Children's reasoning about the efficiency of others' actions: The development of rational action prediction

The relative efficiency of an action is a central criterion in action control and can be used to predict others' behavior. Yet, it is unclear when the ability to predict on and reason about the efficiency of others' actions develops. In three main and two follow-up studies, 3- to 6-year-old children (n = 242) were confronted with vignettes in which protagonists could take a short (efficient) path or a long path. Children predicted which path the protagonist would take and why the protagonist would take a specific path. The 3-year-olds did not take efficiency into account when making decisions even when there was an explicit goal, the task was simplified and made more salient, and children were questioned after exposure to the agent's action. Four years is a transition age for rational action prediction, and the 5-year-olds reasoned on the efficiency of actions before relying on them to predict others' behavior. Results are discussed within a representational redescription account.

An investigation into the relationship between Quality of pantomime gestures and visuospatial skills

While children with developmental language disorder or Williams syndrome appear to use hand gestures to compensate for specific cognitive and communicative difficulties, they have different cognitive strength-weakness profiles. Their semantic and visuospatial skills potentially affect gesture quality such as iconicity. The present study focuses on untangling the unique contribution of these skills in the quality of gestures. An explicit gesture elicitation task was presented to 25 participants with developmental language disorder between 7 and 10 years of age, 25 age-matched peers with typical development, and 14 participants with Williams Syndrome (8-23 years). They gestured pictures of objects without using speech (pantomime). The iconicity, semantic richness, and representation technique of the pantomimes were coded. Participants' semantic association and visuospatial skills were formally assessed. Iconicity was slightly lower in individuals with Williams syndrome, which seems related to their visuospatial deficit. While semantic saliency was similar across participant groups, small differences in representation technique were found. Partial correlations showed that visuospatial skills and semantic skills were instrumental in producing clear pantomimes. These findings indicate that clinicians aiming to enhance individuals' natural iconic gestures should consider achieved iconicity, particularly in individuals with low visuospatial skills.

Functional fixedness and body-part-as-object production in pantomime

In pantomiming the use of tools, it is possible to use a body part as the object (BPO) or imagine the object (IO). The present four studies test how conceptualizing the functions of objects may underlie BPO production in a non-clinical adult population. We showed that familiar vs. unfamiliar tools (Study 1) and visual experience only vs. visual + motor experience with novel tools (Study 2) made no difference in BPO production. In Study 3, participants showed a trend for higher BPO production for tools presented in two-dimensional pictures rather than in reality. In Study 4, participants' functional fixedness was experimentally manipulated: participants were told unfamiliar tools had either five functions or only one function. Participants produced significantly more BPOs in the one-function condition. These results suggest that conceptualizing objects as having a fixed function is a predictor of BPO production.

Handling or being the concept: An fMRI study on metonymy representations in coverbal gestures

In "Two heads are better than one," "head" stands for people and focuses the message on the intelligence of people. This is an example of figurative language through metonymy, where substituting a whole entity by one of its parts focuses attention on a specific aspect of the entity. Whereas metaphors, another figurative language device, are substitutions based on similarity, metonymy involves substitutions based on associations. Both are figures of speech but are also expressed in coverbal gestures during multimodal communication. The closest neuropsychological studies of metonymy in gestures have been nonlinguistic tool-use, illustrated by the classic apraxic problem of body-part-as-object (BPO, equivalent to an internal metonymy representation of the tool) vs. pantomimed action (external metonymy representation of the absent object/tool). Combining these research domains with concepts in cognitive linguistic research on gestures, we conducted an fMRI study to investigate metonymy resolution in coverbal gestures. Given the greater difficulty in developmental and apraxia studies, perhaps explained by the more complex semantic inferencing involved for external metonymy than for internal metonymy representations, we hypothesized that external metonymy resolution requires greater processing demands and that the neural resources supporting metonymy resolution would modulate regions involved in semantic processing. We found that there are indeed greater activations for external than for internal metonymy resolution in the temporoparietal junction (TPJ). This area is posterior to the lateral temporal regions recruited by metaphor processing. Effective connectivity analysis confirmed our hypothesis that metonymy resolution modulates areas implicated in semantic processing. We interpret our results in an interdisciplinary view of what metonymy in action can reveal about abstract cognition.

