Movement preparation in high-functioning autism and Asperger disorder: a serial choice reaction time task involving motor reprogramming

Far Transfer Effects of Trainings on Executive Functions in Neurodevelopmental Disorders: A Systematic Review and Metanalysis

Executive Functions are a set of interrelated, top-down processes essential for adaptive goal-directed behaviour, frequently impaired across different neurodevelopmental disorders with variable degrees of severity. Many executive-function-training studies in children with neurodevelopmental disorders have focused on near effects, investigating post-treatment improvements on directly trained processes, while enhancements of skills not directly trained, defined as far effects, are less considered, albeit these could be extremely relevant for reducing the negative impact of a disorder's core symptomatology. This systematic review and metanalysis aims to investigate the far effect outcomes after EF training in children with different types of neurodevelopmental disorders. 17 studies met the inclusion criteria for the systematic review, while 15 studies were selected in the metanalysis. An overall statistically significant effect size was found in the majority of far effect outcome measures considered in the studies. In particular, trainings on executive functions determine significant far effects on daily life functioning (0.46, 95% CI: [0.05-0.87]) and clinical symptoms (0.33, 95% CI: [0.15-0.51]). Despite a high variability of the results, intensity, frequency and the laboratory/life contexts dimension seem to be the most influential variables in determining far effects. This systematic review and metanalysis highlights the need to measure far effects of executive function training in neurodevelopmental disorders, selecting treatments not only on directly targeted processes, but also according to far impacts on the functional weakness of the disorder.

Motor deficits in autism differ from that of developmental coordination disorder

LAY ABSTRACT

A vast majority of individuals with autism spectrum disorder experience impairments in motor skills. Those are often labelled as additional developmental coordination disorder despite the lack of studies comparing both disorders. Consequently, motor skills rehabilitation programmes in autism are often not specific but rather consist in standard programmes for developmental coordination disorder. Here, we compared motor performance in three groups of children: a control group, an autism spectrum disorder group and a developmental coordination disorder group. Despite similar level of motor skills evaluated by the standard movement assessment battery for children, in a Reach-to-Displace Task, children with autism spectrum disorder and developmental coordination disorder showed specific motor control deficits. Children with autism spectrum disorder failed to anticipate the object properties, but could correct their movement as well as typically developing children. In contrast, children with developmental coordination disorder were atypically slow, but showed a spared anticipation. Our study has important clinical implications as motor skills rehabilitations are crucial to both populations. Specifically, our findings suggest that individuals with autism spectrum disorder would benefit from therapies aiming at improving their anticipation, maybe through the support of their preserved representations and use of sensory information. Conversely, individuals with developmental coordination disorder would benefit from a focus on the use of sensory information in a timely fashion.

Memory for actions and reality monitoring in adults with autism spectrum disorder

Reality monitoring is the cognitive process of distinguishing between internally and externally generated information sources such as imagined and performed actions. The purpose of this study was to examine self-self-monitoring with action in people with autism, which has not been examined previously, using subject performed tasks along with free recall and recognition. Twenty adults with ASD and 20 adults with typical development (TD) participated in this study. Participants memorized action sentences such as "write in pencil" and "under imagined, pantomime, or enacted conditions." Free recall, yes/no recognition, and reality monitoring tests were conducted immediately after and one week later. There was no difference in reality monitoring between the ASD and TD groups. The free recall and recognition performance of the ASD group was lower than that of the TD group. The results of the present study support the previously reported finding of unimpaired retrospective mechanisms of sense of agency related to reality monitoring in people with ASD. Moreover, low levels of free recall and recognition were discussed regarding difficulties in memory reconstruction and consolidation.

Taking Sides: Asymmetries in the Evolution of Human Brain Development in Better Understanding Autism Spectrum Disorder

Confirmation from structural, functional, and behavioral studies agree and suggest a configuration of atypical lateralization in individuals with autistic spectrum disorders (ASD). It is suggested that patterns of cortical and behavioral atypicality are evident in individuals with ASDs with atypical lateralization being common in individuals with ASDs. The paper endeavors to better understand the relationship between alterations in typical cortical asymmetries and functional lateralization in ASD in evolutionary terms. We have proposed that both early genetic and/or environmental influences can alter the developmental process of cortical lateralization. There invariably is a “chicken or egg” issue that arises whether atypical cortical anatomy associated with abnormal function, or alternatively whether functional atypicality generates abnormal structure.

Autism-spectrum traits in neurotypicals predict the embodiment of manipulation knowledge about object concepts: Evidence from eyetracking

Sensorimotor-based theories of cognition predict that even subtle developmental motor differences, such as those characterizing autism spectrum disorder (ASD), impact how we represent the meaning of manipulable objects (e.g., faucet). Here, we test 85 neurotypical participants, who varied widely on the Adult Autism Spectrum Quotient (AQ), a measure intended to capture variability in ASD characteristics in the general adult population (participant scores were all below the clinical threshold for autism). Participants completed a visual world eyetracking task designed to assess the activation of conceptual representations of manipulable objects. Participants heard words referring to manually manipulable objects (e.g., faucet) while we recorded their eye movements to arrays of four objects: the named object, a related object typically manipulated similarly (e.g., jar), and two unrelated objects. Consistent with prior work, we observed more looks to the related object than to the unrelated ones (i.e., a manipulation-relatedness effect). This effect likely reflects the overlapping conceptual representations of objects sharing manipulation characteristics (e.g., faucet and jar), due to embodied sensorimotor properties being part of their representations. Critically, we observed—among typically developed young adults—that as AQ scores increased, manipulation-relatedness effects decreased. In contrast, in a visual control condition, in which a target object was paired with related objects of a similar shape (e.g., snake and rope), relatedness effects increased with AQ scores. The results show that AQ scores can predict variation in how object-concept representations are activated for typically developed individuals. More speculatively, they are consistent with the hypothesis that in individuals with ASD, differences in object-concept representations emerge at least in part via differences in sensorimotor experience.

