Target Selection for Reaching and Saccades Share a Similar Behavioral Reference Frame in the Macaque

Hansjörg Scherberger; Melvyn A. Goodale; Richard A. Andersen

doi:10.1152/jn.00883.2002

Target Selection for Reaching and Saccades Share a Similar Behavioral Reference Frame in the Macaque

Journal of Neurophysiology ◽

10.1152/jn.00883.2002 ◽

2003 ◽

Vol 89 (3) ◽

pp. 1456-1466 ◽

Cited By ~ 37

Author(s):

Hansjörg Scherberger ◽

Melvyn A. Goodale ◽

Richard A. Andersen

Keyword(s):

Reference Frame ◽

Target Location ◽

Target Selection ◽

Arm Movements ◽

Quantitative Measure ◽

Arm Movement ◽

Saccade Target ◽

Internal Variables ◽

Coordinate Frame ◽

Selection For

The selection of one of two visual stimuli as a target for a motor action may depend on external as well as internal variables. We examined whether the preference to select a leftward or rightward target depends on the action that is performed (eye or arm movement) and to what extent the choice is influenced by the target location. Two targets were presented at the same distance to the left and right of a fixation position and the stimulus onset asynchrony (SOA) was adjusted until both targets were selected equally often. This balanced SOA time is then a quantitative measure of selection preference. In two macaque monkeys tested, we found the balanced SOA shifted to the left side for left-arm movements and to the right side for right-arm movements. Target selection strongly depended on the horizontal target location. By varying eye, head, and trunk position, we found this dependency embedded in a head-centered behavioral reference frame for saccade targets and, somewhat counter-intuitively, for reach targets as well. Target selection for reach movements was influenced by the eye position, while saccade target selection was unaffected by the arm position. These findings suggest that the neural processes underlying target selection for a reaching movement are to a large extent independent of the coordinate frame ultimately used to make the limb movement, but are instead closely linked to the coordinate frame used to plan a saccade to that target. This similarity may be indicative of a common spatial framework for hand-eye coordination.

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Neurons in the Primate Superior Colliculus Coding for Arm Movements in Gaze-Related Coordinates

Journal of Neurophysiology ◽

10.1152/jn.2000.83.3.1283 ◽

2000 ◽

Vol 83 (3) ◽

pp. 1283-1299 ◽

Cited By ~ 120

Author(s):

Veit Stuphorn ◽

Erhard Bauswein ◽

Klaus-Peter Hoffmann

Keyword(s):

Superior Colliculus ◽

Reference Frame ◽

Target Location ◽

Arm Movements ◽

Target Position ◽

Arm Movement ◽

Mesencephalic Reticular Formation ◽

The Gaze ◽

Motor Error ◽

Deep Layers

In the intermediate and deep layers of the superior colliculus (SC), a well-established oculomotor structure, a substantial population of cells is involved in the control of arm movements. To examine the reference frame of these neurons, we recorded in two rhesus monkeys ( Macaca mulatta) the discharges of 331 neurons in the SC and the underlying mesencephalic reticular formation (MRF) while monkeys reached to the same target location during different gaze orientations. For 65 reach-related cells with sufficient data and for simultaneously recorded electromyograms (EMGs) of 11 arm muscles, we calculated an ANOVA (factors: target position, gaze angle) and a gaze-dependency (GD) index. EMGs and the activity of many (60%) of the reach-related neurons were not influenced by the target representation on the retina or eye position. We refer to these as “gaze-independent” reach neurons. For 40%, however, the GD fell outside the range of the muscle modulation, and the ANOVA showed a significant influence of gaze. These “gaze-related” reach neurons discharge only when the monkey reaches for targets having specific coordinates in relation to the gaze axis, i.e., for targets in a gaze-related “reach movement field” (RMF). Neuronal activity was not modulated by the specific path of the arm movement, the muscle pattern that is necessary for its realization or the arm that was used for the reach. In each SC we found gaze-related neurons with RMFs both in the contralateral and in the ipsilateral hemifield. The topographical organization of the gaze-related reach neurons in the SC could not be matched with the well-known visual and oculomotor maps. Gaze-related neurons were more modulated in their strength of activity with different directions of arm movements than were gaze-independent reach neurons. Gaze-related reach neurons were recorded at a median depth of 2.03 mm below SC surface in the intermediate layers, where they overlap with saccade-related burst neurons (median depth: 1.55 mm). Most of the gaze-independent reach cells were found in a median depth of 4.01 mm below the SC surface in the deep layers and in the underlying MRF. The gaze-related reach neurons operating in a gaze-centered coordinate system could signal either the desired target position with respect to gaze direction or the motor error between gaze axis and reach target. The gaze-independent reach neurons, possibly operating in a shoulder- or arm-centered reference frame, might carry signals closer to motor output. Together these two types of reach neurons add evidence to our hypothesis that the SC is involved in the sensorimotor transformation for eye-hand coordination in primates.

