72x36 Poster Template - University of Central Florida

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Transcript 72x36 Poster Template - University of Central Florida

Learning Effect With Repeated Use of the DynaVision D2 Visual Motor Evaluation William P. McCormack, Nadia S. Emerson, David R. Williams, Adam J. Wells, Gerald T. Mangine, Adam M. Gonzalez, Maren S. Fragala, Jay R. Hoffman, FACSM

Human Performance Laboratory, University of Central Florida, Orlando, FL

ABSTRACT

PURPOSE: The purpose of this study was to examine the effect of repeated trials on performance improvements using the Dynavision™ D2 reaction device. METHODS: Twenty-one female division I college athletes (10 basketball and 11 volleyball) performed hand-eye reaction time tests of peripheral vision (PV), peripheral vision with number recall (PVNR), and visual-reaction (VR) on the Dynavision TM D2 (Dynavision, Ontario Canada). The PV and PVNR tests measured accuracy (hits) in reacting to light stimuli for one minute duration. The VR measured time in reacting to 5 separate visual stimuli with the dominant and non-dominant hands. Each volunteer completed four trials of each test. Differences between subsequent trials were analyzed with one-way repeated measures ANOVA. RESULTS: Significant improvements in PV were seen between T1 (69.3 ± 7.8 hits), T2 (77.4 ± 12.5 hits), and T3 (82.3 ± 7.6 hits). There was no significant improvement between T3 and T4 (84.9 ± 9.5 hits). In the PVNR, no significant differences were seen between T1 (61.6 ± 11.0 hits), T2 (63.4 ± 14.3 hits), and T3 (67.3 ± 12.6 hits). However, there was significant improvement between T3 and T4 (75.2 ± 11.9 hits). The only significant difference in VR was in Trial 2 in both the dominant (T2: 0.422 ± 0.042 and T4: 0.390 ± 0.039 sec) and non-dominant hand (T2: 0.445 ± 0.093 and T4: 0.378 ± 0.029 sec) in visual reaction time. There was no significant difference in motor reaction time in the four trials in either hand.

CONCLUSION: Results indicate that competitive athletes should perform three trials to achieve baseline performance measures in PV. However, as the complexity of the task increases as with the PVNR, at least a fourth trial is necessary. In addition, both visual and motor reaction time does appear to be consistent with each testing trial, suggesting that there is a limited learning effect in VR observed during consecutive testing trials when assessing competitive athletes.

INTRODUCTION

Recently a light-training reaction device has been developed to enhance sensory motor integration with the purpose of improving athletic performance. It has also been suggested that this system can serve as an evaluation tool for concussions and visual-field deficits that can provide information for a team’s medical staff on issues related to return to play. However, in these circumstances it becomes critical to determine how many trials are needed to achieve a true baseline measure

PURPOSE

The purpose of this study was to examine the effect of repeated trials on performance improvements using the Dynavision™ D2 reaction device.

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METHODS Subjects

Twenty-one, female division I college athletes performed three different hand-eye reaction time tests over a two week period.

Device Set-up

The board was adjusted to each subject by setting the LCD screen just below eye level. Subjects were instructed to back away from the board until all the lights were visible in their peripheral vision and they could still reach all the lights.

• • •

The Tests

Peripheral Vision (PV) test: Any of the 64 lights is lit until the subject touches the light at which time a new light will illuminate. Objective: Hit as many lights as possible during 60 seconds.

Peripheral Vision with Number Recall (PVNR): Any of the 64 lights is lit for 1 second and every 5 seconds a 5-digit number appears in the LCD window for 1 second. Objective: Hit as many lights as possible while verbally stating the 5 digit number.

Visual-Reaction (VR) test: The 5 horizontal lights to the left of the center ring are utilized. Upon start of the test, any of the 5-lights will illuminate and the subject has to move the hand from the starting position, hit the illuminated light and return to the starting position.

• •

Measures

During the PV and PVNR tests, the number of hits per 60 seconds is counted as the score.

During the VR test, the average visual speed (time to see the target and initiate a response) and average motor speed (the time it takes to physically respond to the target, after the initial visual reaction). A Samsung N150 computer was used to record all measures.

Analysis

A repeated measures Analysis of Variance (ANOVA) was utilized to compare the means for each test over the four trials.

The DynaVision TM D2, is a light-training reaction device, developed to train sensory motor integration through the visual system. There are 64, 15 x 15mm square lights arranged in 5 concentric circles.

RESULTS PV Test

Significant improvements in PV were seen between T1 (69.3 ± 7.8 hits), T2 (77.4 ± 12.5 hits), and T3 (82.3 ± 7.6 hits). There was no significant improvement between T3 and T4 (84.9 ± 9.5 hits), Figure 1.

* +

Figure 1. PV Results (Mean hits ± SE)

*

= T2 significantly better than T1

+

= T3 significantly better than T2

PVNR Test

No significant differences were seen between T1 (61.6 ± 11.0 hits), T2 (63.4 ± 14.3 hits), and T3 (67.3 ± 12.6 hits). However, there was significant improvement between T3 and T4 (75.2 ± 11.9 hits), Figure 2.

*

Figure 2. PVNR Results (Mean hits ± SE)

*

= T4 was significantly better than T3

RESULTS (CONT.)

• • • •

VR Test

In the VR tests, there were no significant differences between dominant and non-dominant hands across the trials.

The only significant difference in the VR tests across the left hand trials was between T2 (0.445 ± 0.029 sec) and T4 (0.378 ± 0.029 sec). The only significant difference in the VR tests across the right hand trials was between T2 (0.422 ± 0.013 sec) and T4 (0.390 ± 0.012 sec). There was no significant difference in motor reaction time between hands or across the four trials. Table 1.

Trial 1 Trial 2 Trial 3 Trial 4 LH Visual 0.391 ± 0.019

0.445 ± 0.029* 0.390 ± 0.015

RH Visual 0.404 ± 0.020

0.422 ± 0.013* 0.450 ± 0.026

LH Motor 0.403 ± 0.042

0.372 ± 0.037

0.375 ± 0.027

RH Motor 0.374 ± 0.032

0.373 ± 0.039

0.378 ± 0.052

0.378 ± 0.009* 0.390 ± 0.012* 0.365 ± 0.025

0.337 ± 0.017

Table 1. Reaction Test Results (Mean ± SE)

* = T2 significantly slower than T4

SUMMARY & CONCLUSIONS

Results indicate that competitive athletes should perform three trials to achieve baseline performance measures in the PV test. However, as the complexity of the task increases as in the PVNR, at least a fourth trial is necessary. In addition, both visual and motor reaction time does appear to be consistent with each testing trial, suggesting that there is a limited learning effect in VR observed during consecutive testing trials when assessing competitive athletes.