Attention Deficits Influence the Development of Motor Abnormalities in High Functioning Autism

Early attentional dysfunction is one of the most consistent findings in autism spectrum disorder (ASD), including the high functioning autism (HFA). There are no studies that assess how the atypical attentional processes affect the motor functioning in HFA. In this study, we evaluated attentional and motor functioning in a sample of 15 drug-naive patients with HFA and 15 healthy children (HC), and possible link between attentional dysfunction and motor impairment in HFA. Compared to HC, HFA group was seriously impaired in a considerable number of attentional processes and showed a greater number of motor abnormalities. Significant correlations between attention deficits and motor abnormalities were observed in HFA group. These preliminary findings suggest that deficit of attentional processes can be implied in motor abnormalities in HFA.

Intact predictive motor sequence learning in autism spectrum disorder

Atypical motor learning has been suggested to underpin the development of motoric challenges (e.g., handwriting difficulties) in autism. Bayesian accounts of autistic cognition propose a mechanistic explanation for differences in the learning process in autism. Specifically, that autistic individuals overweight incoming, at the expense of prior, information and are thus less likely to (a) build stable expectations of upcoming events and (b) react to statistically surprising events. Although Bayesian accounts have been suggested to explain differences in learning across a range of domains, to date, such accounts have not been extended to motor learning. 28 autistic and 35 non-autistic controls (IQ > 70) completed a computerised task in which they learned sequences of actions. On occasional "surprising" trials, an expected action had to be replaced with an unexpected action. Sequence learning was indexed as the reaction time difference between blocks which featured a predictable sequence and those that did not. Surprise-related slowing was indexed as the reaction time difference between surprising and unsurprising trials. No differences in sequence-learning or surprise-related slowing were observed between the groups. Bayesian statistics provided anecdotal to moderate evidence to support the conclusion that sequence learning and surprise-related slowing were comparable between the two groups. We conclude that individuals with autism do not show atypicalities in response to surprising events in the context of motor sequence-learning. These data demand careful consideration of the way in which Bayesian accounts of autism can (and cannot) be extended to the domain of motor learning.

Temporal preparation in adults with autistic spectrum disorder: The variable foreperiod effect

Research suggested the possibility that temporal cognition may be different in autistic spectrum disorder (ASD). Although there are some empirical studies examining timing ability in these individuals, to our knowledge, no one directly assessed the ability to predict when an event will occur. Here, we report a study on implicit temporal preparation in individuals with ASD as indexed by the variable foreperiod (FP) effect. We compared a group of adult ASD participants to a group of typically-developed (TD) controls, for their respective abilities to utilize implicit temporal information in a simple detection task with three different preparatory intervals (FP, short, middle and long). Participants were given a warning tone to signal an imminent stimulus, and asked to press a key as quickly as they could upon detection of the stimulus. Both groups were able to use implicit temporal information, as revealed by both the variable-FP effect (i.e., faster response for targets appearing after a long FP) and asymmetric sequential effects (i.e., slower response in short-FP trials following a previous long-FP trial). The TD group exhibited a faster response in a long-FP trial that was preceded by short-FP one, whereas the ASD group did not, as reflected in their higher percentage of response omissions for a target that appeared later than in the previous trial. The reduced ability of ASD participants to modulate their responses under these conditions might reflect a difficulty in time-based monitoring of stimulus occurrence. LAY SUMMARY: Time-processing may be different in autistic spectrum disorder (ASD). This study addressed the ability to anticipate a relevant stimulus's onset according to predictable interstimulus intervals comparing adults with ASD and typically developed controls. We found that ASD participants did not benefit from temporal preparation when stimulus appeared later than previously attended. This suggests a reduced ability in detecting implicit temporal regularities between events.

Hammering that Nail: Varied Praxis Motor Skills in Younger Autistic Children

Previous studies measuring praxis abilities in young autistic children have only used praxis measures that were not optimised for autistic individuals. Hence, we used the FAB-R to measure praxis skills in autistic (n = 38) and typically developing (TD) children (n = 38) aged between four and 10 years. Praxis abilities were generally not different between autistic and TD children. However, total dyspraxia and errors during verbal command and tool use were impaired in autistic children from a specialist autistic school (SAS). In contrast, autistic participants from the GC typically did not differ in praxis performance compared to controls. Hence, praxis abilities significantly vary between autistic younger children. Exploring mediating influences of such variability is imperative.

A metabolomics approach to investigate urine levels of neurotransmitters and related metabolites in autistic children

Since recently metabolic abnormalities in autistic children have been associated with ASD disturbs, the aim of this study is to determine the neurotransmitter levels in urine samples of autistic children and to analyse the altered metabolic pathway involved in their production. Thus, ASD-specific urinary metabolomic patterns were explored in 40 ASD children and 40 matched controls using untargeted metabolomics through UHPLC-mass spectrometry (Q-exactive analyser), and by using XCMS Metlin software for data interpretation. Through this new advanced technique, a more considerable number of urinary altered metabolites were recorded in autistic children, than in the previous investigations, which allowed us to collect metabolites involved in neurotransmitter production. In these subjects, a high amount of dopamine was revealed and an increased amount of homovanillic acid, to the detriment of noradrenaline and adrenaline production, as well as MHPG and vanillylmandelic acid, which were found lower. This indicates that the accumulation of dopamine is not due to its greater production, but its lesser biotransformation into noradrenaline, due to the blockage of the dopamine β-hydroxylase enzyme by 4-cresol and vitamin C, both found in high quantities in autistic subjects. Finally, a decreased amount of the active form of vitamin B6, pyridoxal phosphate (P5P), implicated in biotransformation of glutamate into γ-aminobutyric acid (GABA), was also detected, justifying the lower levels of latter. All of these alterations are correlated with a peculiar intestinal microbiome in autistic subjects, supporting the idea of a microbiota-gut-brain axis, then altered levels of neurotransmitters and altered neuronal transmission exist.