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Coordination of Smooth Pursuit and Saccade Target Selection in Monkeys

Journal of Neurophysiology ◽

10.1152/jn.00021.2007 ◽

2007 ◽

Vol 98 (4) ◽

pp. 2206-2214 ◽

Cited By ~ 8

Author(s):

Gilbert R. Case ◽

Vincent P. Ferrera

Keyword(s):

Smooth Pursuit ◽

Target Selection ◽

Saccade Target ◽

Target Color ◽

Smooth Pursuit Eye Movements ◽

Moving Targets ◽

Neural Signals ◽

Pursuit Eye Movements ◽

Selection For ◽

Selection Signal

The coordination of saccadic and smooth pursuit eye movements in macaque monkeys was investigated using a target selection paradigm with two moving targets crossing at a center fixation point. A task in which monkeys selected a target based on its color was used to test the hypothesis that common neural signals underlie target selection for pursuit and saccades, as well as testing whether target selection signals are available to the saccade and pursuit systems simultaneously or sequentially. Several combinations of target color, speed, and direction were used. In all cases, smooth pursuit was highly selective for the rewarded target before any saccade occurred. On >80% of the trials, the saccade was directed toward the same target as both pre- and postsaccadic pursuit. The results favor a model in which a shared target selection signal is simultaneously available to both the saccade and pursuit systems, rather than a sequential model.

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Dissociating oculomotor contributions to spatial and feature-based selection

Journal of Neurophysiology ◽

10.1152/jn.00275.2013 ◽

2013 ◽

Vol 110 (7) ◽

pp. 1525-1534 ◽

Cited By ~ 17

Author(s):

Donatas Jonikaitis ◽

Jan Theeuwes

Keyword(s):

Visual Perception ◽

Target Location ◽

Target Selection ◽

Visual Selection ◽

Saccade Target ◽

Perceptual Discrimination ◽

Spatial Selection ◽

Feature Based ◽

Selection Mechanisms ◽

Saccade Preparation

Saccades not only deliver the high-resolution retinal image requisite for visual perception, but processing stages associated with saccade target selection affect visual perception even before the eye movement starts. These presaccadic effects are thought to arise from two visual selection mechanisms: spatial selection that enhances processing of the saccade target location and feature-based selection that enhances processing of the saccade target features. By measuring oculomotor performance and perceptual discrimination, we determined which selection mechanisms are associated with saccade preparation. We observed both feature-based and space-based selection during saccade preparation but found that feature-based selection was neither related to saccade initiation nor was it affected by simultaneously observed redistribution of spatial selection. We conclude that oculomotor selection biases visual selection only in a spatial, feature-unspecific manner.

