Michael G. Wade

Decision and response times as a function of movement difficulty in preschool children

WALLACE, STEPHEN A.; NEWELL, KARL M.; and WADE, MICHAEL G. Decision and Response Times as a Function of Movement Difficulty in Preschool Children. CHILD DEVELOPMENT, 1978, 49, 509-512. This experiment determined whether the motor control of preschool children is affected by the amplitude and tolerance of movement. Using the Fitts paradigm, the reaction time (RT) and movement time (MT) to executive movements varying in difficulty were examined over 4 consecutive practice days. Results showed that the amplitude and tolerance of movement did not affect the RT required to initiate movement. However, MT was greatly affected by these variables in a manner predicted by Fittss Law. Also, the difficulty of movement appeared to affect MT of preschool children to a greater degree than that found previously with adults. Information-processing differences between children and adults were used as a tentative explanation for these results.

Nintendo Wii Balance Board is sensitive to effects of visual tasks on standing sway in healthy elderly adults

Research has shown that the Nintendo Wii Balance Board (WBB) can reliably detect the quantitative kinematics of the center of pressure in stance. Previous studies used relatively coarse manipulations (1- vs. 2-leg stance, and eyes open vs. closed). We sought to determine whether the WBB could reliably detect postural changes associated with subtle variations in visual tasks. Healthy elderly adults stood on a WBB while performing one of two visual tasks. In the Inspection task, they maintained their gaze within the boundaries of a featureless target. In the Search task, they counted the occurrence of designated target letters within a block of text. Consistent with previous studies using traditional force plates, the positional variability of the center of pressure was reduced during performance of the Search task, relative to movement during performance of the Inspection task. Using detrended fluctuation analysis, a measure of movement dynamics, we found that COP trajectories were more predictable during performance of the Search task than during performance of the Inspection task. The results indicate that the WBB is sensitive to subtle variations in both the magnitude and dynamics of body sway that are related to variations in visual tasks engaged in during stance. The WBB is an inexpensive, reliable technology that can be used to evaluate subtle characteristics of body sway in large or widely dispersed samples.

Visual tasks and postural sway in children with and without autism spectrum disorders

We investigated the influences of two different suprapostural visual tasks, visual searching and visual inspection, on the postural sway of children with and without autism spectrum disorder (ASD). Sixteen ASD children (age=8.75±1.34 years; height=130.34±11.03 cm) were recruited from a local support group. Individuals with an intellectual disability as a co-occurring condition and those with severe behavior problems that required formal intervention were excluded. Twenty-two sex- and age-matched typically developing (TD) children (age=8.93±1.39 years; height=133.47±8.21 cm) were recruited from a local public elementary school. Postural sway was recorded using a magnetic tracking system (Flock of Birds, Ascension Technologies, Inc., Burlington, VT). Results indicated that the ASD children exhibited greater sway than the TD children. Despite this difference, both TD and ASD children showed reduced sway during the search task, relative to sway during the inspection task. These findings replicate those of Stoffregen et al. (2000), Stoffregen, Giveans, et al. (2009), Stoffregen, Villard, et al. (2009) and Prado et al. (2007) and extend them to TD children as well as ASD children. Both TD and ASD children were able to functionally modulate postural sway to facilitate the performance of a task that required higher perceptual effort.

Themes in motor development

Section 1 Postural Control.- Postural Control and Development.- The Development of Proprioceptive Control.- Postural Control.- Section 2 Skill Development and Learning Disabilities.- Some Aspects of the Development of Motor Control in Downs Syndrome.- The Trainability of Motor Processing Strategies with Developmentally Delayed Performers.- Motor Dysfunctions in Children. Towards a Process-Oriented Diagnosis.- Information Processing and Motivation as Determinants of Performance in Children with Learning Disabilities.- Development of Coordination and Control in the Mentally Handicapped.- Manual Language: Its Relevance to Communication Acquisition in Autistic Children.- Section 3 The Development of Fine Motor Skills.- The Formation of the Finger Grip during Prehension a Cortically-Mediated Visuo-Motor Pattern.- Handwriting Disturbances: Developmental Trends.- Section 4 Perceptual and Cognitive Control of Motor Behaviour.- Normal and Abnormal Repetitive Stereotyped Behaviours.- Inhibitory Mechanisms in Childrens Skill Development.- Sensory-Motor Control and Balance: A Behavioural Perspective.- Section 5 Posture and Locomotion.- From Stepping to Adaptive Walking: Modulations of an Automatism.- Developmental Changes in the Relative Timing of Locomotion.- Section 6 Cultural Influences.- Motor Development and Cultural Attitudes.- The Acquisition of an Everyday Technical Motor Skill: The Pounding of Cereals in Mali.- Section 7 Speech & Language.- Parallels between Motor and Language Development.- Lateralisation and Motor Development.- Author Index.

