Case report: selective deficit in the production of intransitive gestures in an individual with autism

Visuo-spatial complexity potentiates the body-part effect in intransitive imitation of meaningless gestures

Recent studies on the imitation of intransitive gestures suggest that the body part effect relies mainly upon the direct route of the dual-route model through a visuo-transformation mechanism. Here, we test the visuo-constructive hypothesis which posits that the visual complexity may directly potentiate the body part effect for meaningless gestures. We predicted that the difference between imitation of hand and finger gestures would increase with the visuo-spatial complexity of gestures. Second, we aimed to identify some of the visuo-spatial predictors of meaningless finger imitation skills. Thirty-eight participants underwent an imitation task containing three distinct set of gestures, that is, meaningful gestures, meaningless gestures with low visual complexity, and meaningless gestures with higher visual complexity than the first set of meaningless gestures. Our results were in general agreement with the visuo-constructive hypothesis, showing an increase in the difference between hand and finger gestures, but only for meaningless gestures with higher visuo-spatial complexity. Regression analyses confirm that imitation accuracy decreases with resource-demanding visuo-spatial factors. Taken together, our results suggest that the body part effect is highly dependent on the visuo-spatial characteristics of the gestures.

The neural correlates of limb apraxia: An anatomical likelihood estimation meta-analysis of lesion-symptom mapping studies in brain-damaged patients

Limb apraxia is a motor disorder frequently observed following a stroke. Apraxic deficits are classically assessed with four tasks: tool use, pantomime of tool use, imitation, and gesture understanding. These tasks are supported by several cognitive processes represented in a left-lateralized brain network including inferior frontal gyrus, inferior parietal lobe (IPL), and lateral occipito-temporal cortex (LOTC). For the past twenty years, voxel-wise lesion symptom mapping (VLSM) studies have been used to unravel the neural correlates associated with apraxia, but none of them has proposed a comprehensive view of the topic. In the present work, we proposed to fill this gap by performing a systematic Anatomic Likelihood Estimation meta-analysis of VLSM studies which included tasks traditionally used to assess apraxia. We found that the IPL was crucial for all the tasks. Moreover, lesions within the LOTC were more associated with imitation deficits than tool use or pantomime, confirming its important role in higher visual processing. Our results questioned traditional neurocognitive models on apraxia and may have important clinical implications.

Interactive mirrOring Games wIth sOCial rObot (IOGIOCO): a pilot study on the use of intransitive gestures in a sample of Italian preschool children with autism spectrum disorder

Background

Autism Spectrum Disorder (ASD) is a neurodevelopmental disorder characterized by persistent deficits in social communication, social interaction, and restricted behaviors. The importance of early intervention has been widely demonstrated, and developmental trajectories in ASD emphasize the importance of nonverbal communication, such as intransitive gesture production, as a possible positive prognostic factor for language development. The use of technological tools in the therapy of individuals with ASD has also become increasingly important due to their higher engagement and responsiveness to technological objects, such as robots.

Materials and methods

We developed a training protocol using the humanoid robot NAO, called IOGIOCO (Interactive mirroring Games wIth sOCial rObot), based on the use of intransitive gestures embedded in naturalistic dialogues, stimulating a triadic interaction between child, robot and therapist. The training was divided into six levels; the first 2 levels were called "familiarization levels," and the other 4 were "training levels". The technological setup includes different complexity levels, from mirroring tasks to building spontaneous interactions. We tested the protocol on 10 preschool children with ASD (aged 2-6 years) for 14 weeks. We assessed them at recruitment (T0), at the end of training (T1), and after 6 months (T2).

Results

We demonstrated the tolerability of the protocol. We found that one group (n=4, males and 2 females) reached the training level, while another and group (n=6 males) remained at a familiarization level (mirroring), we analyzed the results for the two groups. In the group that reached the training levels, we found promising results, such as an improvement in the Social Adaptive Domain of the ABAS-II questionnaire between T0 and T2.

Conclusion

While current results will need a Randomized Controlled Trial to be confirmed, the present work sets an important milestone in using social robots for ASD treatment, aimed at impacting social and communication skills in everyday life.

