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Using visual feedback distortion to alter coordinated pinching patterns for robotic rehabilitation.

Matsuoka Y, Brewer BR, Klatzky RL - J Neuroeng Rehabil (2007)

Bottom Line: Fifty-one able-bodied subjects participated in the study.During the experiment, each subject learned to move their index finger and thumb in a particular target pattern while receiving visual feedback.This study marks the first investigation on multi-finger coordination tasks under visual feedback manipulation.

View Article: PubMed Central - HTML - PubMed

Affiliation: The Robotics Institute, Carnegie Mellon University, Pittsburgh, PA 15213, USA. yoky@cs.cmu.edu

ABSTRACT

Background: It is common for individuals with chronic disabilities to continue using the compensatory movement coordination due to entrenched habits, increased perception of task difficulty, or personality variables such as low self-efficacy or a fear of failure. Following our previous work using feedback distortion in a virtual rehabilitation environment to increase strength and range of motion, we address the use of visual feedback distortion environment to alter movement coordination patterns.

Methods: Fifty-one able-bodied subjects participated in the study. During the experiment, each subject learned to move their index finger and thumb in a particular target pattern while receiving visual feedback. Visual distortion was implemented as a magnification of the error between the thumb and/or index finger position and the desired position. The error reduction profile and the effect of distortion were analyzed by comparing the mean total absolute error and a normalized error that measured performance improvement for each subject as a proportion of the baseline error.

Results: The results of the study showed that (1) different coordination pattern could be trained with visual feedback and have the new pattern transferred to trials without visual feedback, (2) distorting individual finger at a time allowed different error reduction profile from the controls, and (3) overall learning was not sped up by distorting individual fingers.

Conclusion: It is important that robotic rehabilitation incorporates multi-limb or finger coordination tasks that are important for activities of daily life in the near future. This study marks the first investigation on multi-finger coordination tasks under visual feedback manipulation.

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Related in: MedlinePlus

Two PHANTOM™ robots were used to track and distort the index finger and thumb movement trajectories separately.
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Figure 1: Two PHANTOM™ robots were used to track and distort the index finger and thumb movement trajectories separately.

Mentions: The robotic environment used in this experiment is shown in Figure 1. One or two Premium 1.0 PHANTOM™ force-feedback robots (SensAble Technologies, Inc., Woburn, MA) were used. Each robot has 3 active degrees of freedom and a position resolution of 0.03 mm[11]. The standard finger cuff provided by Sensable Technologies provided additional 3 passive degrees of freedom at the fingertip. For the conditions involved two fingers, the subject placed the index finger in one finger cuff and the thumb in the other. For the conditions involved only the thumb, the subject placed only the thumb in a robot. The other fingers grasped a post to keep the hand stationary throughout the experiment. The subject sat with the arm flexed at the elbow and the forearm horizontal.


Using visual feedback distortion to alter coordinated pinching patterns for robotic rehabilitation.

Matsuoka Y, Brewer BR, Klatzky RL - J Neuroeng Rehabil (2007)

Two PHANTOM™ robots were used to track and distort the index finger and thumb movement trajectories separately.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC1904454&req=5

Figure 1: Two PHANTOM™ robots were used to track and distort the index finger and thumb movement trajectories separately.
Mentions: The robotic environment used in this experiment is shown in Figure 1. One or two Premium 1.0 PHANTOM™ force-feedback robots (SensAble Technologies, Inc., Woburn, MA) were used. Each robot has 3 active degrees of freedom and a position resolution of 0.03 mm[11]. The standard finger cuff provided by Sensable Technologies provided additional 3 passive degrees of freedom at the fingertip. For the conditions involved two fingers, the subject placed the index finger in one finger cuff and the thumb in the other. For the conditions involved only the thumb, the subject placed only the thumb in a robot. The other fingers grasped a post to keep the hand stationary throughout the experiment. The subject sat with the arm flexed at the elbow and the forearm horizontal.

Bottom Line: Fifty-one able-bodied subjects participated in the study.During the experiment, each subject learned to move their index finger and thumb in a particular target pattern while receiving visual feedback.This study marks the first investigation on multi-finger coordination tasks under visual feedback manipulation.

View Article: PubMed Central - HTML - PubMed

Affiliation: The Robotics Institute, Carnegie Mellon University, Pittsburgh, PA 15213, USA. yoky@cs.cmu.edu

ABSTRACT

Background: It is common for individuals with chronic disabilities to continue using the compensatory movement coordination due to entrenched habits, increased perception of task difficulty, or personality variables such as low self-efficacy or a fear of failure. Following our previous work using feedback distortion in a virtual rehabilitation environment to increase strength and range of motion, we address the use of visual feedback distortion environment to alter movement coordination patterns.

Methods: Fifty-one able-bodied subjects participated in the study. During the experiment, each subject learned to move their index finger and thumb in a particular target pattern while receiving visual feedback. Visual distortion was implemented as a magnification of the error between the thumb and/or index finger position and the desired position. The error reduction profile and the effect of distortion were analyzed by comparing the mean total absolute error and a normalized error that measured performance improvement for each subject as a proportion of the baseline error.

Results: The results of the study showed that (1) different coordination pattern could be trained with visual feedback and have the new pattern transferred to trials without visual feedback, (2) distorting individual finger at a time allowed different error reduction profile from the controls, and (3) overall learning was not sped up by distorting individual fingers.

Conclusion: It is important that robotic rehabilitation incorporates multi-limb or finger coordination tasks that are important for activities of daily life in the near future. This study marks the first investigation on multi-finger coordination tasks under visual feedback manipulation.

Show MeSH
Related in: MedlinePlus