Motor atypicalities in infancy are associated with general developmental level at 2 years, but not autistic symptoms

LAY ABSTRACT

Atypicalities in motor functioning are often observed in later born infant siblings of children with autism spectrum disorder. The goal of our study was to investigate motor functioning in infants with and without familial history of autism spectrum disorder. Specifically, we investigated how infants catch a ball that is rolling toward them following a non-straight path, a task that requires both efficient planning and execution. Their performance was measured using detailed three-dimensional motion capture technology. We found that several early motor functioning measures were different in infants with an older autistic sibling compared to controls. However, these early motor measures were not related to autistic symptoms at the age of 2 years. Instead, we found that some of the early motor measures were related to their subsequent non-social, general development. The findings of our study help us understand motor functioning early in life and how motor functioning is related to other aspects of development.

Facilitating sensorimotor integration via blocked practice underpins imitation learning of atypical biological kinematics in autism spectrum disorder

The reduced efficacy of voluntary imitation in autism is suggested to be underpinned by differences in sensorimotor processing. We examined whether the imitation of novel atypical biological kinematics by autistic adults is enhanced by imitating a model in a predictable blocked practice trial order. This practice structure is expected to facilitate trial-to-trial sensorimotor processing, integration and encoding of biological kinematics. The results showed that neurotypical participants were generally more effective at imitating the biological kinematics across all experimental phases. Importantly, and compared to a pre-test where imitation was performed in a randomised (unpredictable) trial order, the autistic participants learned to imitate the atypical kinematics more effectively following an acquisition phase of repeatedly imitating the same model during blocked practice. Data from the post-test showed that autistic participants remained effective at imitating the atypical biological kinematics when the models were subsequently presented in a randomised trial order. These findings show that the reduced efficacy of voluntary imitation in autism can be enhanced during learning by facilitating trial-to-trial processing and integration of sensorimotor information using blocked practice.

Requirements for Robotic Interpretation of Social Signals “in the Wild”: Insights from Diagnostic Criteria of Autism Spectrum Disorder

The last few decades have seen widespread advances in technological means to characterise observable aspects of human behaviour such as gaze or posture. Among others, these developments have also led to significant advances in social robotics. At the same time, however, social robots are still largely evaluated in idealised or laboratory conditions, and it remains unclear whether the technological progress is sufficient to let such robots move “into the wild”. In this paper, we characterise the problems that a social robot in the real world may face, and review the technological state of the art in terms of addressing these. We do this by considering what it would entail to automate the diagnosis of Autism Spectrum Disorder (ASD). Just as for social robotics, ASD diagnosis fundamentally requires the ability to characterise human behaviour from observable aspects. However, therapists provide clear criteria regarding what to look for. As such, ASD diagnosis is a situation that is both relevant to real-world social robotics and comes with clear metrics. Overall, we demonstrate that even with relatively clear therapist-provided criteria and current technological progress, the need to interpret covert behaviour cannot yet be fully addressed. Our discussions have clear implications for ASD diagnosis, but also for social robotics more generally. For ASD diagnosis, we provide a classification of criteria based on whether or not they depend on covert information and highlight present-day possibilities for supporting therapists in diagnosis through technological means. For social robotics, we highlight the fundamental role of covert behaviour, show that the current state-of-the-art is unable to characterise this, and emphasise that future research should tackle this explicitly in realistic settings.

Whole-Body Movement during Videogame Play Distinguishes Youth with Autism from Youth with Typical Development

Individuals with autism spectrum disorder struggle with motor difficulties throughout the life span, and these motor difficulties may affect independent living skills and quality of life. Yet, we know little about how whole-body movement may distinguish individuals with autism spectrum disorder from individuals with typical development. In this study, kinematic and postural sway data were collected during multiple sessions of videogame play in 39 youth with autism spectrum disorder and 23 age-matched youth with typical development (ages 7–17 years). The youth on the autism spectrum exhibited more variability and more entropy in their movements. Machine learning analysis of the youths’ motor patterns distinguished between the autism spectrum and typically developing groups with high aggregate accuracy (up to 89%), with no single region of the body seeming to drive group differences. Moreover, the machine learning results corresponded to individual differences in performance on standardized motor tasks and measures of autism symptom severity. The machine learning algorithm was also sensitive to age, suggesting that motor challenges in autism may be best characterized as a developmental motor delay rather than an autism-distinct motor profile. Overall, these results reveal that whole-body movement is a distinguishing feature in autism spectrum disorder and that movement atypicalities in autism are present across the body.

The Impact of Different Movement Types on Motor Planning and Execution in Individuals With Autism Spectrum Disorder

Although there are consistent reports that motor skills are affected in individuals with autism, the details are still debated; specifically, why individuals spend more time preparing movements and whether or not movement execution takes longer. The present study investigated if the conflicting reports were related to: (a) differences in movement type and (b) if longer reaction times were related to the time for motor planning or for force-generation processes. Participants performed three different movement types. People with autism had longer premotor reaction times and movement times for the three-dimensional movements only. We suggest individuals with autism have difficulty planning and executing unconstrained reaching movements specifically. The present results are consistent with evidence that autistic individuals have more difficulty effectively using visual feedback but can use tactile feedback to execute reaching movements efficiently and accurately.

