The Development of Sensorimotor Intelligence in Infants

Prospective Interrelation Between Sensory Sensitivity and Fine Motor Skills During the First 18 Months Predicts Later Autistic Features

Sensory features are included in the diagnostic criteria of autism and atypical sensory responsiveness may produce "cascading effects" on later development. Similarly, autistic individuals often struggle with motor coordination and early delays in the motor domain appear to be linked to later development. However, the longitudinal interrelation between early sensory profiles and motor features on later socio-communicative skills remains to be defined. This study aimed to investigate whether sensory sensitivity impacts fine motor abilities and vice versa from 12 to 18 months of age and to examine how sensory-motor interplay would be associated with later autistic traits at 24-36 months of age. The sample included 118 infant siblings of autistic children recruited at 12 months of age. Sensory sensitivity and eye-hand coordination were assessed at 12 and 18 months of age and autistic traits were evaluated at 24-36 months of age. Cross-lagged panel analysis revealed significant within-domain effects for sensory sensitivity and eye-hand coordination from 12 to 18 months. Furthermore, a significant association between these two domains on later autistic traits was found. In analyzing the longitudinal bidirectional relationship, we found that lower eye-hand coordination skills at 12 months predicted later sensory sensitivity at 18 months, and in turn, social communication skills at 24-36 months. The present study offers new empirical evidence supporting the potential clinical value of including sensory and motor measures besides social communication skills within early autism surveillance programs.

Functional structure of local connections and differentiation of cerebral cortex areas in the neonate

Neuroimaging research on functional connectivity can provide valuable information on the developmental differentiation of the infant cerebral cortex into its functional areas. We examined healthy neonates to comprehensively map brain functional connectivity using a combination of local measures that uniquely capture the rich spatial structure of cerebral cortex functional connections. Optimal functional MRI scans were obtained in 61 neonates. Local functional connectivity maps were based on Iso-Distance Average Correlation (IDAC) measures. Single distance maps and maps combining three distinct IDAC measures were used to assess different levels of cortical area functional differentiation. A set of brain areas showed higher connectivity than the rest of the brain parenchyma in each local distance map. These areas were consistent with those supporting basic aspects of the neonatal repertoire of adaptive behaviors and included the sensorimotor, auditory and visual cortices, the frontal operculum/anterior insula (relevant for sucking, swallowing and the sense of taste), paracentral lobule (processing anal and urethral sphincter activity), default mode network (relevant for self-awareness), and limbic-emotional structures such as the anterior cingulate cortex, amygdala and hippocampus. However, the results also indicate that brain areas presumed to be actively developing may not necessarily be mature. In fact, combined distance, second-level maps confirmed that the functional differentiation of the cerebral cortex into functional areas in neonates is far from complete. Our results provide a more comprehensive understanding of the developing brain systems, while also highlighting the substantial developmental journey that the neonatal brain must undergo to reach adulthood.

Parent-child sensorimotor coordination in toddlers with and without hearing loss

Infants experience the world through their actions with objects and their interactions with other people, especially their parents. Prior research has shown that school-age children with hearing loss experience poorer quality interactions with typically hearing parents, yet little is known about parent-child interactions between toddlers with hearing loss and their parents early in life. In the current study, we used mobile eye-tracking to investigate parent-child interactions in toddlers with and without hearing loss (mean ages: 19.42 months, SD = 3.41 months). Parents and toddlers engaged in a goal-directed, interactive task that involved inserting coins into a slot and required joint coordination between the parent and the child. Overall, findings revealed that deaf toddlers demonstrate typical action skills in line with their hearing peers and engage in similar interactions with their parents during social interactions. Findings also revealed that deaf toddlers explored objects more and showed more temporal stability in their motor movements (i.e. less variation in their timing across trials) than hearing peers, suggesting further adaptability of the deaf group to their atypical sensory environment rather than poorer coordination. In contrast to previous research, findings suggest an intact ability of deaf toddlers to coordinate their actions with their parents and highlight the adaptability within dyads who have atypical sensory experiences.

