 |
Previous Article | Next Article 
Volume 17, Number 19,
Issue of October 1, 1997
pp. 7490-7502
Copyright ©1997 Society for Neuroscience
Vector Averaging for Smooth Pursuit Eye Movements Initiated by
Two Moving Targets in Monkeys
Received May 6, 1997; revised June 20, 1997; accepted July 14, 1997.
Stephen G. Lisberger1 and
Vincent P. Ferrera2
1 Howard Hughes Medical Institute, Department of
Physiology, W. M. Keck Foundation Center for Integrative
Neuroscience, and Sloan Center for Theoretical Neurobiology, University
of California, San Francisco, California 94143, and
2 Department of Psychiatry and Center for Neurobiology and
Behavior, Columbia University, New York, New York 10032
The visual input for pursuit eye movements is represented in the
cerebral cortex as the distributed activity of neurons that are tuned
for both the direction and speed of target motion. To probe how the
motor system uses this distributed code to compute a command for smooth
eye movements, we have recorded the initiation of pursuit for 150 msec
presentations of two spots moving at different speeds and/or in
different directions. With equal probability, one of the two spots
continued to move at the same speed and in the same direction and
became the tracking target, whereas the other disappeared and served as
a distractor. We measured eye acceleration in the interval from 110 to
206 msec after the onset of spot motion, within both the open-loop
interval for pursuit and the interval during which eye motion was
affected by the two spots. Our results demonstrate that weighted vector
averaging is used to combine the responses to two moving spots. We
found only a minute number of responses that were consistent with
either vector summation or winner-take-all computations. In addition, our data show that it is difficult for the monkey to defeat vector averaging without extended training on the use of an explicit cue about
which spot will become the target. We argue that our experiment reveals
the computations done by the pursuit system in the absence of
attentional bias and that vector averaging is normally used to read the
distributed code of image motion when there is only one target.
Key words:
visual motion processing;
eye movements;
smooth pursuit;
sensorimotor transformation;
vector averaging;
winner-take-all
This article has been cited by other articles:

|
 |

|
 |
 
G. R. Case and V. P. Ferrera
Coordination of Smooth Pursuit and Saccade Target Selection in Monkeys
J Neurophysiol,
October 1, 2007;
98(4):
2206 - 2214.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
M. Spering and K. R. Gegenfurtner
Contrast and Assimilation in Motion Perception and Smooth Pursuit Eye Movements
J Neurophysiol,
September 1, 2007;
98(3):
1355 - 1363.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
B. S. Webb, T. Ledgeway, and P. V. McGraw
Cortical pooling algorithms for judging global motion direction
PNAS,
February 27, 2007;
104(9):
3532 - 3537.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
S. Garbutt and S. G. Lisberger
Directional Cuing of Target Choice in Human Smooth Pursuit Eye Movements
J. Neurosci.,
November 29, 2006;
26(48):
12479 - 12486.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
R. T. Born, C. C. Pack, C. R. Ponce, and S. Yi
Temporal Evolution of 2-Dimensional Direction Signals Used to Guide Eye Movements
J Neurophysiol,
January 1, 2006;
95(1):
284 - 300.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
E. S. Frechette, A. Sher, M. I. Grivich, D. Petrusca, A. M. Litke, and E. J. Chichilnisky
Fidelity of the Ensemble Code for Visual Motion in Primate Retina
J Neurophysiol,
July 1, 2005;
94(1):
119 - 135.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
S. Marti, C. J. Bockisch, and D. Straumann
Prolonged Asymmetric Smooth-Pursuit Stimulation Leads to Downbeat Nystagmus in Healthy Human Subjects
Invest. Ophthalmol. Vis. Sci.,
January 1, 2005;
46(1):
143 - 149.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
D. Liston and R. J. Krauzlis
Shared Response Preparation for Pursuit and Saccadic Eye Movements
J. Neurosci.,
December 10, 2003;
23(36):
11305 - 11314.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
M. J. Nichols and W. T. Newsome
Middle Temporal Visual Area Microstimulation Influences Veridical Judgments of Motion Direction
J. Neurosci.,
November 1, 2002;
22(21):
9530 - 9540.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
G. S. Masson and E. Castet
Parallel Motion Processing for the Initiation of Short-Latency Ocular Following in Humans
J. Neurosci.,
June 15, 2002;
22(12):
5149 - 5163.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
M. Tanaka and S. G. Lisberger
Role of Arcuate Frontal Cortex of Monkeys in Smooth Pursuit Eye Movements. I. Basic Response Properties to Retinal Image Motion and Position
J Neurophysiol,
June 1, 2002;
87(6):
2684 - 2699.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
M. Tanaka and S. G. Lisberger
Role of Arcuate Frontal Cortex of Monkeys in Smooth Pursuit Eye Movements. II. Relation to Vector Averaging Pursuit
J Neurophysiol,
June 1, 2002;
87(6):
2700 - 2714.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
J. L. Gardner and S. G. Lisberger
Linked Target Selection for Saccadic and Smooth Pursuit Eye Movements
J. Neurosci.,
March 15, 2001;
21(6):
2075 - 2084.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
V. P. Ferrera
Task-Dependent Modulation of the Sensorimotor Transformation for Smooth Pursuit Eye Movements
J Neurophysiol,
December 1, 2000;
84(6):
2725 - 2738.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
M. Kahlon and S. G. Lisberger
Vector Averaging Occurs Downstream from Learning in Smooth Pursuit Eye Movements of Monkeys
J. Neurosci.,
October 15, 1999;
19(20):
9039 - 9053.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
G. H. Recanzone and R. H. Wurtz
Shift in Smooth Pursuit Initiation and MT and MST Neuronal Activity Under Different Stimulus Conditions
J Neurophysiol,
October 1, 1999;
82(4):
1710 - 1727.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
K. C. Engel, J. H. Anderson, and J. F. Soechting
Oculomotor Tracking in Two Dimensions
J Neurophysiol,
April 1, 1999;
81(4):
1597 - 1602.
[Abstract]
[Full Text]
[PDF]
|
 |
|
|