Developmental evidence for continuity from action to gesture to sign/word

What is linguistic communication and what is it not? Even if we often convey meanings through visible bodily actions, these are rarely considered part of human language. However, co-verbal gestures have compositional structure and semantic significance, while highly iconic structures are essential in sign languages. This paper offers a review of major studies conducted in our lab on the continuity from actions to gestures to words/signs in development. After a brief introduction, we show how gestures may bridge the gap between actions and words and how this interrelationship extends beyond early childhood and across cultures. We stress the role of sign language and multimodal communication in the study of language as a form of action and present recent research on motoric aspects of human communication. Studying the visible actions of speakers and signers leads to a revision of the traditional dichotomy between linguistic and enacted, and to the development of a new approach to embodied language.

Gesture and Symbolic Representation in Italian and English-Speaking Canadian 2-Year-Olds

Analyses of elicited pantomime, primarily of English-speaking children, show that preschool-aged children are more likely to symbolically represent an object with gestures depicting an object's form rather than its function. In contrast, anecdotal reports of spontaneous gesture production in younger children suggest that children use multiple representational techniques. This study examined the spontaneous gestures of sixty-four 2-year-old Italian children and English-speaking Canadian children, primarily from middle-class Caucasian families. The Italian children produced twice as many gestures as Canadian children in a picture-naming task but produced a similar range of representational techniques. Two-year-olds were equally likely to produce gestures depicting function as form. These data suggest young children's communicative skills are supported by a symbolic capacity that reflects contextual communicative demands.

A meta-analysis of the Dimensional Change Card Sort: Implications for developmental theories and the measurement of executive function in children

The Dimensional Change Card Sort (DCCS) is a widely used measure of executive function in children. In the standard version, children are shown cards depicting objects that vary on two dimensions (e.g., colored shapes such as red rabbits and blue boats), and are told to sort them first by one set of rules (e.g., shape) and then by another (e.g., color). Most 3-year-olds persist in sorting by the pre-switch rules, whereas 5-year-olds switch flexibly. We conducted a meta-analysis of standard and experimental versions of the task (N = 69 reports, 426 conditions) to examine the influence of diverse task variations on performance. Age, how the test stimuli were labeled for the child, emphasis on conflict in the verbal introduction of the post-switch rules, and the number of pre-switch trials each independently predicted switching on the standard DCCS, whereas pre-switch feedback, practice, and task modality did not. Increasing the relative salience of the post-switch dimension was associated with higher rates of switching, and, conversely, decreasing post-switch salience was associated with lower rates of switching, and under both kinds of manipulation performance continued to be associated with age. Spatially separating the dimensional values was associated with higher rates of switching, and it was confirmed that the degree of spatial separation matters, with children benefiting most when the dimensional values are fully spatially segregated. Switch rates tended to be higher in versions on which children were prompted to label the stimuli compared to when the experimenter provided labels, and lower when reversal instructions were used in conjunction with the standard task stimuli. Theoretical and practical implications for the study and measurement of executive function in early childhood are discussed.

NIH Toolbox Cognition Battery (CB): validation of executive function measures in adults

This study describes psychometric properties of the NIH Toolbox Cognition Battery (NIHTB-CB) executive function measures in an adult sample. The NIHTB-CB was designed for use in epidemiologic studies and clinical trials for ages 3 to 85. A total of 268 self-described healthy adults were recruited at four university-based sites, using stratified sampling guidelines to target demographic variability for age (20-85 years), gender, education and ethnicity. The NIHTB-CB contains two computer-based instruments assessing executive function: the Dimensional Change Card Sort (a measure of cognitive flexibility) and a flanker task (a measure of inhibitory control and selective attention). Participants completed the NIHTB-CB, corresponding gold standard convergent and discriminant measures, and sociodemographic questionnaires. A subset of participants (N=89) was retested 7 to 21 days later. Results reveal excellent sensitivity to age-related changes during adulthood, excellent test-retest reliability, and adequate to good convergent and discriminant validity. The NIH Toolbox EF measures can be used effectively in epidemiologic and clinical studies.