Older Adolescents and Young Adults With Autism Spectrum Disorder Have Difficulty Chaining Motor Acts When Performing Prehension Movements Compared to Typically Developing Peers

It is known that motor actions performed by individuals with autism spectrum disorders (ASD) are clumsy and a previous study revealed that children with ASD of around 8 years old showed less smooth movement and dysfunction of appropriate usage of online vision for grip aperture control. The present study investigates whether and how the kinematic properties of reach-to-grasp movements in older adolescents and adults with ASD [mean (±SD) age: 18.3 ± 2.1] differ from those in typically developing (TD) peers [mean (±SD) age: 19.1 ± 2.2]. Revealing the kinematic properties of reach-to-grasp movements in older adolescents and adults with ASD is indispensable in determining the developmental trajectory of this motor behavior in individuals with ASD. While wearing liquid crystal shutter goggles, participants reached for and grasped a cylinder with a diameter of either 4 or 6 cm. Two visual conditions were tested: a full vision (FV) condition (the goggles remained transparent during the movement) and a no vision (NV) condition (the goggles were closed immediately after the movement was initiated). These two visual conditions were either alternated with each trial in a single experimental session (alternated condition) or blocked within the session (blocked condition). We found that the reaching movement smoothness calculated as a normalized jerk score (i.e., index of skilled, coordinated human movements) of ASD participants did not differ significantly from that of TD peers although ASD participants showed smoother reaching in the alternated condition than in the blocked condition. The influence of online vision and its visual condition schedule on grip aperture during the in-flight phase was remarkably similar between the ASD and TD groups. Furthermore, we found that ASD group experienced a significant longer transition period from grasping end (i.e., stable holding when touching the surface of the object) to uplift initiation than the TD group. The results suggest that (1) deficits in movement smoothness and the use of online vision for motor control are rectified by the time individuals with ASD reach late adolescence and (2) older adolescents and adults with ASD still have difficulties chaining motor acts.

Interpersonal motor coordination during joint actions in children with and without autism spectrum disorder: The role of motor information

BACKGROUND

Kinematics plays a key role in action prediction, imitation and joint action coordination. Despite people with autism spectrum disorder (ASD) show a failure to use kinematic cues during observation and imitation, there is a paucity of studies exploring the role of this dysfunction during joint actions in children with ASD.

AIM

To evaluate the interpersonal motor coordination of children with ASD and typically developing (TD) children during a joint action task.

METHOD

Twenty-two participants performed two cooperative tasks. In the first one (Clear End-Point), children were provided with a priori information on movement end-point. In the second one (Unclear End-Point), the end-point was unknown and children had to use kinematic cues to accomplish the shared goal.

RESULTS

We found no between-group differences in the first task, even if children with ASD displayed greater reaction time variability. In the second task, they showed less accurate and slower movements than TD children. Moreover, their movement features did not differ between the two tasks, whereas TD children showed reduced reaction time variability and number of errors in the second task.

CONCLUSION

Children with ASD were impaired in joint action coordination when they had to rely only on kinematic information. They were not able to pay more attention to the kinematic cues in absence of a visual goal.

The impact of auditory rhythmic cueing on gross motor skills in children with autism

[Purpose] This study aimed to investigate the effect of auditory rhythmic cueing on gross motor skills in children with autism. [Participants and Methods] A total of 30 autistic children aged 8–10 years with mild to moderate autistic features participated in this study. They were randomly allocated to either the control group (n=15), which underwent a specially designed physical therapy program, or the study group (n=15), which underwent the same program in addition to gait training with rhythmic auditory stimulation. To provide rhythmic auditory stimulation, combination of a metronome beat set to the child’s cadence and rhythmic cueing from the MIDI Cuebase musical program was used. Both groups received 3 sessions per week for 3 months. The Bruininks-Oseretsky Test of Motor Proficiency 2nd Edition was used to assess gross motor skills at baseline and after 3 months of intervention. [Results] The study found statistically significant improvements in bilateral coordination, balance, running speed and agility, and strength in both groups after treatment. Moreover, there were statistically significant differences between the 2 groups, with the study group showing better improvement in all outcome measures. [Conclusion] Gait training with auditory rhythmic cueing elicited a positive effect on the gross motor skills of children with autism.

Neuromagnetic Beta-Band Oscillations during Motor Imitation in Youth with Autism

Children with ASD often exhibit early difficulties with action imitation, possibly due to low-level sensory or motor impairments. Impaired cortical rhythms have been demonstrated in adults with ASD during motor imitation. While those oscillations reflect an age-dependent process, they have not been fully investigated in youth with ASD. We collected magnetoencephalography data to examine patterns of oscillatory activity in the mu (8-13 Hz) and beta frequency (15-30 Hz) range in 14 adolescents with and 14 adolescents without ASD during a fine motor imitation task. Typically developing adolescents exhibited adult-like patterns of motor signals, e.g., event-related beta and mu desynchronization (ERD) before and during the movement and a postmovement beta rebound (PMBR) after the movement. In contrast, those with ASD exhibited stronger beta and mu-ERD and reduced PMBR. Behavioral performance was similar between groups despite differences in motor cortical oscillations. Finally, we observed age-related increases in PBMR and beta-ERD in the typically developing children, but this correlation was not present in the autism group. These results suggest reduced inhibitory drive in cortical rhythms in youth with autism during intact motor imitation. Furthermore, impairments in motor brain signals in autism may not be due to delayed brain development. In the context of the excitation-inhibition imbalance perspectives of autism, we offer new insights into altered organization of neurophysiological networks.

Sensory and motor differences in Autism Spectrum Conditions and developmental coordination disorder in children: A cross-syndrome study

Recent research has shown that Developmental coordination disorder (DCD) can present with some similar symptomology as Autism Spectrum Conditions (ASC). This paper therefore explored the similarities and differences in coordination and sensory responsivity between DCD and ASC. 77 children took part: 42 (35 male, 7 female) with ASC (ages 7-21: mean age 12.23 years), 26 (19 male, 7 female) with DCD (ages 7-21; mean age 11.07 years) and 9 (2 male, 7 female) with ASC and DCD (ages 8-15; mean age 12.27). All groups completed a battery of validated parent report measures online that included motor coordination (DCDQ), sensory responsivity (SPC-R) and social communication measures (AQ). Results showed no significant differences in coordination, and some significant differences in sensory responsivity between ASC and DCD (increased visual and auditory responsivity and decreased proprioception). Exploratory analysis showed that these differences showed good validity in identifying the diagnosis of ASC and DCD. These results elucidate the underlying causes of motor coordination difficulties in both conditions. Specifically, ASC coordination difficulties appear linked to visual processing impairments, whilst DCD coordination difficulties appear to be linked to spatial processing. This may aid better diagnosis and intervention for these conditions.

