Direction of an initial saccade depends on radiological expertise

Multiple Saccades Are More Automatic Than Single Saccades

Journal of Neurophysiology ◽

10.1152/jn.01339.2006 ◽

2007 ◽

Vol 97 (4) ◽

pp. 3148-3151 ◽

Cited By ~ 14

Author(s):

Paul van Donkelaar ◽

Sandy Saavedra ◽

Marjorie Woollacott

Keyword(s):

Cerebral Cortex ◽

Age Groups ◽

Age Group ◽

Control Task ◽

Initial Saccade ◽

Fixation Control

In this paper, we demonstrate that when a peripheral object is foveated by a sequence of multiple saccades, the initial saccade in the sequence is initiated markedly faster than a single accurate saccade to the same object. We suggest that multiple saccades represent a more automatic form of oculomotor planning that may be the result of a reduced influence from the cerebral cortex. To test this, we compared single and multiple saccade characteristics across development. We find that in contrast to the reduction in the latency of single saccades that is observed across development, the latency of initial saccades in multiple saccade sequences is remarkably stable across all age groups. Moreover, the longer the latency of this initial saccade, the more accurate it is, suggesting that there is a relation between the degree of procrastination and the accuracy of the response. Finally, the frequency with which multiple saccades occurred within each age group was positively correlated with the tendency to generate erroneous saccades during a fixation control task. Taken together, the present data suggest that multiple saccades are generated in a more automatic manner than single saccades.

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Search is enhanced with visual abstinence: Delaying initial saccade latency in familiar scenes improves search guidance

Journal of Vision ◽

10.1167/8.6.872 ◽

2010 ◽

Vol 8 (6) ◽

pp. 872-872

Author(s):

B. Hidalgo-Sotelo ◽

A. Oliva

Keyword(s):

Saccade Latency ◽

Initial Saccade ◽

Search Guidance

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Superior Colliculus Activity Related to Concurrent Processing of Saccade Goals in a Visual Search Task

Journal of Neurophysiology ◽

10.1152/jn.00501.2001 ◽

2002 ◽

Vol 87 (4) ◽

pp. 1805-1815 ◽

Cited By ~ 102

Author(s):

Robert M. McPeek ◽

Edward L. Keller

Keyword(s):

Superior Colliculus ◽

Rhesus Monkeys ◽

Search Task ◽

Visual Search Task ◽

Saccadic System ◽

Concurrent Processing ◽

Initial Saccade ◽

Preparatory Activity ◽

Winner Take All ◽

Initial Movement

Saccades are typically separated by inter-saccadic fixation intervals (ISFIs) of ≥125 ms. During this time, the saccadic system selects a goal and completes the preparatory processes required prior to executing the subsequent movement. However, in tasks in which competing stimuli are presented, two sequentially executed movements to different goals can be separated by much shorter ISFIs. This suggests that the saccadic system is capable of completing many of the preparatory requirements for a second saccade concurrently with the execution of an initial movement. We recorded single neurons in the superior colliculus (SC) during rapid saccade sequences made by rhesus monkeys performing a search task. We found that during the execution of an initial saccade, activity related to the goal of a quickly following second saccade can be simultaneously maintained in the SC motor map. This activity appears to signal the selection or increased salience of the second saccade goal even before the initial saccade has ended. For movements separated by normal ISFIs (≥125 ms), we did not observe activity related to concurrent processing, presumably because for these longer ISFI responses, the goal of the second saccade is not selected until after the end of the first saccade. These results indicate that, at the time of an initial saccade, the SC does not necessarily act as a strict winner-take-all network. Rather it appears that the salience of a second visual goal can be simultaneously maintained in the SC. This provides evidence that selection or preparatory activity related to the goal of a second saccade can overlap temporally with activity related to an initial saccade and indicates that such concurrent processing is present even in a structure which is fairly close to the motor output.

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Correction of Saccade-Induced Midline Errors in Responses to Pure Disparity Vergence Stimuli.

Journal of Eye Movement Research ◽

10.16910/jemr.2.5.1 ◽

2009 ◽

Vol 2 (5) ◽

Author(s):

John L. Semmlow ◽

Yung-Fu Chen ◽

Bérangère Granger-Donnetti ◽

Tara L. Alvarez

Keyword(s):

Eye Movements ◽

Physiological Process ◽

Compensatory Mechanism ◽

Fixation Disparity ◽

Compensatory Mechanisms ◽

Dominant Mechanism ◽

Initial Saccade ◽

Corrective Saccades

Purely symmetrical vergence stimuli aligned along the midline (cyclopean axis) require only a pure vergence response. Yet, in most responses saccades are observed and these saccades must either produce an error in the desired midline response or correct an error produced by asymmetry in the vergence response. A previous study (Semmlow, et al. 2008) has shown that the first saccade to appear in a response to a pure vergence stimulus usually increased the deviation from the midline, although all subjects (N = 12) had some responses where the initial saccade corrected a vergence induced midline error. This study focuses on those responses where the initial saccade produces an increased midline deviation and the resultant compensation that ultimately brings the eyes to the correct binocular position. This correction is accomplished by a higher level compensatory mechanism that uses offsetting asymmetrical vergence and/or corrective saccades. While responses consist of a mixture of the two compensatory mechanisms, the dominant mechanism is subject-dependent. Since fixation errors are quite small (minutes of arc), some feedback controlled physiological process involving smooth eye movements, and possibly saccades, must move the eyes to reduce binocular error to fixation disparity levels.