Bursting with Potential: How Sensorimotor Beta Bursts Develop from Infancy to Adulthood

Beta activity is thought to play a critical role in sensorimotor processes. However, little is known about how activity in this frequency band develops. Here, we investigated the developmental trajectory of sensorimotor beta activity from infancy to adulthood. We recorded EEG from 9-month-old, 12-month-old, and adult humans (male and female) while they observed and executed grasping movements. We analyzed "beta burst" activity using a novel method that combines time-frequency decomposition and principal component analysis. We then examined the changes in burst rate and waveform motifs along the selected principal components. Our results reveal systematic changes in beta activity during action execution across development. We found a decrease in beta burst rate during movement execution in all age groups, with the greatest decrease observed in adults. Additionally, we identified three principal components that defined waveform motifs that systematically changed throughout the trial. We found that bursts with waveform shapes closer to the median waveform were not rate-modulated, whereas those with waveform shapes further from the median were differentially rate-modulated. Interestingly, the decrease in the rate of certain burst motifs occurred earlier during movement and was more lateralized in adults than in infants, suggesting that the rate modulation of specific types of beta bursts becomes increasingly refined with age.SIGNIFICANCE STATEMENT We demonstrate that, like in adults, sensorimotor beta activity in infants during reaching and grasping movements occurs in bursts, not oscillations like thought traditionally. Furthermore, different beta waveform shapes were differentially modulated with age, including more lateralization in adults. Aberrant beta activity characterizes various developmental disorders and motor difficulties linked to early brain injury, so looking at burst waveform shape could provide more sensitivity for early identification and treatment of affected individuals before any behavioral symptoms emerge. More generally, comparison of beta burst activity in typical versus atypical motor development will also be instrumental in teasing apart the mechanistic functional roles of different types of beta bursts.

A review of resting-state fMRI correlations with executive functions and social cognition in bipolar disorder

BACKGROUND

Deficits in executive functions (EF) and social cognition (SC) are often observed in bipolar disorder (BD), leading to a severe impairment in engaging a functional interaction with the others and the surrounding environment. Therefore, in recent years, resting-state functional magnetic resonance imaging (rs-fMRI) studies on BD tried to identify the neural underpinnings of these cognitive domains by exploring the association between the intrinsic functional connectivity (FC) and the scores in clinical scales evaluating these domains.

METHODS

A bibliographic search on PubMed and Scopus of studies evaluating the correlations between rs-fMRI findings and EF and/or SC in BD was conducted until March 2022. Ten studies met the inclusion criteria.

RESULTS

Overall, the results of the reviewed studies showed that BD patients had FC deficits compared to healthy controls (HC) in selective resting-state networks involved in EF and SC, which include the default mode network, especially the link between medial prefrontal cortex and posterior cingulate cortex, and the sensory-motor network. Finally, it also emerged the predominant role of alterations in prefrontal connections in explaining the cognitive deficits in BD patients.

LIMITATIONS

The heterogeneity of the reviewed studies, in terms of cognitive domains explored and neuroimaging acquisitions, limited the comparability of the findings.

CONCLUSIONS

rs-fMRI studies could help deepen the brain network alterations underlying EF and SC deficits in BD, pointing the attention on the neuronal underpinning of cognition, whose knowledge may lead to the development of new neurobiological-based approaches to improve the quality of life of these patients.

Visual tracking at 4 months in preterm infants predicts 6.5-year cognition and attention

BACKGROUND

Visual tracking of moving objects requires sustained attention and prediction of the object's trajectory. We tested the hypothesis that measures of eye-head tracking of moving objects are associated to long-term neurodevelopment in very preterm infants.

METHODS

Visual tracking performance was assessed at 4 month's corrected age in 57 infants with gestational age <32 weeks. An object moved in front of the infant with sinusoidal or triangular (i.e. abrupt) turns of the direction. Gaze gain, smooth pursuit gain, and timing of gaze to object motion were analyzed. At 6.5 years the Wechsler Intelligence Scale for Children (WISC-IV), the Brown Attention Deficit Disorder (Brown ADD), and visual examination were performed.

