scholarly journals Absence of an extraretinal signal associated with ocular drift affects saccade accuracy

2011 ◽  
Vol 11 (11) ◽  
pp. 557-557
Author(s):  
M. Poletti ◽  
M. Rucci
Keyword(s):  
Extraretinal Signal

Visual responses of pulvinar and collicular neurons during eye movements of awake, trained macaques

1991 ◽  
Vol 66 (2) ◽  
pp. 485-496 ◽  
Author(s):  
D. L. Robinson ◽  
J. W. McClurkin ◽  
C. Kertzman ◽  
S. E. Petersen
Keyword(s):  
Eye Movements ◽  
Superior Colliculus ◽  
Visual Stimulation ◽  
Receptive Fields ◽  
Visual Responses ◽  
Stimulus Motion ◽  
Stimulus Movement ◽  
Pursuit Eye Movements ◽  
Extraretinal Signal ◽  
Wide Range

1. We recorded from single neurons in awake, trained rhesus monkeys in a lighted environment and compared responses to stimulus movement during periods of fixation with those to motion caused by saccadic or pursuit eye movements. Neurons in the inferior pulvinar (PI), lateral pulvinar (PL), and superior colliculus were tested. 2. Cells in PI and PL respond to stimulus movement over a wide range of speeds. Some of these cells do not respond to comparable stimulus motion, or discharge only weakly, when it is generated by saccadic or pursuit eye movements. Other neurons respond equivalently to both types of motion. Cells in the superficial layers of the superior colliculus have similar properties to those in PI and PL. 3. When tested in the dark to reduce visual stimulation from the background, cells in PI and PL still do not respond to motion generated by eye movements. Some of these cells have a suppression of activity after saccadic eye movements made in total darkness. These data suggest that an extraretinal signal suppresses responses to visual stimuli during eye movements. 4. The suppression of responses to stimuli during eye movements is not an absolute effect. Images brighter than 2.0 log units above background illumination evoke responses from cells in PI and PL. The suppression appears stronger in the superior colliculus than in PI and PL. 5. These experiments demonstrate that many cells in PI and PL have a suppression of their responses to stimuli that cross their receptive fields during eye movements. These cells are probably suppressed by an extraretinal signal. Comparable effects are present in the superficial layers of the superior colliculus. These properties in PI and PL may reflect the function of the ascending tectopulvinar system.

Use of an extraretinal signal by monkey superior colliculus neurons to distinguish real from self-induced stimulus movement

1976 ◽  
Vol 39 (4) ◽  
pp. 852-870 ◽  
Author(s):  
D. L. Robinson ◽  
R. H. Wurtz
Keyword(s):  
Eye Movements ◽  
Superior Colliculus ◽  
Eye Movement ◽  
Visual Stimulation ◽  
Receptive Fields ◽  
Saccadic Eye Movement ◽  
Background Illumination ◽  
Stimulus Movement ◽  
Stationary Stimulus ◽  
Extraretinal Signal

1. In order to see whether cells in the superficial layers of the monkey superior colliculus can differentiate between real stimulus movement and self-induced stimulus movement we compared the discharge of these cells to stimulus movement in front of the stationary eye with stimulus movement generated by eye movements across a stationary stimulus. 2. Most of the cells recorded (65% of 231 cells) responded to stimulus velocities in front of the stationary eye as fast as those occurring during the peak velocity of a saccadic eye movement. Those cells that do respond usually have weak inhibitory regions and tend to have receptive fields further from fovea. 3. Move (61% of 105 cells) of the cells that did respond to rapid stimulus movement did not respond when an eye movement swept the receptive field over a stationary stimulus. 4. About half of these cells differentiated between these stimulus conditions when we used stimuli at least 1 log unit above background illumination; the remaining cells differentiated for stimuli 2 and 3 log units above background. Many cells differentiated between the two stimulus conditions over a wide range of directions of movement and the effect appears with about equal frequency in receptive fields at all distances from the fovea. 5. The differentiation is present for most cells even when the background illumination is reduced, indicating that visual factors are not the cause of the effect on these cells but may modify the response of other cells. 6. The suppression of background activity accompanying eye movements in the light is present following eye movements made in total darkness; the suppression, therefore, must result from an extraretinal signal. 4. The failure of these cells to respond to visual stimulation during eye movements is due to the same extraretinal signal that produces the suppression since a) the cells that show this suppression tend to be those that fail to respond to stimuli during eye movements, b) the time course of the suppression matches the time at which the effects of visual stimulation during an eye movement would reach the colliculus, and c) the cells which differentiate also show a decreased responsiveness to visual stimulation during the time of background suppression. While this extraretinal signal has the characteristics one would expect of a corollary discharge, proprioception as a source of the signal cannot be excluded. 8. Cells which differentiate between the two stimulus conditions usually also show an enhanced response to a visual stimulus in their receptive field when it is to be the target for a saccadic eye movement. These cells in the superior colliculus receive an extraretinal input which permits them to differentiate betweent real stimulus movements and stimulus movements resulting from the monkey's own eye movements. This differentiation would provide an uncontaminated visual movement signal and facilitate the detection of real movement in the environment...

scholarly journals The extraretinal signal for the visual perception of direction

1972 ◽  
Vol 11 (4) ◽  
pp. 287-290 ◽  
Author(s):  
Alexander A. Skavenski ◽  
Genevieve Haddad ◽  
Robert M. Steinman
Keyword(s):  
Visual Perception ◽  
Extraretinal Signal

scholarly journals Extraretinal signal metrics in multiple-saccade sequences

2010 ◽  
Vol 10 (14) ◽  
pp. 7-7 ◽  
Author(s):  
T. Collins
Keyword(s):  
Extraretinal Signal