Objective measurement of head movement differences in children with and without autism spectrum disorder

Background

Deficits in motor movement in children with autism spectrum disorder (ASD) have typically been characterized qualitatively by human observers. Although clinicians have noted the importance of atypical head positioning (e.g. social peering and repetitive head banging) when diagnosing children with ASD, a quantitative understanding of head movement in ASD is lacking. Here, we conduct a quantitative comparison of head movement dynamics in children with and without ASD using automated, person-independent computer-vision based head tracking (Zface). Because children with ASD often exhibit preferential attention to nonsocial versus social stimuli, we investigated whether children with and without ASD differed in their head movement dynamics depending on stimulus sociality.

Methods

The current study examined differences in head movement dynamics in children with (n = 21) and without ASD (n = 21). Children were video-recorded while watching a 16-min video of social and nonsocial stimuli. Three dimensions of rigid head movement—pitch (head nods), yaw (head turns), and roll (lateral head inclinations)—were tracked using Zface. The root mean square of pitch, yaw, and roll was calculated to index the magnitude of head angular displacement (quantity of head movement) and angular velocity (speed).

Results

Compared with children without ASD, children with ASD exhibited greater yaw displacement, indicating greater head turning, and greater velocity of yaw and roll, indicating faster head turning and inclination. Follow-up analyses indicated that differences in head movement dynamics were specific to the social rather than the nonsocial stimulus condition.

Conclusions

Head movement dynamics (displacement and velocity) were greater in children with ASD than in children without ASD, providing a quantitative foundation for previous clinical reports. Head movement differences were evident in lateral (yaw and roll) but not vertical (pitch) movement and were specific to a social rather than nonsocial condition. When presented with social stimuli, children with ASD had higher levels of head movement and moved their heads more quickly than children without ASD. Children with ASD may use head movement to modulate their perception of social scenes.

Electronic supplementary material

The online version of this article (10.1186/s13229-018-0198-4) contains supplementary material, which is available to authorized users.

IQ discrepancy differentiates levels of fine motor skills and their relationship in children with autism spectrum disorders

PURPOSE

We investigated 1) the impact of differences in intelligence quotient discrepancy (IQD) on motor skills of preschool-aged children with autism spectrum disorders (ASD); 2) the relationships between IQD and motor skills in preschool-aged children with ASD.

METHODS

A total of 127 ASD preschool-aged children were divided into three groups according to the size of the IQD: IQD within 1 standard deviation (1SD; EVENIQ; n=81), discrepantly higher verbal intelligence quotient (VIQ; n=22; VIQ>performance intelligence quotient [PIQ] above 1SD [≥15 points]), and discrepantly higher PIQ (n=24; PIQ>VIQ above 1SD [≥15 points]). Children's IQD and motor skills were determined with the Wechsler Preschool and Primary Scale of Intelligence™ - Fourth Edition and the motor subtests of the Comprehensive Developmental Inventory for Infants and Toddlers (CDIIT), respectively.

RESULTS

One-way analysis of variance revealed significant group differences for the fine motor domain of the CDIIT and the visual-motor coordination subtest (F=3.37-4.38, p<0.05). Children with discrepantly higher PIQ were associated with better fine motor skills than were children with even IQD and those with discrepantly higher VIQ, and vice versa. IQD (PIQ - VIQ) had significant positive correlations with the fine motor domain and fine motor subtests of the CDIIT (r=0.18-0.29, p<0.05).

CONCLUSION

The IQD can identify different levels of fine motor skills in preschool-aged children with ASD. This study suggests important implications for clinicians, therapists, and researchers: discrepantly higher PIQ could be related to better visual-motor coordination, and discrepantly higher VIQ could be related to poor visual-motor coordination. Furthermore, the results support that when therapists are working with preschool-aged children with ASD who are developing fine motor skills or undertaking fine motor tasks related to visual-motor coordination, they may need to pay attention to the children's IQD.

Do Handwriting Difficulties Correlate with Core Symptomology, Motor Proficiency and Attentional Behaviours?

Handwriting is commonly identified as an area of weakness in children with autism spectrum disorder (ASD), but precise deficits have not been fully characterised. Boys with ASD (n = 23) and matched controls (n = 20) aged 8-12 years completed a simple, digitised task to objectively assess handwriting performance using advanced descriptive measures. Moderate to large associations were identified between handwriting performance and attention, ASD symptoms and motor proficiency. The ASD group demonstrated significantly less smooth movements and significantly greater sizing variability and peak velocity relative to controls. These findings provide a clearer indication of the specific nature of handwriting impairments in children with ASD, and suggest a relationship with core clinical symptom severity, attention and motor behaviours.

Motor coordination impairment in children with autism spectrum disorder: a pilot study using Movement Assessment Battery for Children-2 Checklist

BACKGROUND

Some research suggests that children with autism spectrum disorder (ASD) experience diverse motor difficulties that appear closely related to the severity of symptomatology, including repetitive behaviors. Therefore, motor assessment in ASD has crucial relevance in order to plan a specific intervention. The aim of this study is to assess and describe the motor functioning in school-aged children with ASD and to evaluate the relationship between their motor profile and clinical features.

METHODS

The Movement Assessment Battery for Children - second edition (M-ABC2) Checklist was administered to twenty children with ASD, aged between 5 and 13.5 years. The motor profile of the sample was analyzed and then the relationship between the motor functioning and the clinical characteristics of subjects (age, treatment duration, intellectual functioning and repetitive behaviors) was investigated.

RESULTS

Seventy percent of our sample has motor difficulties, especially in aiming and catching skills, balance and manual dexterity. Poorer performance was related to a higher frequency and intensity of repetitive and stereotyped behaviors.

CONCLUSIONS

Motor difficulties in children with ASD affect specific skills that imply the ability to integrate the perception with the action for anticipating and controlling the movement in a well-coordinated way. This result, along with the finding of an increased severity of repetitive and stereotyped behaviors in these children, emphasizes the close link between motor and "core" symptoms in ASD.

