 |
||||
|
||||
|
||||
|
||||
The Journal of Neuroscience, October 8, 2003, 23(27):9032-9045
Previous Article | Next Article
Behavioral/Systems/Cognitive
Quantifying Generalization from Trial-by-Trial Behavior of Adaptive Systems that Learn with Basis Functions: Theory and Experiments in Human Motor Control
Opher Donchin, Joseph T. Francis, andReza Shadmehr Laboratory for Computational Motor Control, Department of Biomedical Engineering, Johns Hopkins School of Medicine, Baltimore, Maryland 21205
During reaching movements, the brain's internal models map desired limb motion into predicted forces. When the forces in the task change, these models adapt. Adaptation is guided by generalization: errors in one movement influence prediction in other types of movement. If the mapping is accomplished with population coding, combining basis elements that encode different regions of movement space, then generalization can reveal the encoding of the basis elements. We present a theory that relates encoding to generalization using trial-by-trial changes in behavior during adaptation. We consider adaptation during reaching movements in various velocity-dependent force fields and quantify how errors generalize across direction. We find that the measurement of error is critical to the theory. A typical assumption in motor control is that error is the difference between a current trajectory and a desired trajectory (DJ) that does not change during adaptation. Under this assumption, in all force fields that we examined, including one in which force randomly changes from trial to trial, we found a bimodal generalization pattern, perhaps reflecting basis elements that encode direction bimodally. If the DJ was allowed to vary, bimodality was reduced or eliminated, but the generalization function accounted for nearly twice as much variance. We suggest, therefore, that basis elements representing the internal model of dynamics are sensitive to limb velocity with bimodal tuning; however, it is also possible that during adaptation the error metric itself adapts, which affects the implied shape of the basis elements.
Key words: adaptation; motor learning; system identification; receptive field; psychophysics; model
Received April 1, 2003; revised July 23, 2003; accepted July 30, 2003.
This article has been cited by other articles:
M. Casadio, V. Sanguineti, P. Morasso, and C. Solaro
Abnormal sensorimotor control, but intact force field adaptation, in multiple sclerosis subjects with no clinical disability
Multiple Sclerosis, April 1, 2008; 14(3): 330 - 342.
[Abstract] [PDF]
J. Izawa, T. Rane, O. Donchin, and R. Shadmehr
Motor Adaptation as a Process of Reoptimization
J. Neurosci., March 12, 2008; 28(11): 2883 - 2891.
[Abstract] [Full Text] [PDF]
S. Tremblay, G. Houle, and D. J. Ostry
Specificity of Speech Motor Learning
J. Neurosci., March 5, 2008; 28(10): 2426 - 2434.
[Abstract] [Full Text] [PDF]
R. Srimal, J. Diedrichsen, E. B. Ryklin, and C. E. Curtis
Obligatory Adaptation of Saccade Gains
J Neurophysiol, March 1, 2008; 99(3): 1554 - 1558.
[Abstract] [Full Text] [PDF]
A. A. G. Mattar and D. J. Ostry
Modifiability of Generalization in Dynamics Learning
J Neurophysiol, December 1, 2007; 98(6): 3321 - 3329.
[Abstract] [Full Text] [PDF]
M. C. Simani, L. M. M. McGuire, and P. N. Sabes
Visual-Shift Adaptation Is Composed of Separable Sensory and Task-Dependent Effects
J Neurophysiol, November 1, 2007; 98(5): 2827 - 2841.
[Abstract] [Full Text] [PDF]
M. Casadio, V. Sanguineti, C. Solaro, and P. G. Morasso
A Haptic Robot Reveals the Adaptation Capability of Individuals with Multiple Sclerosis
The International Journal of Robotics Research, November 1, 2007; 26(11-12): 1225 - 1233.
[Abstract] [PDF]
M. S. Fine and K. A. Thoroughman
Trial-by-Trial Transformation of Error Into Sensorimotor Adaptation Changes With Environmental Dynamics
J Neurophysiol, September 1, 2007; 98(3): 1392 - 1404.
[Abstract] [Full Text] [PDF]
D. Liu and E. Todorov
Evidence for the Flexible Sensorimotor Strategies Predicted by Optimal Feedback Control
J. Neurosci., August 29, 2007; 27(35): 9354 - 9368.
[Abstract] [Full Text] [PDF]
Y.-w. Tseng, J. Diedrichsen, J. W. Krakauer, R. Shadmehr, and A. J. Bastian
Sensory Prediction Errors Drive Cerebellum-Dependent Adaptation of Reaching
J Neurophysiol, July 1, 2007; 98(1): 54 - 62.
[Abstract] [Full Text] [PDF]
J. L. Emken, R. Benitez, A. Sideris, J. E. Bobrow, and D. J. Reinkensmeyer
Motor Adaptation as a Greedy Optimization of Error and Effort
J Neurophysiol, June 1, 2007; 97(6): 3997 - 4006.