Modulation of Gaze-Evoked Blinks Depends Primarily on Extraretinal Factors

2005 ◽  
Vol 93 (1) ◽  
pp. 627-632 ◽  
Author(s):  
Shawn S. Williamson ◽  
Ari Z. Zivotofsky ◽  
Michele A. Basso
Keyword(s):  
Visual Stimulus ◽  
Visual Information ◽  
Human Subjects ◽  
Saccadic Eye Movements ◽  
Spatial Location ◽  
Visually Guided ◽  
Gaze Shift ◽  
The Gaze ◽  
Extraretinal Signal ◽  
Common Drive

Gaze-evoked blinks are contractions of the orbicularis oculi (OO)—the lid closing muscle—occurring during rapid movements of the head and eyes and result from a common drive to the gaze and blink motor systems. However, blinks occurring during shifts of gaze are often suppressed when the gaze shift is made to an important visual stimulus, suggesting that the visual system can modulate the occurrence of these blinks. In head-stabilized, human subjects, we tested the hypothesis that the presence of a visual stimulus was sufficient, but not necessary, to modulate OO EMG (OOemg) activity during saccadic eye movements. Rapid, reorienting movements of the eyes (saccades) were made to visual targets that remained illuminated (visually guided trials) or were briefly flashed (memory-guided trials) at different amplitudes along the horizontal meridian. We measured OOemg activity and found that the magnitude and probability of OOemg activity occurrence was reduced when a saccade was made to the memory of the spatial location as well as to the actual visual stimulus. The reduced OOemg activity occurred only when the location of the target was previously cued. OOemg activity occurred reliably with spontaneous saccades that were made to locations with no explicit visual stimulus, generally, back to the fixation location. Thus the modulation of gaze-evoked OOemg activity does not depend on the presence of visual information per se, but rather, results from an extraretinal signal.

Activity Linked to Externally Cued Saccades in Single Units Recorded From Hippocampal, Parahippocampal, and Inferotemporal Areas of Macaques

1997 ◽  
Vol 78 (4) ◽  
pp. 2156-2163 ◽  
Author(s):  
Stanislaw Sobotka ◽  
Anna Nowicka ◽  
James L. Ringo
Keyword(s):  
Eye Movements ◽  
Visual Information ◽  
Visual Memory ◽  
Hippocampal Formation ◽  
Saccadic Eye Movements ◽  
Brain Structures ◽  
Single Units ◽  
Parahippocampal Gyrus ◽  
Visual Response ◽  
Extraretinal Signal

Sobotka, Stanislaw, Anna Nowicka, and James L. Ringo. Activity linked to externally cued saccades in single units recorded from hippocampal, parahippocampal, and inferotemporal areas of macaques. J. Neurophysiol. 78: 2156–2163, 1997. We studied whether target-directed, externally commanded saccadic eye movements (saccades) induced activity in single units in inferotemporal cortex, the hippocampal formation, and parahippocampal gyrus. The monkeys first were required to fix their gaze on a small cross presented to the left or right of center on the monitor screen. The cross was extinguished, and a random 600–1,000 ms thereafter, a small dot was presented for 200 ms. The dot was located either 10° above, below, right, or left of the position on which the fixation cross had been. The monkey made a saccadic eye movement to this dot (in darkness). The neuronal activity around this goal-directed saccade was analyzed. In addition, control conditions were imposed systematically in which similar dots were presented, but the monkey's task was to withhold the saccade. We recorded 290 units from two monkeys. From this group, 134 met two criteria, they did not show visual response in control trials and they had spike rates >2 Hz. These were analyzed further; 53% (71/134) showed modulation related to the target directed saccade, and 29% (39/134) showed saccadic modulation during spontaneous eye movements. These two groups were correlated only weakly. Of the units with significant saccadic modulation, 17% (12/71) showed significant directional selectivity, and 13% (9/71) showed significant position selectivity ( P < 0.01). At a lower criterion ( P < 0.05), almost one-half (33/71) showed one or the other spatial selectivity. Primates use saccades to acquire visual information. The appearance of strong saccadic modulation in brain structures previously characterized as mnemonic suggests the possibility that the mnemonic circuitry uses an extraretinal signal linked to saccades to control visual memory processes, e.g., synchronizing mnemonic processes to the pulsatile visual data inflow.

A Computational Model of the Eye Movement Effects on Motion Perception

Perception ◽  
1996 ◽  
Vol 25 (1_suppl) ◽  
pp. 166-166
Author(s):  
K A Turano ◽  
S M Heidenreich
Keyword(s):  
Computational Model ◽  
Eye Movement ◽  
Motion Perception ◽  
Opposite Direction ◽  
Retinal Image ◽  
Vision Research ◽  
Opposite Sign ◽  
Motion Information ◽  
Extraretinal Signal ◽  
Moving Stimulus

Accurate speed and direction matches can be made between a moving stimulus viewed with a stationary eye and a moving stimulus viewed with an eye moving in the opposite direction to the stimulus. However, when the eye moves in the same direction as the distal stimulus, at a slower speed, subjects match the retinal-image motions of the stimuli rather than their distal motions (Heidenreich and Turano, 1995 Investigative Ophthalmology and Visual Science36 1675). Furthermore, it is only under this latter condition (and when the eye is stationary) that subjects can precisely discriminate distal stimulus speeds (Turano and Heidenreich Vision Research in press). We present a computational model that can account for the results of all three findings. The model assumes that the extraretinal signal mirrors the eye movement. Motion information from the retinal and extraretinal sources is combined in a subtractive manner when the two signals have opposite sign. When the two signals have the same sign, they do not combine, and motion judgments are based solely on information from the retinal source.

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