Interlimb coordination and academic performance in elementary school children

BACKGROUND

The specific mechanisms linking motor ability and cognitive performance, especially academic achievement, are still unclear. Whereas the literature provides an abundance of information on fine and visual-motor skill and cognitive attributes, much less has been reported on gross motor ability. This study examined interlimb coordination and its relationship to academic performance in children aged 8-11 years.

METHODS

Motor and academic skills were examined in 100 Brazilian children using the Bruininks-Oseretsky Test of Motor Proficiency and the Academic Performance Test. Participants were grouped into low (<25%) and high (>75%) academic achievers.

RESULTS

There was a significant difference between groups for Total Motor Composite (P < 0.001) favoring the high group. On regression analysis there was a significant association between academic performance and Body Coordination. Of the subtests of Body Coordination (Bilateral Coordination and Balance), Bilateral Coordination accounted for the highest impact on academic performance. Of interest here, that subtest consists primarily of gross motor tasks involving interlimb coordination.

CONCLUSION

Overall, there was a positive relationship between motor behavior, in particular activities involving interlimb coordination, and academic performance. Application of these findings in the area of early assessment may be useful in the identification of later academic problems.

Attentional Networks in Adolescents with High-functioning Autism: An fMRI Investigation

Background:

Attentional deficits in Autism spectrum disorder (ASD) are often noted, but their specific nature remains unclear.

Objective:

The present study used the child Attentional Network Task (Child ANT) in combination with functional magnetic resonance imaging (fMRI) to determine if the consistently cited deficits of orienting attention are truly due to dysfunctions of orienting-based networks. We hypothesized that these observations are, in fact, a reflection of executive dysfunctions. As such, we expected that although ASD adolescents would perform worse on the orienting portion of the Child ANT, the strongest differences in activation between them and the neurotypical (NT) control group would be in areas classically associated with executive functioning (e.g., the frontal gyri and anterior cingulate cortex).

Method:

The brain activity of six high-functioning adolescents with ASD and six NT adolescents was recorded while these individuals performed the three subcomponents of the Child ANT.

Results:

ASDs were shown to be more accurate than NTs for the alerting, less accurate for the orienting, and similar in accuracy for the executive portions of the Child ANT. fMRI data showed increased bilateral frontal gyri recruitment, areas conventionally associated with executive control, during the orienting task for the ASD group.

Conclusion:

We submit that the increased activations represent neurocorrelates of signal fixation attributable to the subset of executive control responsible for sustained maintenance signals, not the main components of orienting. Therefore, excessive fixation in ASD adolescents is likely due to dysfunctions of executive control and not the orienting subcomponent of the attention network.

The Role of Sensorimotor Difficulties in Autism Spectrum Conditions

In addition to difficulties in social communication, current diagnostic criteria for autism spectrum conditions (ASC) also incorporate sensorimotor difficulties, repetitive motor movements, and atypical reactivity to sensory input (1). This paper explores whether sensorimotor difficulties are associated with the development and maintenance of symptoms in ASC. First, studies have shown difficulties coordinating sensory input into planning and executing movement effectively in ASC. Second, studies have shown associations between sensory reactivity and motor coordination with core ASC symptoms, suggesting these areas each strongly influence the development of social and communication skills. Third, studies have begun to demonstrate that sensorimotor difficulties in ASC could account for reduced social attention early in development, with a cascading effect on later social, communicative and emotional development. These results suggest that sensorimotor difficulties not only contribute to non-social difficulties such as narrow circumscribed interests, but also to the development of social behaviors such as effectively coordinating eye contact with speech and gesture, interpreting others' behavior, and responding appropriately. Further research is needed to explore the link between sensory and motor difficulties in ASC and their contribution to the development and maintenance of ASC.

Nature of motor imitation problems in school-aged boys with autism

This case-control study explores the underlying mechanisms of imitation problems in boys with autism by manipulating imitation task variables and by correlating imitation performance with competence on general motor tests (Movement Assessment Battery for Children and Peabody Developmental Motor Scales). Fifty-five boys participated in this study: eight low-functioning with autism (LFA), 13 with mental retardation (MR), 17 high-functioning with autism (HFA) and 17 typically developing (TD). LFA performed significantly worse than MR on the motor test and on all imitation tasks. HFA performed significantly worse than TD on the motor test, but not on imitation tasks, with the exception of non-meaningful gestures. This study supports the notion that mainly perceptual-motor impairment, and not a cognitive weakness of symbolic representation, causes imitation problems in autism. In addition, in boys with autism, general motor as well as imitation abilities were impaired. We suggest that imitation ability has to be assessed in conjunction with motor competence.

Longitudinal development of manual motor ability in autism spectrum disorder from childhood to mid-adulthood relates to adaptive daily living skills

Many individuals with autism spectrum disorder (ASD) exhibit motor difficulties, but it is unknown whether manual motor skills improve, plateau, or decline in ASD in the transition from childhood into adulthood. Atypical development of manual motor skills could impact the ability to learn and perform daily activities across the life span. This study examined longitudinal grip strength and finger tapping development in individuals with ASD (n = 90) compared to individuals with typical development (n = 56), ages 5 to 40 years old. We further examined manual motor performance as a possible correlate of current and future daily living skills. The group with ASD demonstrated atypical motor development, characterized by similar performance during childhood but increasingly poorer performance from adolescence into adulthood. Grip strength was correlated with current adaptive daily living skills, and Time 1 grip strength predicted daily living skills eight years into the future. These results suggest that individuals with ASD may experience increasingly more pronounced motor difficulties from adolescence into adulthood and that manual motor performance in ASD is related to adaptive daily living skills.

