Time Course of Oculomotor Inhibition Revealed by Saccade Trajectory Modulation

Selecting a stimulus as the target for a goal-directed movement involves inhibiting other competing possible responses. Both target and distractor stimuli activate populations of neurons in topographic oculomotor maps such as the superior colliculus. Local inhibitory interconnections between these populations ensure only one saccade target is selected. Suppressing saccades to distractors may additionally involve inhibiting corresponding map regions to bias the local competition. Behavioral evidence of these inhibitory processes comes from the effects of distractors on oculomotor and manual trajectories. Individual saccades may initially deviate either toward or away from a distractor, but the source of this variability has not been investigated. Here we investigate the relation between distractor-related deviation of trajectory and saccade latency. Targets were presented with, or without, distractors, and the deviation of saccade trajectories arising from the presence of distractors was measured. A fixation gap paradigm was used to manipulate latency independently of the influence of competing distractors. Shorter-latency saccades deviated toward distractors and longer-latency saccades deviated away from distractors. The transition between deviation toward or away from distractors occurred at a saccade latency of around 200 ms. This shows that the time course of the inhibitory process involved in distractor related suppression is relatively slow.

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Early and Late Modulation of Saccade Deviations by Target Distractor Similarity

Journal of Neurophysiology ◽

10.1152/jn.00068.2009 ◽

2009 ◽

Vol 102 (3) ◽

pp. 1451-1458 ◽

Cited By ~ 47

Author(s):

Manon Mulckhuyse ◽

Stefan Van der Stigchel ◽

Jan Theeuwes

Keyword(s):

Time Course ◽

Relevant Information ◽

Dependent Measure ◽

Saccade Latency ◽

Oculomotor Control ◽

Opposite Pattern ◽

Selection Processes ◽

Time Courses ◽

Saccade Trajectory ◽

Rule Out

In this study, we investigated the time course of oculomotor competition between bottom-up and top-down selection processes using saccade trajectory deviations as a dependent measure. We used a paradigm in which we manipulated saccade latency by offsetting the fixation point at different time points relative to target onset. In experiment 1, observers made a saccade to a filled colored circle while another irrelevant distractor circle was presented. The distractor was either similar (i.e., identical) or dissimilar to the target. Results showed that the strength of saccade deviation was modulated by target distractor similarity for short saccade latencies. To rule out the possibility that the similar distractor affected the saccade trajectory merely because it was identical to the target, the distractor in experiment 2 was a square shape of which only the color was similar or dissimilar to the target. The results showed that deviations for both short and long latencies were modulated by target distractor similarity. When saccade latencies were short, we found less saccade deviation away from a similar than from a dissimilar distractor. When saccade latencies were long, the opposite pattern was found: more saccade deviation away from a similar than from a dissimilar distractor. In contrast to previous findings, our study shows that task-relevant information can already influence the early processes of oculomotor control. We conclude that competition between saccadic goals is subject to two different processes with different time courses: one fast activating process signaling the saliency and task relevance of a location and one slower inhibitory process suppressing that location.

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Effect of Remote Distractors on Saccade Programming: Evidence for an Extended Fixation Zone

Journal of Neurophysiology ◽

10.1152/jn.1997.78.2.1108 ◽

1997 ◽

Vol 78 (2) ◽

pp. 1108-1119 ◽

Cited By ~ 237

Author(s):

Robin Walker ◽

Heiner Deubel ◽

Werner X. Schneider ◽

John M. Findlay

Keyword(s):

Visual Field ◽

Quantitative Relationship ◽

Saccade Latency ◽

Saccade Target ◽

Inhibitory Processes ◽

Principal Axes ◽

Saccade Programming ◽

Series Of Experiments ◽

Rostral Region ◽

The Relationship

Walker, Robin, Heiner Deubel, Werner X. Schneider, and John M. Findlay. Effect of remote distractors on saccade programming: evidence for an extended fixation zone. J. Neurophysiol. 78: 1108–1119, 1997. In a series of experiments, we examined the increase in saccade latency that is observed consistently when distractor stimuli are presented simultaneously with the saccade target at various nontarget locations. In the first experiment, targets and distractors were presented on the horizontal axis. We found that saccade latency was increased when distractors appeared at fixation and in the contralateral nontarget hemifield (at eccentricities ≤10°). In contrast, latency was unaffected by distractors presented along the ipsilateral target axis, but amplitude was increased as saccades tended to land at intermediate locations between the two stimuli (global effect). The effect of presenting distractors at various two-dimensional locations in both the target and nontarget hemifields then was examined, and the maximum latency increase again was observed when distractors appeared at fixation. Distractors presented on any of the eight principal axes in either hemifield, other than on the horizontal target axis, also increased latency. The relationship between the effects of distractors on latency and amplitude was reciprocal. Within ∼20° of the target axis itself, distractors affected saccade amplitude but not latency. In contrast, distractors presented outside this “window” increased saccade latency without affecting amplitude. A systematic quantitative relationship was revealed between the increase in latency and the ratio between target and distractor eccentricities. The latency increase was largest with small values of the ratio and reached a peak with distractors at the fixation location. The finding that the increase observed for more eccentric distractor locations fitted the same function as that at fixation shows that inhibitory effects operate over large areas of the visual field. The increase in latency under distractor conditions is interpreted in light of recent neurophysiological findings of inhibitory processes operating in the rostral region of the superior colliculus. Our results suggest that these inhibitory processes are not restricted to the central foveal region alone but operate over wider regions of the visual field.

