inference ability but no significant deficit was observed in ADHD or DLD relative to TD children in either skill. However, while SAT-MC-II results were only affected by verbal WM and vocabulary measures, pragmatic performance was associated with STM, verbal WM, EF, grammatical skills and vocabulary.

CONCLUSION

Our findings indicate that disentangling the contributions of different cognitive skills to ToM tasks may help clarify the role of ToM in language skills and identify distinct patterns of ToM and pragmatic skills in developmental disorders.

Challenges with computing scalar and ad-hoc implicatures in Mandarin-speaking 4-8-year-old autistic children

INTRODUCTION

Mixed findings have been reported about the computation of scalar or/and ad-hoc implicatures in primarily school-age autistic verbal children and adolescents: while some studies reported their struggles with both implicatures, others observed their strengths in computing scalar implicatures. This study extends the previous investigation by testing the derivation of scalar (including both number and quantifier) and ad-hoc implicatures of a younger group of Mandarin-speaking autistic 4-8-year-olds; moreover, we assess the biological, linguistic, and cognitive factors affecting children's implicature acquisition.

METHODS

The participants included 22 4-8-year-old autistic verbal children (mean age = 67.64 months) and 19 typically developing (TD) children who did not significantly differ in age, receptive vocabulary, and non-verbal IQ. Both groups completed a computer-based Truth Value Judgment task, assessing their knowledge of scalar (involving the number 'three' and the quantifier 'some') and ad-hoc implicatures. We also examined whether their implicature computation was linked to age, receptive vocabulary, non-verbal IQ, and Theory of Mind (ToM).

RESULTS

Compared with the TD controls, autistic children derived significantly fewer scalar and ad-hoc implicatures. Specifically, TD children successfully computed number and ad-hoc implicatures, contrasting to the bimodal distribution of their pragmatic vs. logical responses to quantifier implicatures. Though autistic children performed better with number implicatures slightly above the chance level, they had difficulties in computing quantifier and ad-hoc implicatures. Further, autistic children's knowledge of the number and ad-hoc implicatures was linked to their ToM skills.

CONCLUSIONS

These findings underscore the overall delayed implicature knowledge of young autistic children, and their low sensitivity to the implicatures is related to the core ToM deficits. Furthermore, our data confirm the coherent pattern of the earlier acquisition of number over quantifier implicatures and illuminate the distinct mechanisms underlying the computation of scalar vs. ad-hoc implicatures.

Language in autism: domains, profiles and co-occurring conditions

This article reviews the current knowledge state on pragmatic and structural language abilities in autism and their potential relation to extralinguistic abilities and autistic traits. The focus is on questions regarding autism language profiles with varying degrees of (selective) impairment and with respect to potential comorbidity of autism and language impairment: Is language impairment in autism the co-occurrence of two distinct conditions (comorbidity), a consequence of autism itself (no comorbidity), or one possible combination from a series of neurodevelopmental properties (dimensional approach)? As for language profiles in autism, three main groups are identified, namely, (i) verbal autistic individuals without structural language impairment, (ii) verbal autistic individuals with structural language impairment, and (iii) minimally verbal autistic individuals. However, this tripartite distinction hides enormous linguistic heterogeneity. Regarding the nature of language impairment in autism, there is currently no model of how language difficulties may interact with autism characteristics and with various extralinguistic cognitive abilities. Building such a model requires carefully designed explorations that address specific aspects of language and extralinguistic cognition. This should lead to a fundamental increase in our understanding of language impairment in autism, thereby paving the way for a substantial contribution to the question of how to best characterize neurodevelopmental disorders.

Linking metaphor comprehension with analogical reasoning: Evidence from typical development and autism spectrum disorder

We examined the relationship between metaphor comprehension and verbal analogical reasoning in young adults who were either typically developing (TD) or diagnosed with Autism Spectrum Disorder (ASD). The ASD sample was highly educated and high in verbal ability, and closely matched to a subset of TD participants on age, gender, educational background, and verbal ability. Additional TD participants with a broader range of abilities were also tested. Each participant solved sets of verbal analogies and metaphors in verification formats, allowing measurement of both accuracy and reaction times. Measures of individual differences in vocabulary, verbal working memory, and autistic traits were also obtained. Accuracy for both the verbal analogy and the metaphor task was very similar across the ASD and matched TD groups. However, reaction times on both tasks were longer for the ASD group. Additionally, stronger correlations between verbal analogical reasoning and working memory capacity in the ASD group indicated that processing verbal analogies was more effortful for them. In the case of both groups, accuracy on the metaphor and analogy tasks was correlated. A mediation analysis revealed that after controlling for working memory capacity, the inter-task correlation could be accounted for by the mediating variable of vocabulary knowledge, suggesting that the primary common mechanisms linking the two tasks involve language skills.

