Developmental Differences in the Prospective Organisation of Goal-Directed Movement Between Children with Autism and Typically Developing Children: A Smart Tablet Serious Game Study

Movement is prospective. It structures self-generated engagement with objects and social partners and is fundamental to children’s learning and development. In autistic children, previous reports of differences in movement kinematics compared to neurotypical peers suggest its prospective organisation might be disrupted. Here, we employed a smart tablet serious game paradigm to assess differences in the feedforward and feedback mechanisms of prospective action organisation, between autistic and neurotypical preschool children. We analysed 3926 goal-directed finger movements made during smart-tablet ecological gameplay, from 28 children with Childhood Autism (ICD-10; ASD) and 43 neurotypical children (TD), aged 3-6 years old. Using linear and generalised linear mixed-effect models, we found the ASD group executed movements with longer Movement Time (MT) and Time to Peak Velocity (TTPV), lower Peak Velocity (PV), with peak velocity less likely to occur in the first movement unit, and with a greater number of Movement Units After Peak Velocity (MU-APV). Interestingly, compared to the TD group, the ASD group showed smaller increases in PV, TTPV and MT with an increase in Age (ASD x Age interaction), together with a smaller reduction in MU-APV and an increase in MU-APV at shorter target distances (ASD x Dist interaction). Our results are the first to highlight different developmental trends in anticipatory feedforward and compensatory feedback mechanisms of control, contributing to differences in movement kinematics observed between autistic and neurotypical children. These findings point to differences in integration of prospective perceptuomotor information, with implications for embodied cognition and learning from self-generated action in autism.

Relationships Between External- and Internal-Workload Variables in an Elite Female Netball Team and Between Playing Positions

Purpose: To examine relationships between external- and internal-workload variables in an elite female netball team, with consideration of positional differences. Methods: Nine elite female netball athletes had their weekly workloads monitored across their preseason and competition phases of a season. Internal workload was determined using summated heart-rate (HR) zones and session ratings of perceived exertion (sRPE), whereas external workload was determined using inertial movement units and included absolute PlayerLoad (PL), relative PL (PL per minute), accelerations (ACCEL), decelerations (DECEL), jumps, changes of direction (COD), high-intensity events, medium-intensity events, low-intensity events, PL in the forward direction, PL in the sideways direction, and PL in the vertical direction. Relationships between external- and internal-workload variables in the team and relative to playing position were examined. Results: Across the team, the strongest external workloads that correlated with summated HR zones were PL (r = .65), COD (r = .64), ACCEL (r = .61), and DECEL (r = .61). The strongest external workloads that correlated with sRPE were COD (r = .79), followed by jumps (r = .76), ACCEL (r = .75), and DECEL (r = .75). For all positions, except-goal shooter, the strongest correlation was between PL and sRPE (r = .88–.94). In the goal-shooter position, the strongest correlation was between summated HR zones and DECEL (r = .89). Conclusions: The inertial movement unit-derived external-workload variables are strongly related to common internal-workload variables. In particular, COD and sRPE appear to provide a good monitoring combination of external and internal training loads for elite netball players.

Evaluating IoT based passive water catchment monitoring system data acquisition and analysis

Water quality is the main aspect to determine the quality of aquatic systems. Poor water quality will pose a health risk for people and ecosystems. The old methods such as collecting samples of water manually and testing and analysing at lab will cause the time consuming, wastage of man power and not economical. A system is needed to provide a real-time data for environmental protection and tracking pollution sources. This paper aims to describe on how to monitor water quality continuously through IoT platform. Water Quality Catchment Monitoring System was introduced to check and monitor water quality continuously. It’s features five sensors which are temperature sensor, light intensity sensor, pH sensor, GPS tracker and Inertia Movement Unit (IMU). IMU is a new feature in the system where the direction of x and y is determined for planning and find out where a water quality problem exists by determining the flow of water. The system uses an internet wireless connection using the ESP8266 Wi-Fi Shield Module as a connection between Arduino Mega2560 and laptop. ThingSpeak application acts as an IoT platform used for real-time data monitoring.

