Hierarchical control of two-dimensional gaze saccades
Coordinating the movements of different body parts is a challenging process for the central nervous system because of several problems. Four of these main difficulties are: first, moving one part can move others; second, the parts can have different dynamics; third, some parts can have different motor goals; and fourth, some parts may be perturbed by outside forces. Here, we propose a novel approach for the control of linked systems with feedback loops for each part. The proximal parts have separate goals, but critically the most distal part has only the common goal. We apply this new control policy to eye-head coordination in two-dimensions, specifically head-unrestrained gaze saccades. Paradoxically, the hierarchical structure has controllers for the gaze and the head, but not for the eye (the most distal part). Our simulations demonstrate that the proposed control structure reproduces much of the published empirical data about gaze movements, e.g., it compensates for perturbations, accurately reaches goals for gaze and head from arbitrary initial positions, simulates the nine relationships of the head-unrestrained main sequence, and reproduces observations from lesion and single-unit recording experiments. We conclude by showing how our model can be easily extended to control structures with more linked segments, such as the control of coordinated eye on head on trunk movements.
KeywordsGaze saccades Eye Head Feedback control Superior colliculus VOR suppression
Drs. Optican and Daye were supported by the Intramural Research Program of the National Eye Institute.
Dr. Blohm has been supported by the National Science and Engineering Research Council (Canada), the Ontario Research Fund (Canada), the Canadian Foundation for Innovation (Canada) and the Botterell Foundation (Queens University, Kingston, ON, Canada).
Dr. Lefevre has been supported by Fonds National de la Recherche Scientifique, Action de Recherche Concertée (Belgium). This paper presents research results of the Belgian Network Dynamical Systems, Control and Optimization, funded by the Interuniversity Attraction Poles Programmes, initiated by the Belgian State, Science Policy Office.
Conflict of interests
The authors declare that they have no conflict of interest
- Goffart, L., Guillaume, A., Pélisson, D. (1998a). Compensation for gaze perturbation during inactivation of the caudal fastigial nucleus in the head-unrestrained cat. Journal of Neurophysiology, 80(3), 1552–1557.Google Scholar
- Goffart, L., Pélisson, D., Guillaume, A. (1998b). Orienting gaze shifts during muscimol inactivation of caudal fastigial nucleus in the cat. II. Dynamics and eye-head coupling. Journal of Neurophysiology, 79(4), 1959–1976.Google Scholar
- Guitton, D., & Volle, M. (1987a). Gaze control in humans: eye-head coordination during orienting movements to targets within and beyond the oculomotor range. Journal of Neurophysiology, 58(3), 427–459.Google Scholar
- Guitton, D., & Volle, M. (1987b). Gaze control in humans: eye-head coordination during orienting movements to targets within and beyond the oculomotor range. Journal of Neurophysiology, 58(3), 427–459.Google Scholar
- Optican, L. (2009). Oculomotor system: models. In Encyclopedia of neuroscience (pp. 25–34). Oxford: Academic.Google Scholar
- Robinson, D.A. (1975). Oculomotor control signals. In G. Lennerstand & P. Bach-y-Rita (Eds.), Basic mechanisms of ocular motility and their clinical implications (Vol. 24, pp. 337–374). Pergamon Press.Google Scholar
- Tomlinson, R., & Bahra, P. (1986a). Combined eye-head gaze shifts in the primate. I. Metrics. Journal of Neurophysiology, 56(6), 1542–1557.Google Scholar
- Tomlinson, R., & Bahra, P. (1986b). Combined eye-head gaze shifts in the primate. II. Interactions between saccades and the vestibuloocular reflex. Journal of Neurophysiology, 56(6), 1558–1570.Google Scholar