The effect of concurrent hand movement on estimated time to contact in a prediction motion task.

In many activities, we need to predict the arrival of an occluded object. This action is called prediction motion or motion extrapolation. Previous researchers have found that both eye tracking and the internal clocking model are involved in the prediction motion task.

Inter-limb coordination and control in boys with and without DCD in ball catching.

The purpose of the study was to examine the nature of inter-limb coordination and control, exhibited by ten boys with (M=10.5 years, SD=1.0) and without Developmental Coordination Disorder (DCD), in a ball catching task across different ball speeds.

Nature of spatial coupling in children with and without developmental coordination disorder in ball catching.

The nature of intra- and interlimb (bimanual) coordination was examined in ten boys with (M = 10.5 years, SD = 1.0) and without DCD (M = 10.

Movement coordination in ball catching: comparison between boys with and without developmental coordination disorder.

This investigation examined the catching coordination of 12 boys (M age = 9.9 years, SD = .8) with and without Developmental Coordination Disorder (DCD; M age = 10.

"Go" signal intensity influences the sprint start.

Introduction: Loud sounds can decrease reaction time (RT) and increase force generated during voluntary contractions. Accordingly, we hypothesized that the loud starter's pistol at the Olympic Games allows runners closer to the starter to react sooner and stronger than runners farther away.

Methods: RT for the 100/110 m athletics events at the 2004 Olympics were obtained from International Association of Athletics Federations archives and binned by lane.

Gross motor skill acquisition in adolescents with Down syndrome.

The purpose of this study was to assess whether verbal-motor performances deficits exhibited by individuals with Down syndrome limited their ability to acquire gross motor skills when given visual and verbal instruction together and then transferred to either a visual or verbal instructional mode to reproduce the movement. Nine individuals with Down syndrome (6 males, 3 females) performed 3 gross motor skills. Both visual and verbal instructional guidance was given to the participants over a 4-day period.

Perceptual judgments for stair climbing as a function of pitch angle.

Two experiments explored perception and action for stair climbing, with manipulations to the stair dimensions. In Experiment 1, a custom-built apparatus manipulated the stair dimensions, while three groups of participants made perceptual judgments of climbability. The groups differed significantly for absolute leg length (p < .

Bimanual coordination dynamics in adults with Down syndrome.

Previous experiments involving discrete unimanual tasks have shown that individuals with Down syndrome (DS) have auditory/verbal-motor deficits. The present study investigated unimanual and bimanual continuous perceptual-motor actions in adults with DS. Ten adults with DS, 10 typical adults, and 10 children drew continuous circles at increasing periods bimanually and unimanually with each hand.

Auditory information is beneficial for adults with Down syndrome in a continuous bimanual task.

Much recent research using discrete unimanual tasks has indicated that individuals with Down syndrome (DS) have more difficulty performing verbal-motor tasks as compared to visual-motor tasks (see Perceptual-Motor Behavior in Down Syndrome, Human Kinetics, Champaign, IL, 2000, p. 305 for a review). In continuous tasks, however, individuals with DS perform better when movement is guided by auditory information compared to visual information (Downs Syndr.

A kinematic analysis of high-speed treadmill sprinting over a range of velocities.

Introduction: The purpose of this study was to measure changes in stride characteristics and lower-extremity kinematics of the hip and knee as a function of increasing treadmill velocity, at velocities ranging from submaximal to near maximal.

Methods: Six power/speed athletes experienced at sprinting on a treadmill performed trials at 70%, 80%, 90%, and 95% of their previous individual maximum velocity, with video data collected in the sagittal view at 60 Hz.

Results: Significant differences were seen in stride frequency (70%, 80%, P < 0.