Adult stuttering prevalence I: Systematic review and identification of stuttering in large populations.

Purpose: Stuttering epidemiology is reviewed with a primary goal of appraising methods used to identify stuttering in large populations. Secondary goals were to establish a best estimate of adult stuttering prevalence; identify data that could subgroup stuttering based upon childhood versus adult onset and covert versus over behaviour; and conduct a preliminary assessment of the degree to which stuttering features as a co-occurring diagnosis.

Methods: Systematic review followed PRISMA guidelines.

Adult stuttering prevalence II: Recalculation, subgrouping and estimate of stuttering community engagement.

Purpose: Epidemiological research of stuttering has frequently focused on children, with a relative paucity of population level data specific to adults. Prevalence data for adults are reassessed here, including a breakdown of whether stuttering is overt or covert, and whether onset was in childhood or adulthood. The engagement of adults who stutter with stuttering communities is also estimated.

Give some, keep some, put some: The language of sharing in children.

Sensitivity to linguistic cues, in theory, can change the interpretation of social and game theoretical behavior. We tested this in a pair of experiments with children aged 4 and 5 years. Children were asked to give some, keep some, or put some stickers for themselves or for another player (a puppet) after collaborative activities.

The Knowledge of Autism Questionnaire-UK: Development and Initial Psychometric Evaluation.

Tools to measure autism knowledge are needed to assess levels of understanding within particular groups of people and to evaluate whether awareness-raising campaigns or interventions lead to improvements in understanding. Several such measures are in circulation, but, to our knowledge, there are no psychometrically-validated questionnaires that assess contemporary autism knowledge suitable to the UK context. We aimed to produce a brief measure to assess between-respondent variability and within-respondent change over time.

The Competition Between Processing and Discourse-Pragmatic Factors in Children's and Adults' Production of Adverbial -Clauses.

Purpose: This is the first study to investigate the combined effects of processing-based factors (i.e., clause length and clause order) and discourse-pragmatic factors (i.

The acquisition of English modal constructions: a corpus-based analysis.

The English modal system is complex, exhibiting many-to-one, and one-to-many, form-function mappings. Usage-based approaches emphasise the role of the input in acquisition but rarely address the impact of form-function mappings on acquisition. To test whether consistent form-function mappings facilitate acquisition, we analysed two dense mother-child corpora at age 3 and 4.

Weak Vestibular Response in Persistent Developmental Stuttering.

Vibrational energy created at the larynx during speech will deflect vestibular mechanoreceptors in humans (Todd et al., 2008; Curthoys, 2017; Curthoys et al., 2019).

Structural and interactional aspects of adverbial sentences in English mother-child interactions: an analysis of two dense corpora.

We analysed both structural and functional aspects of sentences containing the four adverbials "after", "before", "because", and "if" in two dense corpora of parent-child interactions from two British English-acquiring children (2;00-4;07). In comparing mothers' and children's usage we separate out the effects of frequency, cognitive complexity and pragmatics in explaining the course of acquisition of adverbial sentences. We also compare these usage patterns to stimuli used in a range of experimental studies and show how differences may account for some of the difficulties that children have shown in experiments.

A Cross-Cultural Analysis of Early Prelinguistic Gesture Development and Its Relationship to Language Development.

Many Western industrialized nations have high levels of ethnic diversity but to date there are very few studies which investigate prelinguistic and early language development in infants from ethnic minority backgrounds. This study tracked the development of infant communicative gestures from 10 to 12 months (n = 59) in three culturally distinct groups in the United Kingdom and measured their relationship, along with maternal utterance frequency and responsiveness, to vocabulary development at 12 and 18 months. No significant differences were found in infant gesture development and maternal responsiveness across the groups, but relationships were identified between gesture, maternal responsiveness, and vocabulary development.

The Role of Animacy in Children's Interpretation of Relative Clauses in English: Evidence From Sentence-Picture Matching and Eye Movements.

Subject relative clauses (SRCs) are typically processed more easily than object relative clauses (ORCs), but this difference is diminished by an inanimate head-noun in semantically non-reversible ORCs ("The book that the boy is reading"). In two eye-tracking experiments, we investigated the influence of animacy on online processing of semantically reversible SRCs and ORCs using lexically inanimate items that were perceptually animate due to motion (e.g.

Interactions between givenness and clause order in children's processing of complex sentences.

Understanding complex sentences that contain multiple clauses referring to events in the world and the relations between them is an important development in children's language learning. A number of theoretical positions have suggested that factors like syntactic structure (clause order), iconicity (whether the order of clauses reflects the order of events), and givenness (whether information is shared between speakers) affect ease of comprehension. We tested these accounts by investigating how these factors interact in British English-speaking children's comprehension of complex sentences with adverbial clauses (after, before, because, if), while controlling for language level, working memory and inhibitory control.