The comprehension of grammaticalized implicit meanings in SPCD and ASD children: A comparative study

BACKGROUND

Autism spectrum disorder (ASD) and social pragmatic communication disorder (SPCD) are two neurodevelopmental disorders with many similarities in affected individuals' impairments in social-communicative and pragmatic development. A central question pertaining to their differentiation concerns whether the distinction is truly qualitative or, instead, quantitative in nature, and indeed, defining the boundary between SPCD and ASD with IQ in the normal range often presents differential-diagnostic difficulties. While deficits in the comprehension of certain linguistically systematic implicit verbal meanings have been targeted by experimental research in ASD, to date they have not been investigated in controlled experiments in SPCD.

AIMS

The empirical objectives of our study are twofold. First, it is explored whether the comprehension of a set of highly systematic, grammaticalized implicit meanings is impaired in ASD and SPCD children compared to their typically developing (TD) peers, and whether ASD and SPCD children differ from each other in accessing these verbal meanings. Second, it is investigated whether receptive grammatical competence and first-order ToM abilities are associated with children's performance in any way and whether there is a difference in this regard between the ASD and the SPCD group.

METHODS & PROCEDURES

Our main experiment, using a sentence-picture verification task, tested the comprehension of highly systematic implicit verbal meanings, including grammaticalized implicatures, presuppositions, and entailments. The experiment was complemented with a false-belief (ToM) task and a test of receptive grammar, among other measures. Seventy-one 4-to-9-year-old children participated in the study (ASD: n=19, SPCD: n=13, TD controls: n=39).

OUTCOMES & RESULTS

While both children with SPCD and children with ASD performed significantly more poorly than the TD group, only the comprehension profile of the SPCD group differed significantly from that of the TD group. Importantly, while ASDs' performance exhibited an association with their ToM results, the performance of SPCDs showed a correlation with their receptive grammar skills. By contrast, the performance of TDs correlated with neither.

CONCLUSIONS & IMPLICATIONS

These findings reveal potential divergences in the cognitive developmental mechanisms that underlie the semantic-pragmatic difficulties in the two clinical groups, suggesting that the communicative impairments in ASD and in SPCD differ qualitatively, rather than quantitatively. Specific implications for theories of pragmatic impairments in ASD and in SPCD are discussed.

WHAT THIS PAPER ADDS

What is already known on the subject Linguistically systematic implicit meanings are understudied both in ASD and in SPCD. Within this domain of verbal meaning, the majority of relevant experimental work on ASD, concentrated on generalized (mostly: scalar) implicatures, has yielded somewhat divergent results, while the comprehension difficulties in SPCD have remained barely charted territory. Linguistically more highly conventionalized implicit verbal meanings have not been experimentally investigated in either neurodevelopmental disorder. What this study adds A primary finding of our study is that although both the SPCD and the ASD group show significant deficit in the comprehension of highly conventional, grammaticalized implicit meanings, SPCD children may diverge more in their comprehension profile from their TD peers than ASD children. Another key result is that the comprehension of grammaticalized implicit meanings is linked with different cognitive functions in ASD and in SPCD. While comprehension performance is associated with ToM in ASD but not in SPCD or in TD, it is correlated with receptive grammar skills in SPCD but not in ASD or in TD. Clinical implications of this study These findings provide potential support for the hypothesis that the difference between ASD and SPCD is qualitative rather than quantitative in nature, thereby casting doubt on the conception that pragmatic limitations in SPCD are to be approached as a less severe form of similar deficits in ASD. Uncovering differences in the underlying cognitive sources and in the comprehension deficits of children with ASD and SPCD are critical for the improvement of the accuracy of SPCD children's early diagnosis and timely therapeutic intervention.

Understanding indirect requests for information in high-functioning autism

Few works have addressed the processing of indirect requests in High-Functioning Autism (HFA), and results are conflicting. Some studies report HFA individuals’ difficulties in indirect requests comprehension; others suggest that it might be preserved in HFA. Furthermore, the role of Theory of Mind in understanding indirect requests is an open issue. The goal of this work is twofold: first, assessing whether comprehension of indirect requests for information is preserved in HFA; second, exploring whether mind-reading skills predict this ability. We tested a group of (n = 14; 9–12 years) HFA children and two groups of younger (n = 19; 5–6 years) and older (n = 28; 9–12 years) typically developing (TD) children in a semi-structured task involving direct, indirect and highly indirect requests for information. Results suggested that HFA can understand indirect and highly indirect requests, as well as TD children. Yet, while Theory of Mind skills seem to enhance older TD children understanding, this is not the case for HFA children. Therefore, interestingly, they could rely on different interpretative strategies.

