Abstract
Little is known on how the brain derives a motor-command signal for initiating and directing a saccade from the visual information on the retina. Often two subsystems are distinguished. One system, called the WHERE system in this study, determines the metrics of saccades. Another system, denoted here as the WHEN system, initiates the saccade. An interesting property of the WHERE system was discovered by Becker and Jürgens (1979). They showed that saccades are directed at a delayed and filtered (or time-averaged) version of the stimulus trajectory. Several groups have observed rapid eye movements which abruptly changed course when the stimulus reversed direction. These responses have been interpreted as the sum of two separate saccades (Becker and Jürgens, 1979) or as a single saccade modified in midflight (Robinson, 1975). Recently Georgopoulos et al. (1981) found that hand-movement trajectories were curved while saccade trajectories were straight when monkeys tracked a stimulus which suddenly changed direction. Using essentially the same type of stimulus we did find curved saccade trajectories. Saccades to single step stimuli had approximately straight trajectories. These results are discussed in terms of a two-dimensional version of Robinson’s model.
Access this chapter
Tax calculation will be finalised at checkout
Purchases are for personal use only
Preview
Unable to display preview. Download preview PDF.
References
Barmack NH (1970) Modification of eye movements by instantaneous changes in the velocity of visual targets. Vision Res. 10, 1431–1441.
Becker W and Jürgens J (1979) An analysis of the saccadic system by means of double step stimuli. Vision Res. 19, 967–983.
Evinger C, Kaneko CRS and Fuchs AF (1981) Oblique saccadic eye movements of the cat. Exp. Brain Res. 41, 370–379.
Fuchs AF and Robinson DA (1966) A method for measuring horizontal and vertical eye movement chronically in the monkey. J. Appl. Physiol. 21, 1068–1070.
Georgopoulos AP, Kalaska JF and Massey JT (1981) Spatial trajectories and reaction times of aimed movements: effects of practice, uncertainty, and change in target location. J. Neurophysiol. 46, 725–743.
Gisbergen JAM van, Robinson DA and Gielen S (1981) A quantitative analysis of generation of saccadic eye movements by burst neurons. J. Neurophysiol. 45, 417–442.
Keller EL (1981) Brain stem mechanisms in saccadic control. In Progress in oculomotor research, eds. Fuchs AF and Becker W, pp 57–62. Elsevier North Holland, New York.
Mays LE and Sparks DL (1980) Dissociation of visual and saccade-related responses in superior colliculus neurons. J. Neurophysiol. 43, 207–232.
Reulen JPH (1982) The measurement of eye movement using double magnetic induction. IEEE Trans. Biomed. Eng. (accepted for publication).
Robinson DA (1975) Oculomotor control signals. In Basic Mechanisms of ocular motility and their clinical implications, ed. Lennerstrand G and Bach-y-Rita P, pp 337–374. Pergamon Press, Oxford.
Author information
Authors and Affiliations
Editor information
Editors and Affiliations
Rights and permissions
Copyright information
© 1982 Dr W. Junk Publishers, The Hague, Boston, London
About this paper
Cite this paper
van Gisbergen, J.A.M., Ottes, F.P., Eggermont, J.J. (1982). Responses of the Saccadic System to Sudden Changes in Target Direction. In: Roucoux, A., Crommelinck, M. (eds) Physiological and Pathological Aspects of Eye Movements. Documenta Ophthalmologica Proceedings Series, vol 34. Springer, Dordrecht. https://doi.org/10.1007/978-94-009-8000-6_32
Download citation
DOI: https://doi.org/10.1007/978-94-009-8000-6_32
Publisher Name: Springer, Dordrecht
Print ISBN: 978-94-009-8002-0
Online ISBN: 978-94-009-8000-6
eBook Packages: Springer Book Archive