Perceiving Affordances for Aperture Passage in an Environment–Person–Person System

ABSTRACT The authors investigated the perception of affordances for aperture passage in an environment–person–person (E–P–P) system, which comprised an adult perceiver and a child as a companion. Perceivers were 8 large and 8 small female undergraduates and were companioned with 1 large and 1 small girl. The perceivers perceptually judged the minimum aperture width for the E–P–P system, and then the adult–child dyads (a pair of people) actually walked through to determine the systems actual minimum aperture width. Results demonstrated that perceivers precisely judged the action capabilities of an E–P–P system on the basis of the body-scaled information of each adult–child dyad. The findings extended the previous concept of affordances for an environment-person system to affordances for an E–P–P system.

Coincidence anticipation of young normal and handicapped children.

Two coincident-timing experiments examined the role of three different target velocities and display extents and three age levels of normal and retarded children. Subjects made a ballistic response to a target moving horizontally across their visual field. In the first experiment there were generally no clear differences between normal and retarded children on the task, with subjects having difficulty for both the slow and fast target speeds. In the second experiment, with target velocity held constant, no significant differences were reported between normal and handicapped children, although the longer the subjects were allowed to view the target the more accurate they were. The data were discussed in terms of the response strategies to perform anticipatory ballistic movements. An ecological issue was raised which suggested that children as well as adults make their most accurate anticipations when confronted with velocity problems that have been experienced in their everyday world.

Postural responses to a suprapostural visual task among children with and without developmental coordination disorder

We sought to determine the effects of varying the perceptual demands of a suprapostural visual task on the postural activity of children with developmental coordination disorder (DCD), and typically developing children (TDC). Sixty-four (32 per group) children aged between 9 and 10 years participated. In a within-participants design, each child performed a signal detection task at two levels of difficulty, low (LD) and high difficulty (HD). During performance of the signal detection tasks we recorded positional variability of the head and torso using a magnetic tracking system. We found that task difficulty had a greater effect on task performance among the TDC group than among children with DCD. Overall positional variability was greater the DCD group than in the TDC group. In the TDC group, positional variability was reduced during performance of the HD task, relative to sway during performance of the LD task. In the DCD group, positional variability was greater during performance of the HD task than during performance of the LD task. In children, DCD may reduce the strength of functional integration of postural activity with the demands of suprapostural visual tasks.

Children at risk for developmental coordination disorder: judgement of changes in action capabilities

In three separate manipulations, a group of children at risk for developmental coordination disorder (DCD; five males, seven females; mean age 11y 6mo [SD 6.8mo]who were at or below the 15th centile on the Movement ABC) and a group of typically developing children (TDC; seven males, five females; mean age 11y 3mo [SD 6.8mo]) judged the limit of their standing horizontal reach (HRmax) under two conditions in which actual HRmax differed. The manipulations were: (1) one‐hand versus two‐hand reach; and (2) standard versus short effective foot‐length; and (3) rigid versus compliant support surface. For the foot‐length and support surface manipulations (but not for the hand manipulation), children correctly judged that their actual HRmax differed in the two conditions (p<.05). On all three manipulations, TDC made significantly larger adjustments in their judgements than did children at risk for DCD (p<0.05). The TDC group adjusted their judgements in the appropriate direction on all three manipulations, whereas the DCD group adjusted in the appropriate direction for the foot‐length manipulation only. The results suggest that children at risk for DCD are less adept at detecting changes in the limits of their action capabilities.

Postural Effects of the Horizon on Land and at Sea

Motion of a ship at sea creates challenges for control of the body. Anecdotal reports suggest that the body can be stabilized by standing on the open deck and looking at the horizon. This advice contrasts with land-based findings that looking at the horizon leads to increased body sway. We measured standing body sway in experienced maritime crew members on land and at sea. On land, body sway was greater when subjects looked at the horizon than when they did not—the classical effect. At sea, body sway was greater in a closed cabin than on the open deck. On the open deck, body sway when looking at the horizon was reduced relative to sway when looking at middistance targets on the ship. The results are consistent with centuries of anecdotal advice given to sea travelers and raise new questions about the referents that are used for the control of standing posture.

Dynamic and Static Balancing Ability of Preschool Children

Performance differences in dynamic and static balance ability of 150 preschool Ss aged 3,4, and 5 yr. were studied. Ss performed 4 balance-beam tasks and 2 balance-board tasks. An Age by Sex (3 × 2) factorial, design employing both univariate and multivariate ANOVA techniques were the statistics used. For both dynamic and static balance Age was highly significant, and the use of multivariate ANOVA indicated significant sex differences on the static balance tasks. The appropriateness of multivariate techniques where more than one dependent variable is measured on the same population was discussed, and the need to take into account the relationship between these variables when analyzing the data was noted.