The Neurocognitive Bases of Meaningful Intransitive Gestures: A Systematic Review and Meta-analysis of Neuropsychological Studies

Researchers and clinicians have long used meaningful intransitive (i.e., not tool-related; MFI) gestures to assess apraxia-a complex and frequent motor-cognitive disorder. Nevertheless, the neurocognitive bases of these gestures remain incompletely understood. Models of apraxia have assumed that meaningful intransitive gestures depend on either long-term memory (i.e., semantic memory and action lexicons) stored in the left hemisphere, or social cognition and the right hemisphere. This meta-analysis of 42 studies reports the performance of 2659 patients with either left or right hemisphere damage in tests of meaningful intransitive gestures, as compared to other gestures (i.e., MFT or meaningful transitive and MLI or meaningless intransitive) and cognitive tests. The key findings are as follows: (1) deficits of meaningful intransitive gestures are more frequent and severe after left than right hemisphere lesions, but they have been reported in both groups; (2) we found a transitivity effect in patients with lesions of the left hemisphere (i.e., meaningful transitive gestures more difficult than meaningful intransitive gestures) but a "reverse" transitivity effect in patients with lesions of the right hemisphere (i.e., meaningful transitive gestures easier than meaningful intransitive gestures); (3) there is a strong association between meaningful intransitive and transitive (but not meaningless) gestures; (4) isolated deficits of meaningful intransitive gestures are more frequent in cases with right than left hemisphere lesions; (5) these deficits may occur in the absence of language and semantic memory impairments; (6) meaningful intransitive gesture performance seems to vary according to the emotional content of gestures (i.e., body-centered gestures and emotional valence-intensity). These findings are partially consistent with the social cognition hypothesis. Methodological recommendations are given for future studies.

A fist bump in a political meeting? The influence of social context on affordance selection

Historically, understanding human cognition such as action processing has been a challenging issue in cognitive neuropsychology and the more we know about cognition, the more we shape it as a complex, multi-determined phenomenon that is embedded in a social context. The present study aimed at understanding how the social context could influence affordance selection. We hypothesized that affordance selection would be modulated by social context and that a given hand configuration would be considered appropriate or not, as a function of the presence or absence of social context. Twenty-six healthy participants were asked to judge the appropriateness of three variants of 10 hand-object interactions based on photographs presented with or without a visual, social context. In our results, hand configurations were intrinsically acceptable or not, but this effect was modulated by the social context. A three-step model of the influence of social context on affordance selection was proposed, according to which selection depends on social norms, in the form of social knowledge and social context analysis.

Gestures convey different physiological responses when performed toward and away from the body

We assessed the sympathetic and parasympathetic activation associated to the observation of Pantomime (i.e. the mime of the use of a tool) and Intransitive gestures (i.e. expressive) performed toward (e.g. a comb and “thinking”) and away from the body (e.g. key and “come here”) in a group of healthy participants while both pupil dilation (N = 31) and heart rate variability (N = 33; HF-HRV) were recorded. Large pupil dilation was observed in both Pantomime and Intransitive gestures toward the body; whereas an increase of the vagal suppression was observed in Intransitive gestures away from the body but not in those toward the body. Our results suggest that the space where people act when performing a gesture has an impact on the physiological responses of the observer in relation to the type of social communicative information that the gesture direction conveys, from a more intimate (toward the body) to a more interactive one (away from the body).

Who is a better teacher for children with autism? Comparison of learning outcomes between robot-based and human-based interventions in gestural production and recognition

BACKGROUND

Individuals with autism spectrum disorder (ASD) tend to show deficits in engaging with humans. Previous findings have shown that robot-based training improves the gestural recognition and production of children with ASD. It is not known whether social robots perform better than human therapists in teaching children with ASD.

AIMS

The present study aims to compare the learning outcomes in children with ASD and intellectual disabilities from robot-based intervention on gestural use to those from human-based intervention.

METHODS AND PROCEDURES

Children aged six to 12 with low-functioning autism were randomly assigned to the robot group (N = 12) and human group (N = 11). In both groups, human experimenters or social robots engaged in daily life conversations and demonstrated to children 14 intransitive gestures in a highly-structured and standardized intervention protocol.

OUTCOMES AND RESULTS

Children with ASD in the human group were as likely to recognize gestures and produce them accurately as those in the robot group in both training and new conversations. Their learning outcomes maintained for at least two weeks.

CONCLUSIONS AND IMPLICATIONS

The social cues found in the human-based intervention might not influence gestural learning. It does not matter who serves as teaching agents when the lessons are highly structured.

Robot-based intervention may reduce delay in the production of intransitive gestures in Chinese-speaking preschoolers with autism spectrum disorder

Background

Past studies have shown that robot-based intervention was effective in improving gestural use in children with autism spectrum disorders (ASD). The present study examined whether children with ASD could catch up to the level of gestural production found in age-matched children with typical development and whether they showed an increase in verbal imitation after the completion of robot-based training. We also explored the cognitive and motor skills associated with gestural learning.