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Prefrontal Neuronal Activity Encodes Spatial Target Representations Sequentially Updated After Nonspatial Target-Shift Cues

Journal of Neurophysiology ◽

10.1152/jn.00306.2003 ◽

2004 ◽

Vol 91 (3) ◽

pp. 1367-1380 ◽

Cited By ~ 23

Author(s):

Tetsuya Fukushima ◽

Isao Hasegawa ◽

Yasushi Miyashita

Keyword(s):

Neuronal Activity ◽

Target Location ◽

Spatial Working Memory ◽

Target Position ◽

Saccade Target ◽

Visual Response ◽

Initial Saccade ◽

Preparatory Set ◽

Dominant Activity ◽

Selective Activity

We examined prefrontal neuronal activity while monkeys performed a sequential target-shift task, in which, after a positional cue indicated the initial saccade target among 8 peripheral positions, the monkeys were required to internally shift the target by one position on every flash of a target-shift cue. The target-shift cue appeared in the center 0 to 3 times within a single trial and was always the same in shape, size, and color. We found selective neuronal activity related to the target position: when the target-shift cue implied the target shift to particular peripheral positions, neurons exhibited early-dominant and late-dominant activity during the following delay period. The early-dominant target-selective activity emerged early in the delay just after the presentation of the target-shift cue, whereas the late-dominant activity gradually built up toward the end of the delay. Because the target-shift cue was not related to any specific target location, the early-dominant target-selective activity could not be a mere visual response to the target-shift cue. We suggest that the early-dominant activity reflects the transitory representation for the saccade target that was triggered by the nonspatial target-shift cue, whereas the late-dominant activity reflects the target representation in the spatial working memory or the preparatory set for the possible impending saccade, being repeatedly updated during sequential target shifts.

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Velocity profile of smooth pursuit eye movements in humans: pursuit velocity increase linked with the initial saccade occurrence

Neuroscience Research ◽

10.1016/s0168-0102(98)00038-8 ◽

1998 ◽

Vol 31 (3) ◽

pp. 201-209 ◽

Cited By ~ 1

Author(s):

Tadashi Ogawa ◽

Masahiko Fujita

Keyword(s):

Eye Movements ◽

Velocity Profile ◽

Smooth Pursuit ◽

Smooth Pursuit Eye Movements ◽

Velocity Increase ◽

Pursuit Eye Movements ◽

Initial Saccade ◽

Pursuit Velocity

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The Lifetime of Salience Extends Beyond the Initial Saccade

Perception ◽

10.1177/0301006617735726 ◽

2017 ◽

Vol 47 (2) ◽

pp. 125-142 ◽

Cited By ~ 2

Author(s):

Jelmer P. De Vries ◽

Stefan Van der Stigchel ◽

Ignace T. C. Hooge ◽

Frans A. J. Verstraten

Keyword(s):

Short Latency ◽

Orientation Contrast ◽

Initial Saccade ◽

Single Feature

Several models of selection in search predict that saccades are biased toward conspicuous objects (also referred to as salient objects). Indeed, it has been demonstrated that initial saccades are biased toward the most conspicuous candidate. However, in a recent study, no such bias was found for the second saccade, and it was concluded that the attraction of conspicuous elements is limited to only short-latency initial saccades. This conclusion is based on only a single feature manipulation (orientation contrast) and conflicts with the prediction of influential salience models. Here, we investigate whether this result can be generalized beyond the domain of orientation. In displays containing three luminance annuli (Experiment 1), we find a considerable bias toward the most conspicuous candidate for the second saccade. In Experiment 1, the target could not be discriminated peripherally. When we made the target peripherally discriminable, the second saccade was no longer biased toward the more conspicuous candidate (Experiment 2). Thus, conspicuity plays a role in saccadic selection beyond the initial saccade. Whether second saccades are biased toward conspicuous objects appears to depend on the type of feature contrast underlying the conspicuity and the peripheral discriminability of target properties.

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Eye movements in real-world scene photographs: General characteristics and effects of viewing task

10.31234/osf.io/e74kb ◽

2019 ◽

Author(s):

Deborah Cronin ◽

Elizabeth Hall ◽

Jessica E. Goold ◽

Taylor Hayes ◽

John M. Henderson

Keyword(s):

Eye Movement ◽

Real World ◽

Fixation Duration ◽

Saccade Latency ◽

Movement Behavior ◽

Aesthetic Judgement ◽

Initial Saccade ◽

Large N ◽

The Mean ◽

Future Work

The present study examines eye movement behavior in real-world scenes with a large (N=100) sample. We report baseline measures of eye movement behavior in our sample, including mean fixation duration, saccade amplitude, and initial saccade latency. We also characterize how eye movement behaviors change over the course of a 12 second trial. These baseline measures will be of use to future work studying eye movement behavior in scenes in a variety of literatures. We also examine effects of viewing task on when and where the eyes move in real-world scenes: participants engaged in a memorization and an aesthetic judgement task while viewing 100 scenes. While we find no difference at the mean-level between the two tasks, temporal- and distribution-level analyses reveal significant task-driven differences in eye movement behavior.

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