Infants’ prospective control during object manipulation in an uncertain environment

This study investigates how infants use visual and sensorimotor information to prospectively control their actions. We gave 14-month-olds two objects of different weight and observed how high they were lifted, using a Qualisys Motion Capture System. In one condition, the two objects were visually distinct (different color condition) in another they were visually identical (same color condition). Lifting amplitudes of the first movement unit were analyzed in order to assess prospective control. Results demonstrate that infants lifted a light object higher than a heavy object, especially when vision could be used to assess weight (different color condition). When being confronted with two visually identical objects of different weight (same color condition), infants showed a different lifting pattern than what could be observed in the different color condition, expressed by a significant interaction effect between object weight and color condition on lifting amplitude. These results indicate that (a) visual information about object weight can be used to prospectively control lifting actions and that (b) infants are able to prospectively control their lifting actions even without visual information about object weight. We argue that infants, in the absence of reliable visual information about object weight, heighten their dependence on non-visual information (tactile, sensorimotor memory) in order to estimate weight and pre-adjust their lifting actions in a prospective manner.

Infants prospectively control reaching based on the difficulty of future actions – To what extent can infants’ multiple step actions be explained by Fitts’ law?

Prospective motor control, a key element of action planning, is the ability to adjust one’s actions with respect to task demands and action goals in an anticipatory manner. The current study investigates whether 14-month-olds are able to prospectively control their reaching actions based on the difficulty of the subsequent action. We used a reach-to-place task, with difficulty of the placing action varied by goal size and goal distance. To target prospective motor control, we determined the kinematics of the prior reaching movements using a motion-tracking system. Peak velocity of the first movement unit of the reach served as indicator for prospective motor control. Both difficulty aspects (goal size and goal distance) affected prior reaching, suggesting that both these aspects of the subsequent action have an impact on the prior action. The smaller the goal size and the longer the distance to the goal, the slower infants were in the beginning of their reach towards the object. Additionally we modeled movement times of both reaching and placing actions using a formulation of Fitts’ law. The model was significant for placement and reaching movement times. These findings suggest that 14-month-olds are able to plan their future actions and prospectively control their related movements with respect to future task difficulties.

Measuring Prospective Motor Control in Action Development

This article critically reviews kinematic measures of prospective motor control. Prospective motor control, the ability to anticipatorily adjust movements with respect to task demands and action goals, is an important process involved in action planning. In manual object manipulation tasks, prospective motor control has been studied in various ways, mainly using motion tracking. For this matter, it is crucial to pinpoint the early part of the movement that purely reflects prospective (feed-forward) processes, but not feedback influences from the unfolding movement. One way of defining this period is to rely on a fixed time criterion; another is to base it flexibly on the inherent structure of each movement itself. Velocity—as one key characteristic of human movement—offers such a possibility and describes the structure of movements in a meaningful way. Here, I argue for the latter way of investigating prospective motor control by applying the measure of peak velocity of the first movement unit. I further discuss movement units and their significance in motor development of infants and contrast the introduced measure with other measures related to peak velocity and duration.

Measuring Prospective Motor Control in Action Development

This article critically reviews kinematic measures of prospective motor control. Prospective motor control, the ability to anticipatorily adjust movements with respect to task demands and action goals, is an important process involved in action planning. In manual object manipulation tasks, prospective motor control has been studied in various ways, mainly using motion tracking. For this matter, it is crucial to pinpoint the early part of the movement that purely reflects prospective (feed-forward) processes, but not feedback influences from the unfolding movement. One way of defining this period is to rely on a fixed time criterion; another is to base it flexibly on the inherent structure of each movement itself. Velocity—as one key characteristic of human movement—offers such a possibility and describes the structure of movements in a meaningful way. Here, I argue for the latter way of investigating prospective motor control by applying the measure of peak velocity of the first movement unit. I further discuss movement units and their significance in motor development of infants and contrast the introduced measure with other measures related to peak velocity and duration.