Methods

Children with ASD were randomly assigned to two groups. Four- to 6-year-old children with ASD in the intervention group (N = 15) received four 30-min robot-based gestural training sessions. In each session, a social robot, NAO, narrated five stories and gestured (e.g., both hands clapping for an awesome expression). Children with ASD were told to imitate the gestures during training. Age-matched children with ASD in the wait-list control group (N = 15) and age-matched children with typical development (N = 15) received the gestural training after the completion of research. Standardized pretests and posttests (both immediate and delayed) were administered to assess the accuracy and appropriateness of gestural production in both training and novel stories. Children's language and communication abilities, gestural recognition skills, fine motor proficiencies, and attention skills were also examined.

Results

Children with ASD in the intervention condition were more likely to produce accurate or appropriate intransitive gestures in training and novel stories than those in the wait-list control. The positive learning outcomes were maintained in the delayed posttests. The level of gestural production accuracy in children with ASD in the delayed posttest of novel stories was comparable to that in children with typical development, suggesting that children with ASD could catch up to the level of gestural production found in children with typical development. Children with ASD in the intervention condition were also more likely to produce verbal markers while gesturing than those in the wait-list control. Gestural recognition skills were found to significantly predict the learning of gestural production accuracy in the children with ASD, with such relation partially mediated via spontaneous imitation.

Conclusions

Robot-based intervention may reduce the gestural delay in children with ASD in their early childhood.

Dyspraxia in ASD: Impaired coordination of movement elements

Children with autism spectrum disorders (ASD) have long been known to have deficits in the performance of praxis gestures; these motor deficits also correlate with social and communicative deficits. To date, the precise nature of the errors involved in praxis has not been clearly mapped out. Based on observations of individuals with ASD performing gestures, we hypothesized that the simultaneous execution of multiple movement elements is especially impaired in affected children. We examined 25 school-aged participants with ASD and 25 age-matched controls performing seven simultaneous gestures that required the concurrent performance of movement elements and nine serial gestures, in which all elements were performed serially. There was indeed a group × gesture-type interaction (P < 0.001). Whereas both groups had greater difficulty performing simultaneous than serial gestures, children with ASD had a 2.6-times greater performance decrement with simultaneous (vs. serial) gestures than controls. These results point to a potential deficit in the simultaneous processing of multiple inputs and outputs in ASD. Such deficits could relate to models of social interaction that highlight the parallel-processing nature of social communication. Autism Res 2016,. © 2016 International Society for Autism Research, Wiley Periodicals, Inc. Autism Res 2017, 10: 648-652. © 2016 International Society for Autism Research, Wiley Periodicals, Inc.

The use of hand gestures to communicate about nonpresent objects in mind among children with autism spectrum disorder

PURPOSE

The current study examined whether children with autism spectrum disorder (ASD), in comparison with typically developing children, perceive and produce gestures to identify nonpresent objects (i.e., referent-identifying gestures), which is crucial for communicating ideas in a discourse.

METHOD

An experimenter described the uses of daily-life objects to 6- to 12-year-old children both orally and with gestures. The children were then asked to describe how they performed daily activities using those objects.

RESULTS

All children gestured. A gesture identified a nonpresent referent if it was produced in the same location that had previously been established by the experimenter. Children with ASD gestured at the specific locations less often than typically developing children. Verbal and spatial memory were positively correlated with the ability to produce referent-identifying gestures for all children. However, the positive correlation between Raven's Children Progressive Matrices score and the production of referent-identifying gestures was found only in children with ASD.

CONCLUSIONS

Children with ASD might be less able to perceive and produce referent-identifying gestures and may rely more heavily on visual-spatial skills in producing referent-identifying gestures. The results have clinical implications for designing an intervention program to enhance the ability of children with ASD to communicate about nonpresent objects with gestures.

The development of co-speech gesture and its semantic integration with speech in 6- to 12-year-old children with autism spectrum disorders

Previous work leaves open the question of whether children with autism spectrum disorders aged 6-12 years have delay in producing gestures compared to their typically developing peers. This study examined gestural production among school-aged children in a naturalistic context and how their gestures are semantically related to the accompanying speech. Delay in gestural production was found in children with autism spectrum disorders through their middle to late childhood. Compared to their typically developing counterparts, children with autism spectrum disorders gestured less often and used fewer types of gestures, in particular markers, which carry culture-specific meaning. Typically developing children's gestural production was related to language and cognitive skills, but among children with autism spectrum disorders, gestural production was more strongly related to the severity of socio-communicative impairment. Gesture impairment also included the failure to integrate speech with gesture: in particular, supplementary gestures are absent in children with autism spectrum disorders. The findings extend our understanding of gestural production in school-aged children with autism spectrum disorders during spontaneous interaction. The results can help guide new therapies for gestural production for children with autism spectrum disorders in middle and late childhood.