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Engaging regularly with fiction influences connectivity in cortical areas for language and mentalizing

10.31234/osf.io/e7bqj ◽

2017 ◽

Author(s):

Roel M. Willems ◽

Franziska Hartung

Keyword(s):

Functional Connectivity ◽

Time Course ◽

Language Skills ◽

Brain Regions ◽

Brain Areas ◽

Daily Lives ◽

Cortical Areas ◽

Social Abilities ◽

Behavioral Evidence ◽

Amount Of Reading

Behavioral evidence suggests that engaging with fiction is positively correlated with social abilities. The rationale behind this link is that engaging with fictional narratives offers a ‘training modus’ for mentalizing and empathizing. We investigated the influence of the amount of reading that participants report doing in their daily lives, on connections between brain areas while they listened to literary narratives. Participants (N=57) listened to two literary narratives while brain activation was measured with fMRI. We computed time-course correlations between brain regions, and compared the correlation values from listening to narratives to listening to reversed speech. The between-region correlations were then related to the amount of fiction that participants read in their daily lives. Our results show that amount of fiction reading is related to functional connectivity in areas known to be involved in language and mentalizing. This suggests that reading fiction influences social cognition as well as language skills.

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Integration of allocentric and egocentric visual information in a convolutional / multilayer perceptron network model of goal-directed gaze shifts

10.1101/2021.12.15.472867 ◽

2021 ◽

Author(s):

Parisa Abedi Khoozani ◽

Vishal Bharmauria ◽

Adrian Schuetz ◽

Richard P. Wildes ◽

John Douglas Crawford

Keyword(s):

Multilayer Perceptron ◽

Visual Information ◽

General Framework ◽

Movement Control ◽

Saccade Target ◽

Directed Movement ◽

Visuomotor Transformations ◽

Multilayer Perceptron Network ◽

Mlp Model ◽

Gaze Position

Allocentric (landmark-centered) and egocentric (eye-centered) visual codes are fundamental for spatial cognition, navigation, and goal-directed movement. Neuroimaging and neurophysiology suggest these codes are segregated initially, but then reintegrated in frontal cortex for movement control. We created and validated a theoretical framework for this process using physiologically constrained inputs and outputs. To implement a general framework, we integrated a Convolutional Neural Network (CNN) of the visual system with a Multilayer Perceptron (MLP) model of the sensorimotor transformation. The network was trained on a task where a landmark shifted relative to the saccade target. These visual parameters were input to the CNN, the CNN output and initial gaze position to the MLP, and a decoder transformed MLP output into saccade vectors. Decoded saccade output replicated idealized training sets with various allocentric weightings, and actual monkey data where the landmark shift had a partial influence (R2 = 0.8). Furthermore, MLP output units accurately simulated prefrontal response field shifts recorded from monkeys during the same paradigm. In summary, our model replicated both the general properties of the visuomotor transformations for gaze and specific experimental results obtained during allocentric-egocentric integration, suggesting it can provide a general framework for understanding these and other complex visuomotor behaviors.

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Homographs Processing in Sentence Context: Inhibitory Processes and Time Course

PsycEXTRA Dataset ◽

10.1037/e502412013-583 ◽

2012 ◽

Author(s):

Maria Cruz Martin ◽

Pedro Macizo ◽

Maria Teresa Bajo

Keyword(s):

Time Course ◽

Sentence Context ◽

Inhibitory Processes

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Homographs processing in sentence context: Inhibitory processes and their time course

PsycEXTRA Dataset ◽

10.1037/e512592013-212 ◽

2011 ◽

Author(s):

M. C. Martin ◽

P. Macizo ◽

M. T. Bajo

Keyword(s):

Time Course ◽

Sentence Context ◽

Inhibitory Processes

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Stimulus-salience and the time-course of saccade trajectory deviations

Journal of Vision ◽

10.1167/12.8.16 ◽

2012 ◽

Vol 12 (8) ◽

pp. 16-16 ◽

Cited By ~ 15

Author(s):

W. van Zoest ◽

M. Donk ◽

S. Van der Stigchel

Keyword(s):

Time Course ◽

Stimulus Salience ◽

Saccade Trajectory

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Saccadic eye movements in dual tasking: No impairment of spatial planning, but delayed execution of saccades

Quarterly Journal of Experimental Psychology ◽

10.1177/1747021820960693 ◽

2020 ◽

pp. 174702182096069

Author(s):

Christina B Reimer ◽

Luke Tudge ◽

Torsten Schubert

Keyword(s):

Spatial Planning ◽

Response Selection ◽

Selection Process ◽

Saccade Latency ◽

Button Press ◽

Manual Response ◽

Manual Task ◽

Manual Responses ◽

Saccade Task ◽

Saccade Trajectory

In the target–distractor saccade task, a target and an irrelevant distractor are simultaneously presented and the task itself consists of a target-directed saccade. Findings usually show that as saccade latency increases, saccade trajectory deviation towards the distractor decreases. We presented this saccade task in two dual-task experiments to address the open question of whether performance of an auditory–manual task simply delays the temporal execution of a saccade, or whether it also interferes with the spatial planning of the saccade trajectory. We measured saccade latency, as a measure of a delay in execution, and saccade trajectory deviation, as a measure of the spatial planning. In Experiment 1, the auditory–manual task was a two-choice reaction time (two-CRT) task, and in Experiment 2, it was a go-no-go task. Performing the two tasks in close temporal succession shortly delayed the temporal execution of the saccade, but did not influence the spatial planning of the saccade trajectory. This result pattern was more pronounced when the auditory–manual task required the selection and execution of one of two possible manual responses (Experiment 1), less pronounced when the auditory–manual task required the decision to execute a button press (go condition, Experiment 2), and absent when the auditory–manual task required the decision to inhibit a button press (no-go condition, Experiment 2). Taken together, the manual response rather than the response selection process of the auditory–manual task led to a delay of saccade execution, but not to an impairment of the spatial planning of the saccade trajectory.

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