The Role of Working Memory in the Processing of Scalar Implicatures of Patients With Schizophrenia Spectrum and Other Psychotic Disorders

A number of studies have demonstrated pragmatic language difficulties in people with Schizophrenia Spectrum and Other Psychotic Disorders. However, research about how people with schizophrenia spectrum and other psychotic disorders understand scalar implicatures (SIs) is surprisingly rare, since SIs have generated much of the most recent literature. Scalar implicatures are pragmatic inferences, based on linguistic expressions like some, must, or, which are part of a scale of informativeness (e.g., some/many/all). Logically, the less informative expressions imply the more informative ones, but pragmatically people usually infer that the presence of a less informative term implies that the more informative term was not applicable. In one of the few existing studies with people with schizophrenia spectrum and other psychotic disorders, Wampers et al. (2018) observed that in general, people with schizophrenia spectrum and other psychotic disorders were less likely to derive SIs than controls. The current study has three main aims. First, we want to replicate the original finding with the scalar terms some-all. Second, we want to investigate how these patients deal with different scalar terms, that is, we want to investigate if scalar diversity is also observed in this clinical group. Third, we investigate the role of working memory, often seen as another important mechanism to enable inferring SIs. Twenty-one individuals with a psychotic disorder and 21 matched controls answered 54 under-informative statements, in which seven different pairs of scalar terms were used. In addition, working memory capacity was measured. Patients with schizophrenia spectrum and other psychotic disorders did not make more logical interpretations when processing quantifiers, disconfirming Wampers et al. (2018). However, certain scalar scales elicited more pragmatic interpretations than others, which is in line with the scalar diversity hypothesis. Additionally, we observed only partial evidence for the role of working memory. Only for the scalar scale and-or, a significant effect of working memory was observed. The implications of these results for patients with schizophrenia spectrum and other psychotic disorders are discussed, but also the role of working memory for pragmatic inferences, as well as the place of SIs in experimental pragmatics.

Ad-hoc and scalar implicatures in children with autism spectrum disorder

BACKGROUND

Previous studies found that people with Autism Spectrum Disorder (ASD) perform well on pragmatic inference tests that require the use of the linguistic scale <some, all>. The present study extends previous research by testing two types of implicature: scalar implicatures, based on lexical scales, and ad-hoc implicatures, based on contextual scales.

METHODS

We tested 26 children with ASD aged 4-10 years (mean age 7.1) and 26 typically developing (TD) children - matched on chronological age and with a similar performance in non-verbal IQ and vocabulary - by means of a picture selection task for scalar and ad-hoc implicatures. We also investigated the effect of children's scores in standardized tests measuring non-verbal intelligence, lexical, and morphosyntactic abilities and Theory-of-Mind skills on their performance in the implicature tasks.

RESULTS

Although more than half of the children with ASD performed above chance on both kinds of implicatures, their performance as a group was significantly lower than the performance of their TD peers. General cognitive abilities were found to affect the performance of children with ASD on both kinds of implicatures, and Theory-of-Mind reasoning skills were found to be linked to their performance on scalar, but not ad-hoc implicatures.

CONCLUSIONS

We show that children with ASD have difficulty with both kinds of implicatures. These findings may have implications for explanatory theories of pragmatics as well as for clinical work with children with ASD.

Scalar and ad-hoc pragmatic inferences in children: guess which one is easier

Several studies investigated preschoolers' ability to compute scalar and ad-hoc implicatures, but only one compared children's performance with both kinds of implicature with the same task, a picture selection task. In Experiment 1 (N = 58, age: 4;2-6;0), we first show that the truth value judgment task, traditionally employed to investigate children's pragmatic ability, prompts a rate of pragmatic responses comparable to the picture selection task. In Experiment 2 (N = 141, age: 3;8-9;2) we used the picture selection task to compare scalar and ad-hoc implicatures and linked the ability to derive these implicatures to some cognitive and linguistic measures. We found that four- and five-year-olds children performed better on ad-hoc than on scalar implicatures. Furthermore, we found that morphosyntactic competence was associated with success in both kinds of implicatures, while performance on mental state reasoning was positively associated with success on scalar but not ad-hoc implicatures.

The Role of Executive Function and Theory of Mind in Pragmatic Computations

In sentences such as "Some dogs are mammals," the literal semantic meaning ("Some and possibly all dogs are mammals") conflicts with the pragmatic meaning ("Not all dogs are mammals," known as a scalar implicature). Prior work has shown that adults vary widely in the extent to which they adopt the semantic or pragmatic meaning of such utterances, yet the underlying reason for this variation is unknown. Drawing on theoretical models of scalar implicature derivation, we explore the hypothesis that the cognitive abilities of executive function (EF) and theory of mind (ToM) contribute to this observed variation. In Experiment 1, we show that individuals with better ToM are more likely to compute a scalar implicature and adopt the pragmatic meaning of an utterance; however, EF makes no unique contribution to scalar implicature comprehension after accounting for ToM. In Experiment 2, we replicate this finding and assess whether it generalizes to the comprehension of other pragmatic phenomena such as indirect requests (e.g., "It's hot in here" uttered to ask for something to be done) and metaphor (e.g., "to harvest courage"). This is the first evidence that differences in ToM are associated with pragmatic competence in neurotypical adults across distinct pragmatic phenomena.