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Reversal of a Distractor Effect on Saccade Target Selection After Superior Colliculus Inactivation

Journal of Neurophysiology ◽

10.1152/jn.00591.2007 ◽

2008 ◽

Vol 99 (5) ◽

pp. 2694-2702 ◽

Cited By ~ 14

Author(s):

Robert M. McPeek

Keyword(s):

Superior Colliculus ◽

Search Task ◽

Target Location ◽

Target Selection ◽

Saccade Target ◽

Search Array ◽

Distractor Effect ◽

Normal Trend ◽

Winner Take All ◽

Take All

Recent evidence indicates that inactivation of the primate superior colliculus (SC) results in an increase in saccade target-selection errors. The pattern of errors suggests that a winner-take-all competition selects the saccade goal and that SC inactivation perturbs this process by biasing the competition against stimuli in the inactivated field. To investigate this idea, the difficulty of target selection was manipulated in a color-oddity search task by varying the number of homogeneous distractors in the search array. Previous studies have shown that target selection is easier when a greater number of homogeneous distractors is present, due to perceptual grouping of the distractors. These results were replicated when testing with the SC intact. Surprisingly, during SC inactivation, this normal trend was reversed: target-selection performance declined significantly with more distractors, resulting in a greater proportion of errant saccades to distractors. Examination of the saccade endpoints indicates that after SC inactivation, many errant saccades were directed to distractors adjacent to the target. This pattern of results suggests that the salience signal used by the SC for target selection is relatively broad in spatial scope. As a result, when the area of the SC representing the target location is inactivated, distractors near the target are at a competitive advantage relative to more distant distractors and, consequently, are selected more often as the saccade goal. This contributes to the trend of worse performance with more distractors due to the greater proximity of distractors to the target.

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Arm Trajectory Modifications During Reaching Towards Visual Targets

Journal of Cognitive Neuroscience ◽

10.1162/jocn.1991.3.3.220 ◽

1991 ◽

Vol 3 (3) ◽

pp. 220-230 ◽

Cited By ~ 185

Author(s):

Tamar Flash ◽

Ealan Henis

Keyword(s):

Target Location ◽

Movement Time ◽

Sudden Change ◽

Motor Task ◽

Arm Movements ◽

Arm Movement ◽

Hand Motion ◽

Original Plan ◽

Human Arm ◽

Human Arm Movements

In this paper we study the question of how an aimed arm movement is modified in response to a sudden change in target location occurring during the reaction or movement time. Earlier monkey and human studies demonstrated that aimed arm movements can be elicited in quick succession, without appreciable delays in responding to the target displacement, beyond the normal reaction time. Nevertheless, it is not yet clear how this motor task is performed. A first guess is that when a new visual stimulus appears the old plan is aborted and a new one conceived. Upon analyzing human arm movements, however, we find that the observations can be well accounted for by a different movement modification scheme. It appears that a new plan is vectorially added to the original plan. Among the implications of this result is the possibility of parallel planning of elemental movements and further support for the idea that arm movements are internally represented in terms of hand motion through external space.

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Spatial suppression due to statistical regularities is driven by distractor suppression not by target activation

10.31234/osf.io/zbcjv ◽

2018 ◽

Author(s):

Michel Failing ◽

Benchi Wang ◽

Jan Theeuwes

Keyword(s):

High Probability ◽

Target Location ◽

Target Selection ◽

Visual Space ◽

Alternative Interpretation ◽

Distractor Location ◽

Target Presentation ◽

Statistical Regularities ◽

Low Probability ◽

Presentation Experiment

Where and what we attend to is not only determined by what we are currently looking for but also by what we have encountered in the past. Recent studies suggest that biasing the probability by which distractors appear at locations in visual space may lead to attentional suppression of high probability distractor locations which effectively reduces capture by a distractor but also impairs target selection at this location. However, in many of these studies introducing a high probability distractor location was tantamount to increasing the probability of the target appearing in any of the other locations (i.e. the low probability distractor locations). Here, we investigate an alternative interpretation of previous findings according to which attentional selection at high probability distractor locations is not suppressed. Instead, selection at low probability distractor locations is facilitated. In two visual search tasks, we found no evidence for this hypothesis: neither when there was only a bias in target presentation but no bias in distractor presentation (Experiment 1), nor when there was only a bias in distractor presentation but no bias in target presentation (Experiment 2). We conclude that recurrent presentation of a distractor in a specific location leads to attentional suppression of that location through a mechanism that is unaffected by any regularities regarding the target location.

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