RESULTS

Gaze gain and smooth pursuit gain at 4 months were strongly related to all WISC-IV parameters at 6.5 years. Gaze gain for the triangular and sinusoidal motion patterns related similarly to the cognitive scores. For the sinusoidal motion pattern, timing related to most Brown ADD parameters. There were no statistically significant differences in associations dependent on motion pattern. Visual function did not influence the results.

CONCLUSION

The ability to attend to and smoothly track a moving object in infancy is an early marker of cognition and attention at 6.5 years.

IMPACT

Potential long-term implications of infant visual tracking of moving objects for school-age neurodevelopment has not been previously studied in very preterm infants. Early coordination of eye and head movements in gaze gain, smooth pursuit, and timing of gaze to object motion are closely associated with cognition and attention at 6.5 years. As related functions at 6.5 years include perceptual and verbal skills, working memory, processing speed and attention, predictive elements in gaze tracking of moving objects might be a suitable target for future intervention studies.

Can urbanization accentuate hand use in the foraging activities of primates?

OBJECTIVES

How a species uses its anatomical manipulators is determined by its anatomy, physiology, and ecology. While ecology explains interspecific variation in gripping, grasping, and manipulating objects, its role in intraspecific variation in mouth- and hand-use by animals is less explored. Primates are distinguished by their prehensile capabilities and manual dexterity. In context to the adaptive pressures of urbanization on primates, we examined if mouth and hand use differed across the forest-urban gradient in food retrieval and processing under experimental and naturalistic conditions in cercopithecids, a family comprising several urbanizing primates.

MATERIALS AND METHODS

We recorded the acquisition and processing of peanuts under experimental conditions in three groups of bonnet macaques (BM, Macaca radiata) differing in their dietary dependence on packaged food items along a rural-urban gradient. To affirm the pattern obtained in the experiment, we coded food acquisition of three cercopithecid species in similar habitats from video sources.

RESULTS

Urban macaques had a disproportionately higher hand use to acquire and process peanuts while rural macaques had higher mouth use. Based on analyses of videos, urban populations of BM, Japanese macaque (M. fuscata) and vervet monkey (Chlorocebus pygerythrus) showed a bias toward hand use during food acquisition.

DISCUSSION

The adaptive pressures of urbanization, like the manual constraints of extracting packaged foods and perhaps, the need for visual-haptic exploration of novel objects seem to accentuate hand use in synanthropic groups of primates. Additional research should ascertain similar patterns in other primates and determine specific aspects of urbanization that modulate the observed trend.

Head and eyes: Looking behavior in 12- to 24-month-old infants

This study demonstrates evidence for a foundational process underlying active vision in older infants during object play. Using head-mounted eye-tracking and motion capture, looks to an object are shown to be tightly linked to and synchronous with a stilled head, regardless of the duration of gaze, for infants 12 to 24 months of age. Despite being a developmental period of rapid and marked changes in motor abilities, the dynamic coordination of head stabilization and sustained gaze to a visual target is developmentally invariant during the examined age range. The findings indicate that looking with an aligned head and eyes is a fundamental property of human vision and highlights the importance of studying looking behavior in freely moving perceivers in everyday contexts, opening new questions about the role of body movement in both typical and atypical development of visual attention.

Action prediction during real-time parent-infant interactions

Social interactions provide a crucial context for early learning and cognitive development during infancy. Action prediction-the ability to anticipate an observed action-facilitates successful, coordinated interaction and is an important social-cognitive skill in early development. However, current knowledge about infant action prediction comes largely from screen-based laboratory tasks. We know little about what infants' action prediction skills look like during real-time, free-flowing interactions with a social partner. In the current study, we used head-mounted eyetracking to quantify 9-month-old infants' visual anticipations of their parents' actions during free-flowing parent-child play. Our findings reveal that infants do anticipate their parents' actions during dynamic interactions at rates significantly higher than would be expected by chance. In addition, the frequency with which they do so is associated with child-led joint attention and hand-eye coordination. These findings are the first to reveal infants' action prediction behaviors in a more naturalistic context than prior screen-based studies, and they support the idea that action prediction is inherently linked to motor development and plays an important role in infants' social-cognitive development. A video abstract of this article can be viewed at https://www.youtube.com/watch?v=9HrmcicfiqE.