Comorbidity of ADHD and High-functioning Autism: A Pilot Study on the Utility of the Overflow Movements Measure

OBJECTIVES

Children with attention-deficit/hyperactivity disorder (ADHD) and high-functioning autism (HFA) commonly show neurological soft signs (NSS) and impairment in executive functioning (EF). Many children with HFA may experience ADHD-like symptoms, and the 2 disorders may be comorbid. Evaluating NSS and EF in drug-naive subjects with ADHD, HFA, and ADHD+HFA compared with healthy children may be critical in understanding and differentiating the biological substrates and cognitive phenotypes associated with these disorders. The goal of this study was to evaluate possible differences among these groups in motor and EF and the effects of comorbidity.

METHODS

Thirty-eight drug-naive patients (13 with ADHD, 13 with HFA, 12 with ADHD+HFA) and 13 healthy controls (HC) were evaluated on measures of planning, verbal working memory, and response inhibition. Evaluation of NSS involved 3 primary variables: overflow movements (OM), dysrhythmia, and speed of timed activities.

RESULTS

The group with ADHD and the group with HFA both showed impairment on measures of planning, response inhibition, and verbal working memory compared with the HC group. Moreover, the group with ADHD showed a greater number of NSS compared with the HC group, whereas the group with HFA showed greater dysrhythmia and slowness compared with the HC group. The group with ADHD+HFA showed deficits of planning and response inhibition and a greater number of NSS compared with the HC group. The group with ADHD+HFA showed greater impairment of planning compared with the other clinical groups and greater dysrhythmia compared with the group with ADHD.

CONCLUSION

According to our data, the OM measure revealed a gradient in which ADHD was at one extreme (more OM) and HFA at the other extreme (less OM), whereas ADHD+HFA showed a number of OM that fell in the middle between the numbers for the ADHD and HFA groups.

Determinants and challenges in physical activity participation in families with children with high functioning autism spectrum disorders from a family systems perspective

The underlying factors affecting physical activity (PA) participation of children with high-functioning autism spectrum disorders (HFASDs) and their family members were investigated using a mixed method research design. Six families with children with HFASD aged 4 through 13 participated in the study. Findings revealed that levels of moderate to vigorous physical activity (MVPA) in children with HFASD varied between 85 min and 405 min for seven days. Parents of children with HFASD in this study were inactive (levels of MVPA varied between 6 min and 53 min) during this period. Qualitative data from parents highlighted many essential issues. Those issues are categorized under three main themes: (a) understanding PA in children with HFASD, (b) living with a child with HFASD, and (c) awareness of autism spectrum disorders (ASD) at school and community settings. Social skills, issues related to bullying, fear of injury to the child, as well as support from family members and lack of understanding of the disability emerged as subthemes extracted from these data.

Implicit and explicit motor learning: Application to children with Autism Spectrum Disorder (ASD)

AIMS AND OBJECTIVES

This study aims to determine whether children with Autism Spectrum Disorder (ASD) are capable of learning a motor skill both implicitly and explicitly.

METHODS

In the present study, 30 boys with ASD, aged 7-11 with IQ average of 81.2, were compared with 32 typical IQ- and age-matched boys on their performance on a serial reaction time task (SRTT). Children were grouped by ASD and typical children and by implicit and explicit learning groups for the SRTT.

RESULTS

Implicit motor learning occurred in both children with ASD (p=.02) and typical children (p=.01). There were no significant differences between groups (p=.39). However, explicit motor learning was only observed in typical children (p=.01) not children with ASD (p=.40). There was a significant difference between groups for explicit learning (p=.01).

DISCUSSION

The results of our study showed that implicit motor learning is not affected in children with ASD. Implications for implicit and explicit learning are applied to the CO-OP approach of motor learning with children with ASD.

Biochemistry of the cingulate cortex in autism: An MR spectroscopy study

Neuroimaging studies have uncovered structural and functional alterations in the cingulate cortex in individuals with autism spectrum disorders (ASD). Such abnormalities may underlie neurochemical imbalance. In order to characterize the neurochemical profile, the current study examined the concentration of brain metabolites in dorsal ACC (dACC) and posterior cingulate cortex (PCC) in high-functioning adults with ASD. Twenty high-functioning adults with ASD and 20 age-and-IQ-matched typically developing (TD) peers participated in this Proton magnetic resonance spectroscopy (1H-MRS) study. LCModel was used in analyzing the spectra to measure the levels of N-Acetyl aspartate (NAA), choline (Cho), creatine (Cr), and glutamate/glutamine (Glx) in dACC and PCC. Groups were compared using means for the ratio of each metabolite to their respective Cr levels as well as on absolute internal-water-referenced measures of each metabolite. There was a significant increase in Cho in PCC for ASD adults, with a marginal increase in dACC. A reduction in NAA/Cr in dACC was found in ASD participants, compared to their TD peers. No significant differences in Glx/Cr or Cho/Cr were found in dACC. There were no statistically significant group differences in the absolute concentration of NAA, Cr, Glx, or NAA/Cr, Cho/Cr, and Glx/Cr in the PCC. Differences in the metabolic properties of dACC compared to PCC were also found. Results of this study provide evidence for possible cellular and metabolic differences in the dACC and PCC in adults with ASD. This may suggest neuronal dysfunction in these regions and may contribute to the neuropathology of ASD. Autism Res 2016, 9: 643-657. © 2015 International Society for Autism Research, Wiley Periodicals, Inc.

The use of action phrases in individuals with Autism Spectrum Disorder

Previous research has shown that individuals with Autism Spectrum Disorder (ASD) may be able to perceive the intentions of another individual through tool use (e.g., Aldridge et al., 2000; Gonzalez et al., 2013). However, it is not well understood how individuals with ASD respond to an indirect connection between an extrapolated action and the required object. To address this question, we employed action phrases that indirectly provided the contextual information about which object to use. Individuals with ASD, and sex and age matched typically developing peers, were asked to pick which object would be needed to complete the task described in a sentence displayed on a computer screen. Although individuals with ASD exhibited slower response times overall, their accuracy scores were comparable to typically developing individuals. The longer response times support the notion that individuals with ASD may have a harder time disengaging their initial perceived use for the object before considering other inherent action possibilities afforded by the object.