How the input shapes the acquisition of verb morphology: Elicited production and computational modelling in two highly inflected languages.

The aim of the present work was to develop a computational model of how children acquire inflectional morphology for marking person and number; one of the central challenges in language development. First, in order to establish which putative learning phenomena are sufficiently robust to constitute a target for modelling, we ran large-scale elicited production studies with native learners of Finnish (N = 77; 35-63 months) and Polish (N = 81; 35-59 months), using a novel method that, unlike previous studies, allows for elicitation of all six person/number forms in the paradigm (first, second and third person; singular and plural). We then proceeded to build and test a connectionist model of the acquisition of person/number marking which not only acquires near adult-like mastery of the system (including generalisation to unseen items), but also yields all of the key phenomena observed in the elicited-production studies; specifically, effects of token frequency and phonological neighbourhood density of the target form, and a pattern whereby errors generally reflect the replacement of low frequency targets by higher-frequency forms of the same verb, or forms with the same person/number as the target, but with a suffix from an inappropriate conjugation class.

Some Pieces Are Missing: Implicature Production in Children.

Until at least 4 years of age, children, unlike adults, interpret as compatible with . The inability to draw the pragmatic inference leading to interpret as , could be taken to indicate a delay in pragmatic abilities, despite evidence of other early pragmatic skills. However, little is known about how the production of these implicature develops.

Children's Acquisition of the English Past-Tense: Evidence for a Single-Route Account From Novel Verb Production Data.

This study adjudicates between two opposing accounts of morphological productivity, using English past-tense as its test case. The single-route model (e.g.

The Effects of Animacy and Syntax on Priming: A Developmental Study.

Sentence production relies on the activation of semantic information (e.g., noun animacy) and syntactic frames that specify an order for grammatical functions (e.

Iconicity affects children's comprehension of complex sentences: The role of semantics, clause order, input and individual differences.

Complex sentences involving adverbial clauses appear in children's speech at about three years of age yet children have difficulty comprehending these sentences well into the school years. To date, the reasons for these difficulties are unclear, largely because previous studies have tended to focus on only sub-types of adverbial clauses, or have tested only limited theoretical models. In this paper, we provide the most comprehensive experimental study to date.

Keeping it simple: the grammatical properties of shared book reading.

The positive effects of shared book reading on vocabulary and reading development are well attested (e.g., Bus, van Ijzendoorn, & Pellegrini, 1995).

Multiunit Sequences in First Language Acquisition.

Theoretical and empirical reasons suggest that children build their language not only out of individual words but also out of multiunit strings. These are the basis for the development of schemas containing slots. The slots are putative categories that build in abstraction while the schemas eventually connect to other schemas in terms of both meaning and form.

Can Infinitival to Omissions and Provisions Be Primed? An Experimental Investigation Into the Role of Constructional Competition in Infinitival to Omission Errors.

An experimental study was conducted on children aged 2;6-3;0 and 3;6-4;0 investigating the priming effect of two WANT-constructions to establish whether constructional competition contributes to English-speaking children's infinitival to omission errors (e.g., *I want ___ jump now).

Children's understanding of first- and third-person perspectives in complement clauses and false-belief tasks.

De Villiers (Lingua, 2007, Vol. 117, pp. 1858-1878) and others have claimed that children come to understand false belief as they acquire linguistic constructions for representing a proposition and the speaker's epistemic attitude toward that proposition.

German Children's Use of Word Order and Case Marking to Interpret Simple and Complex Sentences: Testing Differences Between Constructions and Lexical Items.

Children and adults follow cues such as case marking and word order in their assignment of semantic roles in simple transitives (e.g., ).

How do language-specific characteristics affect the acquisition of different relative clause types? Evidence from Finnish.

We report three studies (one corpus, two experimental) that investigated the acquisition of relative clauses (RCs) in Finnish-speaking children. Study 1 found that Finnish children's naturalistic exposure to RCs predominantly consists of non-subject relatives (i.e.

Converging and competing cues in the acquisition of syntactic structures: the conjoined agent intransitive.

In two studies we use a pointing task to explore developmentally the nature of the knowledge that underlies three- and four-year-old children's ability to assign meaning to the intransitive structure. The results suggest that early in development children are sensitive to a first-noun-as-causal-agent cue and animacy cues when interpreting conjoined agent intransitives. The same children, however, do not appear to rely exclusively on the number of nouns as a cue to structure meaning.

Teaching versus enforcing game rules in preschoolers' peer interactions.

Children use normative language in two key contexts: when teaching others and when enforcing social norms. We presented pairs of 3- and 5-year-old peers (N=192) with a sorting game in two experimental conditions (in addition to a third baseline condition). In the teaching condition, one child was knowledgeable, whereas the other child was ignorant and so in need of instruction.