Simulating closed- and open-loop voluntary movement: a nonlinear control-systems approach.
IEEE Trans Biomed Eng
; 49(11): 1242-52, 2002 Nov.
Article
en En
| MEDLINE
| ID: mdl-12450354
In many recent human motor control models, including feedback-error learning and adaptive model theory (AMT), feedback control is used to correct errors while an inverse model is simultaneously tuned to provide accurate feedforward control. This popular and appealing hypothesis, based on a combination of psychophysical observations and engineering considerations, predicts that once the tuning of the inverse model is complete the role of feedback control is limited to the correction of disturbances. This hypothesis was tested by looking at the open-loop behavior of the human motor system during adaptation. An experiment was carried out involving 20 normal adult subjects who learned a novel visuomotor relationship on a pursuit tracking task with a steering wheel for input. During learning, the response cursor was periodically blanked, removing all feedback about the external system (i.e., about the relationship between hand motion and response cursor motion). Open-loop behavior was not consistent with a progressive transfer from closed- to open-loop control. Our recently developed computational model of the brain--a novel nonlinear implementation of AMT--was able to reproduce the observed closed- and open-loop results. In contrast, other control-systems models exhibited only minimal feedback control following adaptation, leading to incorrect open-loop behavior. This is because our model continues to use feedback to control slow movements after adaptation is complete. This behavior enhances the internal stability of the inverse model. In summary, our computational model is currently the only motor control model able to accurately simulate the closed- and open-loop characteristics of the experimental response trajectories.
Buscar en Google
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Desempeño Psicomotor
/
Dinámicas no Lineales
/
Retroalimentación
/
Aprendizaje
/
Modelos Biológicos
/
Movimiento
Tipo de estudio:
Diagnostic_studies
/
Prognostic_studies
Límite:
Female
/
Humans
/
Male
Idioma:
En
Revista:
IEEE Trans Biomed Eng
Año:
2002
Tipo del documento:
Article
País de afiliación:
Nueva Zelanda
Pais de publicación:
Estados Unidos