The sense of agency in autism spectrum disorders: a dissociation between prospective and retrospective mechanisms?

While a large number of studies have reported impairments in social and interpersonal abilities in individuals with autism spectrum disorder (ASD), relatively few studies have focused on self-related knowledge in this population. One of the processes implicated in the physical dimension of the Self is the sense of agency (SoA), i.e., the experience of initiating and controlling one’s own actions and producing desired changes in the world via these actions. So far, the few studies investigating SoA in ASD have reported contrasting results, with some showing spared, others impaired SoA. Here, we review the existing literature and suggest that the distinction between prospective and retrospective mechanisms of the SoA might help reconcile the existing findings. In the light of a multi-componential model of SoA, we propose the view that a specific impairment at the level of prospective mechanisms acting on internal agency signals (i.e., the intention, action selection, or command produced to achieve the goal) may be responsible for the reduced SoA in ASD, along with spared retrospective mechanisms. Future research should shed light on the impact of abnormal SoA on social and self-related dysfunctions in ASD.

Altered modulation of gamma oscillation frequency by speed of visual motion in children with autism spectrum disorders

BACKGROUND

Recent studies link autism spectrum disorders (ASD) with an altered balance between excitation and inhibition (E/I balance) in cortical networks. The brain oscillations in high gamma-band (50-120 Hz) are sensitive to the E/I balance and may appear useful biomarkers of certain ASD subtypes. The frequency of gamma oscillations is mediated by level of excitation of the fast-spiking inhibitory basket cells recruited by increasing strength of excitatory input. Therefore, the experimental manipulations affecting gamma frequency may throw light on inhibitory networks dysfunction in ASD.

METHODS

Here, we used magnetoencephalography (MEG) to investigate modulation of visual gamma oscillation frequency by speed of drifting annular gratings (1.2, 3.6, 6.0 °/s) in 21 boys with ASD and 26 typically developing boys aged 7-15 years. Multitaper method was used for analysis of spectra of gamma power change upon stimulus presentation and permutation test was applied for statistical comparisons. We also assessed in our participants visual orientation discrimination thresholds, which are thought to depend on excitability of inhibitory networks in the visual cortex.

RESULTS

Although frequency of the oscillatory gamma response increased with increasing velocity of visual motion in both groups of participants, the velocity effect was reduced in a substantial proportion of children with ASD. The range of velocity-related gamma frequency modulation correlated inversely with the ability to discriminate oblique line orientation in the ASD group, while no such correlation has been observed in the group of typically developing participants.

CONCLUSIONS

Our findings suggest that abnormal velocity-related gamma frequency modulation in ASD may constitute a potential biomarker for reduced excitability of fast-spiking inhibitory neurons in a subset of children with ASD.

Comparing Motor Skills in Autism Spectrum Individuals With and Without Speech Delay

Movement atypicalities in speed, coordination, posture, and gait have been observed across the autism spectrum (AS) and atypicalities in coordination are more commonly observed in AS individuals without delayed speech (DSM‐IV Asperger) than in those with atypical or delayed speech onset. However, few studies have provided quantitative data to support these mostly clinical observations. Here, we compared perceptual and motor performance between 30 typically developing and AS individuals (21 with speech delay and 18 without speech delay) to examine the associations between limb movement control and atypical speech development. Groups were matched for age, intelligence, and sex. The experimental design included: an inspection time task, which measures visual processing speed; the Purdue Pegboard, which measures finger dexterity, bimanual performance, and hand‐eye coordination; the Annett Peg Moving Task, which measures unimanual goal‐directed arm movement; and a simple reaction time task. We used analysis of covariance to investigate group differences in task performance and linear regression models to explore potential associations between intelligence, language skills, simple reaction time, and visually guided movement performance. AS participants without speech delay performed slower than typical participants in the Purdue Pegboard subtests. AS participants without speech delay showed poorer bimanual coordination than those with speech delay. Visual processing speed was slightly faster in both AS groups than in the typical group. Altogether, these results suggest that AS individuals with and without speech delay differ in visually guided and visually triggered behavior and show that early language skills are associated with slower movement in simple and complex motor tasks. Autism Res2015, 8: 682–693. © 2015 The Authors Autism Research published by Wiley Periodicals, Inc. on behalf of International Society for Autism Research

Dopamine and the development of executive dysfunction in autism spectrum disorders

Persons with autism regularly exhibit executive dysfunction (ED), including problems with deliberate goal-directed behavior, planning, and flexible responding in changing environments. Indeed, this array of deficits is sufficiently prominent to have prompted a theory that executive dysfunction is at the heart of these disorders. A more detailed examination of these behaviors reveals, however, that some aspects of executive function remain developmentaly appropriate. In particular, while people with autism often have difficulty with tasks requiring cognitive flexibility, their fundamental cognitive control capabilities, such as those involved in inhibiting an inappropriate but relatively automatic response, show no significant impairment on many tasks. In this article, an existing computational model of the prefrontal cortex and its role in executive control is shown to explain this dichotomous pattern of behavior by positing abnormalities in the dopamine-based modulation of frontal systems in individuals with autism. This model offers excellent qualitative and quantitative fits to performance on standard tests of cognitive control and cognitive flexibility in this clinical population. By simulating the development of the prefrontal cortex, the computational model also offers a potential explanation for an observed lack of executive dysfunction early in life.

A technological approach to studying motor planning ability in children at high risk for ASD

In this work we propose a new method to study the development of motor planning abilities in children and, in particular, in children at high risk for ASD. Although several modified motor signs have been found in children with ASD, no specific markers enabling the early assessment of risk have been found yet. In this work, we discuss the problem posed by objective and quantitative behavioral analysis in non-structured environment. After an initial description of the main constraints imposed by the ecological approach, a technological and methodological solution to these issues is presented. Preliminary results on 12 children are reported and briefly discussed.