Related Experiment Videos
Limb position drift: implications for control of posture and movement
Liana E Brown1, David A Rosenbaum, Robert L Sainburg
1Department of Psychology, Pennsylvania State University, University Park, Pennsylvania 16802, USA. lbrown38@uwo.ca
Journal of Neurophysiology
|November 15, 2003
Summary
Proprioception, the sense of limb position, remains reliable without vision. Despite hand position drift during repetitive movements, accuracy in distance and direction is maintained through muscle adjustments.
Area of Science:
- Neuroscience
- Motor Control
- Human Movement Science
Background:
- Proprioceptive drift occurs without visual feedback, potentially reducing limb position accuracy.
- This drift is hypothesized to stem from decreased proprioceptive reliability over time.
Purpose of the Study:
- To investigate if proprioceptive drift degrades movement accuracy (distance and direction) during prolonged absence of visual feedback.
- To examine the relationship between movement production and drift in limb position.
Main Methods:
- Participants performed repetitive movements without visual feedback after initial calibration.
- Movements were executed in series, with fingertip feedback removed after initial trials.
- Analysis included measuring hand position drift and movement accuracy, alongside inverse dynamics of joint torques.
Main Results:
- Significant drift in hand and start location (average 8 cm) was observed over 70 trials without visual feedback.
- Movement distance and direction accuracy remained relatively constant despite the drift.
- Movement preservation correlated with significant modifications in joint muscle torque.
Conclusions:
- Proprioception remains a reliable source of limb position information even after extended periods without visual input.
- The central nervous system utilizes proprioceptive information differently for maintaining limb position versus specifying movement trajectories.