Complex Inferential Processes Are Needed for Implicature Comprehension, but Not for Implicature Production

Upon hearing “Some of Michelangelo’s sculptures are in Rome,” adults can easily generate a scalar implicature and infer that the intended meaning of the utterance corresponds to “Some but not all Michelangelo’s sculptures are in Rome.” Comprehension experiments show that preschoolers struggle with this kind of inference until at least 5 years of age. Surprisingly, the few studies having investigated children’s production of scalar expressions like some and all suggest that production is adult-like already in their third year of life. Thus, children’s production of implicatures seems to develop at least 2 years before their comprehension of implicatures. In this paper, we present a novel account of scalar implicature generation in the framework of Bidirectional Optimality Theory: the Asymmetry Account. We show that the production–comprehension asymmetry is predicted to emerge because the comprehension of some requires the hearer to consider the speaker’s perspective, but the production of some does not require the speaker to consider the hearer’s perspective. Hence, children’s comprehension of scalar expressions, but not their production of scalar expressions, is predicted to be related to their theory of mind development. Not possessing fully developed theory of mind abilities yet, children thus have difficulty in comprehending scalar expressions such as some in an adult-like way. Our account also explains why variable performance is found in experimental studies testing children’s ability to generate scalar implicatures; moreover, it describes the differences between children’s and adults’ implicature generation in terms of their ability to recursively apply theory of mind; finally, it sheds new light on the question why the interpretation of numerals does not require implicature generation.

Verbal and Figural Creativity in Children With Autism Spectrum Disorder and Typical Development

Previous studies have shown that individuals with autism spectrum disorder (ASD) demonstrate lower performance on creativity tasks. Yet, recent findings suggest that individuals with ASD are not necessarily impaired in verbal creativity, as measured by the novel metaphor generation task. The current study investigates verbal and figural creativity in 40 children with ASD (aged 11–14 years) and 39 peers with typical development (TD) (aged 11–15 years). We also tested the contribution of executive functions to the creative performance. A sentence completion questionnaire was used to test creative verbal generation, while a task of drawing non-existent objects was used to assess figural abilities. The results indicate that children with ASD generated a greater quantity of creative metaphors and showed greater use of a specific kind of representational change on the figural creativity task: cross-category insertions (e.g., a house with a tail). However, no correlation was found between the metaphor generation task and the use of cross-category insertions for either group. Results also showed that, whereas phonemic fluency contributed to the explained variance in novel metaphor generation in the ASD group, fluid intelligence, although only marginally, contributed to variance in novel metaphor generation in the TD group. These findings suggest that verbal creativity and figural creativity are two separate abilities relying on different cognitive resources. Our results show that those with ASD and TD differ in the cognitive abilities they use to perform the metaphor generation task. The research points to a unique creative cognition profile among children with ASD.

Development of Quantitative and Temporal Scalar Implicatures in a Felicity Judgment Task

Experimental investigations into children's interpretation of scalar terms show that children have difficulties with scalar implicatures in tasks. In contrast with adults, they are for instance not able to derive the pragmatic interpretation that "some" means "not all" (Noveck, 2001; Papafragou and Musolino, 2003). However, there is also substantial experimental evidence that children are not incapable of drawing scalar inferences and that they are aware of the pragmatic potential of scalar expressions. In these kinds of studies, the prime interest is to discover what conditions facilitate implicature production for children. One of the factors that seem to be difficult for children is the generation of the scalar alternative. In a Felicity Judgment Task (FJT) the alternative is given. Participants are presented with a pair of utterances and asked to choose the most felicitous description. In such a task, even 5-year-old children are reported to show a very good performance. Our study wants to build on this tradition, by using a FJT where not only "some-all" choices are given, but also "some-many" and "many-all." In combination with a manipulation of the number of successes/failures in the stories, this enabled us to construct control, critical and ambiguous items. We compared the performance of 59 5-year-old children with that of 34 11-year-old children. The results indicated that performance of both age groups was clearly above chance, replicating previous findings. However, for the 5-year-old children, the critical and ambiguous items were more difficult than the control items and they also performed worse on these two types of items than the 11-year-old children. Interestingly with respect to the issue of scalar diversity, the 11-year-old children were also presented temporal items, which turned out to be more difficult than the quantitative ones.