Let's Cross the Next One: Parental Scaffolding of Prospective Control Over Movement

This investigation examined parental scaffolding of children's prospective control over decisions and actions during a joint perception-action task. Parents and their 6-, 8-, 10-, and 12-year-old children (N = 128) repeatedly crossed a virtual roadway together. Guidance and control shifted from the parent to the child with increases in child age. Parents more often chose the gap that was crossed and prospectively communicated the gap choice with younger than older children. Greater use of an anticipatory gap selection strategy by parents predicted more precise timing of entry into the gap by children. This work suggests that social interaction may serve as an important experiential mechanism for the development of prospective control over decisions and actions in the perception-action domain.

Effects of Hoverboard on Balance in Young Soccer Athletes

Hoverboards are always more popular among children. Hoverboards are to them like a game or a mean of transport, but they could be used as a valid and useful instrument in children's training programs to improve their performance. In this study, we compared the athletic performance of two groups of 12 children. A total of 24 children aged between 8 and 11 years followed a similar training program for five months, but the first group used a hoverboard (Hb+ group: Age: Standard Deviation (SD) = 1.15 Mean = 9.66; Weight: SD = 5.90 Mean = 32; Height: SD = 7.64 Mean = 135.08) for some of the training time, differently from the second group (Hb- group: Age: SD = 1.15 Mean = 9.66; Weight: SD = 5.82 Mean = 31.16; Height: SD = 7.66 Mean = 136.16), which never used it. All of the children were asked to complete three tests (one leg test, stork test and balance beam walking test) before starting their own training program and after five months, to evaluate how their performances changed in terms of time. Comparing the recorded time difference between T0 and T1 of the Hb+ group with the same difference measured in Hb- group, it was found that there was a statistically significant difference (p value < 0.05) between these data for all three tests. Children who used the hoverboard in their training program achieved better result than children who did not use it. In the future, the hoverboard could help athletes to improve their performances, possibly applying it not only in football training, but even in other sports.

Tracking of unpredictable moving stimuli by pigeons

Despite being observed throughout the animal kingdom, catching a moving object is a complex task and little is known about the mechanisms that underlie this behavior in non-human animals. Three experiments examined the role of prediction in capture of a moving object by pigeons. In Experiment 1, a stimulus moved in a linear trajectory, but sometimes made an unexpected 90^o turn. The sudden turn had only a modest effect on capture and error location, and the analyses suggested that the birds had adjusted their tracking to the novel motion. In Experiment 2, the role of visual input during a turn was tested by inserting disappearances (either 1.5 cm or 4.5 cm) on both the straight and turn trials. The addition of the disappearance had little effect on capture success, but delayed capture location with the larger disappearance leading to greater delay. Error analyses indicated that the birds adapted to the post-turn, post-disappearance motion. Experiment 3 tested the role of visual input when the motion disappeared behind an occluder and emerged in either a straight line or at a 90^o angle. The occluder produced a disruption in capture success but did not delay capture. Error analyses indicated that the birds did not adjust their tracking to the new motion on turn trials following occlusion. The combined results indicate that pigeons can anticipate the future position of a stimulus, and can adapt to sudden, unpredictable changes in motion but do so better after a disappearance than after an occlusion.

The dynamics of motor learning through the formation of internal models

A medical student learning to perform a laparoscopic procedure or a recently paralyzed user of a powered wheelchair must learn to operate machinery via interfaces that translate their actions into commands for an external device. Since the user's actions are selected from a number of alternatives that would result in the same effect in the control space of the external device, learning to use such interfaces involves dealing with redundancy. Subjects need to learn an externally chosen many-to-one map that transforms their actions into device commands. Mathematically, we describe this type of learning as a deterministic dynamical process, whose state is the evolving forward and inverse internal models of the interface. The forward model predicts the outcomes of actions, while the inverse model generates actions designed to attain desired outcomes. Both the mathematical analysis of the proposed model of learning dynamics and the learning performance observed in a group of subjects demonstrate a first-order exponential convergence of the learning process toward a particular state that depends only on the initial state of the inverse and forward models and on the sequence of targets supplied to the users. Noise is not only present but necessary for the convergence of learning through the minimization of the difference between actual and predicted outcomes.