Conceptual issues related to the role of the superior colliculus in the control of gaze

Current Opinion in Neurobiology

Volumn 9, Issue 6, 1999, Pages 698-707

  Sparks, David L ^a  

^a BAYLOR COLLEGE OF MEDICINE   (United States)

Author keywords

[No Author keywords available]

Indexed keywords

BINOCULAR CONVERGENCE; EYE MOVEMENT CONTROL; GAZE; NONHUMAN; PRIORITY JOURNAL; REVIEW; SACCADIC EYE MOVEMENT; SUPERIOR COLLICULUS;

EID: 0032763981     PISSN: 09594388     EISSN: None     Source Type: Journal    
DOI: 10.1016/S0959-4388(99)00039-2     Document Type: Review

References (96)

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90. Tate A.K., Malpeli J.G. Effects of focal inactivation of dorsal or ventral layers of the lateral geniculate nucleus on cats' ability to see and fixate small targets. J Neurophysiol. 80:1998;2206-2209. This paper provides evidence that signals conveyed by neurons in layer A of the lateral geniculate nucleus, but not the signals carried by neurons in layer C, are critical for programming accurate saccadic eye movements. Corticotectal pathways are implicated in the deficits observed after layer A inactivation. Inactivation of C layers has little effect on visual responses of corticotectal cells, whereas visually-driven activity of many, but not all, corticotectal cells is dependent on layer A input.
91. Weyand T.G., Gafka A.C. Corticostriatal and corticotectal neurons in area 6 of the cat during fixation and eye movements. Vis Neurosci. 15:1998;141-151.
92. Bozis A., Moschovakis A. Neural network simulations of the primate oculomotor system. III. An one-dimensional, one-directional model of the superior colliculus. Biol Cybern. 79:1998;215-230. A neural network model of the saccadic system specifically designed to be consistent with what is known about the anatomy and physiology of the SC is presented and discussed in this paper. The model accounts for the accuracy of saccades in double step experiments, the effects of focal SC lesions, and the properties of saccades evoked by electrical stimulation of the SC.
93. Krommenhoek K.P., Wiegerinck W.A. A neural network study of precollicular saccadic averaging. Biol Cybern. 78:1998;465-477. The authors present a (somewhat complicated) analysis of what happens in the hidden layers of a neural network model that generates activity in the output layers representing a single motor error when two retinal targets with different intensities are simultaneously presented to the network.
94. Schlag J., Pouget A., Sadeghpour S., Schlag-Rey M. Interactions between natural and electrically evoked saccades. III. Is the nonstationarity the result of an integrator not instantaneously reset? J Neurophysiol. 79:1998;903-910. This paper concludes that the results of previous experiments examining the interactions between natural and electrically evoked saccades do not test the properties of a feedback integrator. However, whether or not the data presented in the paper support this conclusion is questionable (send e-mail to sparks@saccade.neusc.bcm.tmc.edu to obtain a more detailed technical argument).
95. Quaia C., Lefevre P., Optican L.M. Model of the control of saccades by superior colliculus and cerebellum. J Neurophysiol. 82:1999;999-1018. This paper describes a model in which the cerebellum and SC are jointly involved in the initiation and execution of saccades. In this model, collicular neurons initiate saccades by disfacilitating pontine OPNs and provide directional drive to the brainstem circuitry. In terms of saccade amplitude, the SC generates signals that would always produce hypermetric saccades. The model assumes that the cerebellum can modify the directional signal, track the progress of the saccade toward the target (i.e. serve as a resettable displacement integrator) and terminate saccades by turning off collicular signals. The model makes a number of interesting predictions that are testable using available methods.
96. Keller E.L., Edelman J.A. Use of interrupted saccade paradigm to study spatial and temporal dynamics of saccadic burst cells in superior colliculus in monkey. J Neurophysiol. 72:1994;2754-2770.