[Abstract] [Full Text] [PDF]
V. S. Huang and R. Shadmehr
Evolution of Motor Memory During the Seconds After Observation of Motor Error
J Neurophysiol, June 1, 2007; 97(6): 3976 - 3985.
[Abstract] [Full Text] [PDF]
J. Diedrichsen, T. Verstynen, A. Hon, Y. Zhang, and R. B. Ivry
Illusions of Force Perception: The Role of Sensori-Motor Predictions, Visual Information, and Motor Errors
J Neurophysiol, May 1, 2007; 97(5): 3305 - 3313.
[Abstract] [Full Text] [PDF]
S. Cheng and P. N. Sabes
Calibration of Visually Guided Reaching Is Driven by Error-Corrective Learning and Internal Dynamics
J Neurophysiol, April 1, 2007; 97(4): 3057 - 3069.
[Abstract] [Full Text] [PDF]
R. A. Scheidt and T. Stoeckmann
Reach Adaptation and Final Position Control Amid Environmental Uncertainty After Stroke
J Neurophysiol, April 1, 2007; 97(4): 2824 - 2836.
[Abstract] [Full Text] [PDF]
H. Chen, S. E. Hua, M. A. Smith, F. A. Lenz, and R. Shadmehr
Effects of Human Cerebellar Thalamus Disruption on Adaptive Control of Reaching
Cereb Cortex, October 1, 2006; 16(10): 1462 - 1473.
[Abstract] [Full Text] [PDF]
T. E. Milner and M. R. Hinder
Position Information But Not Force Information Is Used in Adapting to Changes in Environmental Dynamics
J Neurophysiol, August 1, 2006; 96(2): 526 - 534.
[Abstract] [Full Text] [PDF]
M. S. Fine and K. A. Thoroughman
Motor Adaptation to Single Force Pulses: Sensitive to Direction but Insensitive to Within-Movement Pulse Placement and Magnitude
J Neurophysiol, August 1, 2006; 96(2): 710 - 720.
[Abstract] [Full Text] [PDF]
S. Cheng and P. N. Sabes
Modeling sensorimotor learning with linear dynamical systems.
Neural Comput., April 1, 2006; 18(4): 760 - 793.
[Abstract] [Full Text] [PDF]
C. D. Takahashi, D. Nemet, C. M. Rose-Gottron, J. K. Larson, D. M. Cooper, and D. J. Reinkensmeyer
Effect of muscle fatigue on internal model formation and retention during reaching with the arm
J Appl Physiol, February 1, 2006; 100(2): 695 - 706.
[Abstract] [Full Text] [PDF]
R. Paz, C. Natan, T. Boraud, H. Bergman, and E. Vaadia
Emerging Patterns of Neuronal Responses in Supplementary and Primary Motor Areas during Sensorimotor Adaptation
J. Neurosci., November 23, 2005; 25(47): 10941 - 10951.
[Abstract] [Full Text] [PDF]
J. Diedrichsen, Y. Hashambhoy, T. Rane, and R. Shadmehr
Neural Correlates of Reach Errors
J. Neurosci., October 26, 2005; 25(43): 9919 - 9931.
[Abstract] [Full Text] [PDF]
K. A. Thoroughman and J. A. Taylor
Rapid Reshaping of Human Motor Generalization
J. Neurosci., September 28, 2005; 25(39): 8948 - 8953.
[Abstract] [Full Text] [PDF]
T. E. Milner and D. W. Franklin
Impedance control and internal model use during the initial stage of adaptation to novel dynamics in humans
J. Physiol., September 1, 2005; 567(2): 651 - 664.
[Abstract] [Full Text] [PDF]
J. Trommershauser, S. Gepshtein, L. T. Maloney, M. S. Landy, and M. S. Banks
Optimal Compensation for Changes in Task-Relevant Movement Variability
J. Neurosci., August 3, 2005; 25(31): 7169 - 7178.
[Abstract] [Full Text] [PDF]
M. A. Smith and R. Shadmehr
Intact Ability to Learn Internal Models of Arm Dynamics in Huntington's Disease But Not Cerebellar Degeneration
J Neurophysiol, May 1, 2005; 93(5): 2809 - 2821.
[Abstract] [Full Text] [PDF]
S. K. Wainscott, O. Donchin, and R. Shadmehr
Internal Models and Contextual Cues: Encoding Serial Order and Direction of Movement
J Neurophysiol, February 1, 2005; 93(2): 786 - 800.
[Abstract] [Full Text] [PDF]
K. P. Kording and D. M. Wolpert
The loss function of sensorimotor learning
PNAS, June 29, 2004; 101(26): 9839 - 9842.
[Abstract] [Full Text] [PDF]
|
|
|
|
 |
|