Search Results

You are looking at 1 - 3 of 3 items for

  • Author: Charles Shea x
  • Refine by Access: All Content x
Clear All Modify Search
Restricted access

Dyad Training in a Perceptual-Motor Task: “Two Pairs of Eyes Are Better Than One”

Stefan Panzer, Christina Pfeifer, Peter Leinen, and Charles Shea

The aim of this experiment was to determine if dyad practice helped individuals become aware, use, and retain information in a dynamically changing perceptual-motor task compared with practice alone. We used a computerized perceptual-motor task, where individuals were required to intercept balls that dropped from the top of the screen. A colored line at the top of the screen provided information about the direction of the dropping ball. Participants (N = 24) were randomly assigned to one of two groups: A dyad training group where two participants alternated between physical and observational practice after each block of 20 trials, and they also engaged in dialog about the task, and an individual training group where one participant practiced the task. Both groups improved their accuracy during acquisition. On the retention test, participants in the dyad group caught significantly more balls (73%) than individuals of the alone group (58%). Participants in the dyad group also showed a higher percentage of correctly identified stimuli in the recognition task. Dyad training induced performance advantages in a perceptual-motor task because individuals became aware and used information acquired during observation and/or from the dialog.

Restricted access

Optimizing the Control of High Index of Difficulty Movements: The Role of the Tracking Template

Jason B. Boyle, Deanna M. Kennedy, Chaoyi Wang, and Charles Shea

An experiment by Boyle, Kennedy, and Shea (2012) demonstrated that practice tracking a template created from a sine wave results in enhanced performance and transfer on a reciprocal aiming task with an index of difficulty (ID) of 6. An experiment was conducted to determine whether tracking a template constructed from recorded participants' performance with ID = 6 would provide the same benefit. Participants were assigned to one of four groups (Fitts–master, Fitts–yoked, sine–master, and sine–yoked). After acquisition, visual templates were constructed for the Fitts–yoked and sine–yoked conditions. The templates were generated from the unique displacement data of the Fitts– and sine–master participants. These made up the training template for the Fitts– and sine–yoked participants. After acquisition, all participants were asked to perform test trials under their respective acquisition conditions (Test 1) and test trials under ID = 6 reciprocal aiming conditions (Test 2). Results indicated faster movement times in the sine-wave training groups on Test 2 than in both Fitts groups. These results indicate that the presentation of a tracking template can result in lower dwell times in the Fitts–yoked pairing on Test 2. However, the findings indicate the need to use templates that guide the movement in a way that promotes an equal acceleration–deceleration profile paired with smooth target reversal.

Restricted access

Validity of Anthropometry and Bioimpedance with 4- to 8-Year-Olds Using Total Body Water as the Criterion

Mollie G. DeLozier, Bernard Gutin, Jack Wang, Charles E. Basch, Isobel Contento, Steven Shea, Matilde Irigoyen Patricia Zybert, Jill Rips, and Richard Pierson

Anthropometric and bioimpedance regression equations were developed for young children using total body water (TBW) as the criterion. Ninety-six boys and girls, 4-8 years of age, served as subjects. Measures included height, weight, five skinfold thicknesses, three circumferences, total body bioimpedance, and separate bioimpedance measures of the arm, trunk, and leg. Height and weight alone accounted for .70 of the variance in TBW. Adding other measures did not significantly increase the R 2. Standard errors of estimate for TBW were similar to those reported for older individuals (1.39-1.44 1) but may be too large relative to the small size of the subjects for the equations to be acceptable.