The role of distancing in Werner and Kaplan’s account of symbol formation and beyond

The concept of distancing or polarization plays a central role in Werner and Kaplan’s account of symbol formation. It refers to the process of progressive differentiation and hierarchic integration of the four components constitutive of symbolic activity: addressor, addressee, symbolic vehicle and referent. Specifically, Werner and Kaplan suggest that distancing takes place between person and referent, between person and symbolic vehicle, between symbolic vehicle and referent and between addressor and addressee. We describe the theoretical context and different aspects of the distancing process. Furthermore, we argue that the distancing process identifies central prerequisites of symbolic activity that are largely ignored by contemporary developmental theories. We demonstrate the different aspects of the distancing process in several domains of symbolic development, including words, gestural development and pretend play. Finally, we compare Werner and Kaplan’s concept of distancing to ideas of distancing developed in recent developmental theories.

N2 amplitude as a neural marker of executive function in young children: an ERP study of children who switch versus perseverate on the Dimensional Change Card Sort

To explore the neurocognitive mechanisms underlying individual differences in executive function during the preschool years, high-density electroencephalography (EEG) was used to record event-related potentials (ERPs) from 99 children (between 35 and 54 months of age) during performance on the Dimensional Change Card Sort (DCCS), a widely used measure of executive function in which participants are required to sort bivalent stimuli first by one dimension and then by another. ERP analyses comparing children who switched flexibly (passed) to those who perseverated on post-switch trials (failed) focused on the N2 component, which was maximal over fronto-central sites. N2 amplitude was smaller (less negative) for children who passed the DCCS than for children who failed, suggesting that the N2, often associated with conflict monitoring, may serve as a neural marker of individual differences in executive function. Implications for learning and education are discussed.

Gesture in the developing brain

Speakers convey meaning not only through words, but also through gestures. Although children are exposed to co-speech gestures from birth, we do not know how the developing brain comes to connect meaning conveyed in gesture with speech. We used functional magnetic resonance imaging (fMRI) to address this question and scanned 8- to 11-year-old children and adults listening to stories accompanied by hand movements, either meaningful co-speech gestures or meaningless self-adaptors. When listening to stories accompanied by both types of hand movement, both children and adults recruited inferior frontal, inferior parietal, and posterior temporal brain regions known to be involved in processing language not accompanied by hand movements. There were, however, age-related differences in activity in posterior superior temporal sulcus (STSp), inferior frontal gyrus, pars triangularis (IFGTr), and posterior middle temporal gyrus (MTGp) regions previously implicated in processing gesture. Both children and adults showed sensitivity to the meaning of hand movements in IFGTr and MTGp, but in different ways. Finally, we found that hand movement meaning modulates interactions between STSp and other posterior temporal and inferior parietal regions for adults, but not for children. These results shed light on the developing neural substrate for understanding meaning contributed by co-speech gesture.

The Dimensional Change Card Sort (DCCS): a method of assessing executive function in children

The dimensional change card sort (DCCS) is an easily administered and widely used measure of executive function that is suitable for use with participants across a wide range of ages. In the standard version, children are required to sort a series of bivalent test cards, first according to one dimension (e.g., color), and then according to the other (e.g., shape). Most 3-year-olds perseverate during the post-switch phase, exhibiting a pattern of inflexibility similar to that seen in patients with prefrontal cortical damage. By 5 years of age, most children switch when instructed to do so. Performance on the DCCS provides an index of the development of executive function, and it is impaired in children with disorders such as attention-deficit/hyperactivity disorder (ADHD) and autism. We describe the protocol for the standard version (duration = 5 min) and the more challenging border version (duration = 5 min), which may be used with children as old as 7 years.