Parent-child gesture use during problem solving in autistic spectrum disorder

This study examined the relationship between child language skills and parent and child gestures of 58 youths with and without an autism spectrum disorder (ASD) diagnosis. Frequencies and rates of total gesture use as well as five categories of gestures (deictic, conventional, beat, iconic, and metaphoric) were reliably coded during the collaborative Tower of Hanoi task. Children with ASD had lower Peabody Picture Vocabulary Test scores and gestured less and at lower rates compared to typically developing children. Gesture use was unrelated to vocabulary for typically developing children, but positively associated with vocabulary for those with ASD. Demographic correlates of gesturing differed by group. Gesture may be a point of communication intervention for families with children with ASD.

Exploring the Relationship Between Gesture and Language in ASD

In this paper, we will explore the relationship between gesture and language in autism spectrum disorders (ASD). Gesture and speech have been shown to share the same neural substrates, and it has been proposed that speech evolved over time from a gestural repertoire. Simultaneously, research in gesture and language has shown that gesture plays a critical role in language development, and a gestural disturbance may be a predictor of future language development. Individuals with autism often present with imitation deficits, developmental dyspraxia, and deficits in motor coordination. Taken together, these deficits pose challenges to the speech-language pathologist providing therapy to these clients. If gesture is indeed critical to language development, and individuals with ASD demonstrate gestural deficits, new therapies are needed to bridge this gap. We will describe an innovative battery of tasks assessing gesture and discuss future gestural intervention.

Current tests and trends in single-case neuropsychology

In this issue of Cortex, Crawford, Garthwaite and Ryan publish bayesian statistical tests that will enable researchers to take account of covariates when comparing single patients to control samples. In this article, we provide some context for this development, from an audit of the Cortex archives. We suggest that single-case research is alive and well, and more rigorous than ever, and that current practice has been shaped considerably by Crawford and colleagues' statistical refinements over the past 12 years. However, there is scope for further tightening and standardisation of statistical methods and reporting standards. The advantages offered by the new bayesian tests should promote the even wider use of appropriate statistical methods, with benefits for the validity of individual studies, and for cross-comparability in the single-case literature.

Single-case research in neuropsychology: a comparison of five forms of t-test for comparing a case to controls

Five inferential methods employed in single-case studies to compare a case to controls are examined; all of these make use of a t-distribution. It is shown that three of these ostensibly different methods are in fact strictly equivalent and are not fit for purpose; they are associated with grossly inflated Type I errors (these exceed even the error rate obtained when a case's score is converted to a z score and the latter used as a test statistic). When used as significance tests, the two remaining methods (Crawford and Howell's method and a prediction interval method first used by Barton and colleagues) are also equivalent and achieve control of the Type I error rate (the two methods do differ however in other important aspects). A number of broader issues also arise from the present findings, namely: (a) they underline the value of accompanying significance test results with the effect size for the difference between a case and controls, (b) they suggest that less care is often taken over statistical methods than over other aspects of single-case studies, and (c) they indicate that some neuropsychologists have a distorted conception of the nature of hypothesis testing in single-case research (it is argued that this may stem from a failure to distinguish between group studies and single-case studies).

Exploring the relationship between gestural recognition and imitation: evidence of dyspraxia in autism spectrum disorders

In this study, the relationship between gesture recognition and imitation was explored. Nineteen individuals with Autism Spectrum Disorder (ASD) were compared to a control group of 23 typically developing children on their ability to imitate and recognize three gesture types (transitive, intransitive, and pantomimes). The ASD group performed more poorly than controls on all tasks of recognition and imitation. Higher performance on tests of working memory was associated with increased odds of successful imitation in both groups. Group differences remained even when working memory was statistically controlled for. An association was revealed in the ASD group between pantomime recognition and imitation but a similar association was not identified for intransitive gestures suggesting that recognition alone is not sufficient for imitation success.

Altered connectivity and action model formation in autism is autism

Internal action models refer to sensory-motor programs that form the brain basis for a wide range of skilled behavior and for understanding others' actions. Development of these action models, particularly those reliant on visual cues from the external world, depends on connectivity between distant brain regions. Studies of children with autism reveal anomalous patterns of motor learning and impaired execution of skilled motor gestures. These findings robustly correlate with measures of social and communicative function, suggesting that anomalous action model formation may contribute to impaired development of social and communicative (as well as motor) capacity in autism. Examination of the pattern of behavioral findings, as well as convergent data from neuroimaging techniques, further suggests that autism-associated action model formation may be related to abnormalities in neural connectivity, particularly decreased function of long-range connections. This line of study can lead to important advances in understanding the neural basis of autism and, more critically, can be used to guide effective therapies targeted at improving social, communicative, and motor function.