The Experts below are selected from a list of 5937 Experts worldwide ranked by ideXlab platform
Marisa Carrasco - One of the best experts on this subject based on the ideXlab platform.
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Oculomotor freezing reflects tactile temporal expectation and aids tactile perception
Nature Communications, 2020Co-Authors: Stephanie Badde, Caroline F Myers, Shlomit Yuvalgreenberg, Marisa CarrascoAbstract:The Oculomotor System keeps the eyes steady in expectation of visual events. Here, recording microsaccades while people performed a tactile, frequency discrimination task enabled us to test whether the Oculomotor System shows an analogous preparatory response for unrelated tactile events. We manipulated the temporal predictability of tactile targets using tactile cues, which preceded the target by either constant (high predictability) or variable (low predictability) time intervals. We find that microsaccades are inhibited prior to tactile targets and more so for constant than variable intervals, revealing a tight crossmodal link between tactile temporal expectation and Oculomotor action. These findings portray Oculomotor freezing as a marker of crossmodal temporal expectation. Moreover, microsaccades occurring around the tactile target presentation are associated with reduced task performance, suggesting that Oculomotor freezing mitigates potential detrimental, concomitant effects of microsaccades and revealing a crossmodal coupling between tactile perception and Oculomotor action.
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Oculomotor freezing reflects tactile temporal expectation and aids tactile perception
bioRxiv, 2020Co-Authors: Stephanie Badde, Caroline F Myers, Shlomit Yuvalgreenberg, Marisa CarrascoAbstract:The Oculomotor System keeps the eyes steady in expectation of visual events. Here, recording microsaccades while people performed a tactile (frequency discrimination) task enabled us to test whether the Oculomotor System shows an analogous preparatory response for unrelated tactile events. We manipulated the temporal predictability of tactile targets using tactile cues, which preceded the target by either constant (high predictability) or variable (low predictability) time intervals. Microsaccades were inhibited prior to target onset and more so for constant than variable intervals. This microsaccadic inhibition reveals a tight cross-modal link between tactile temporal expectation and Oculomotor action. These findings -together with parallel findings in audition- portray Oculomotor freezing as a marker of supramodal temporal expectation. Moreover, microsaccades occurring around the tactile target presentation were associated with reduced task performance, suggesting that Oculomotor freezing mitigates potential detrimental, concomitant effects of microsaccades and revealing a cross-modal coupling between tactile perception and Oculomotor action.
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Oculomotor freezing reflects tactile temporal expectation and aids tactile perception
'Springer Science and Business Media LLC', 2020Co-Authors: Stephanie Badde, Caroline F Myers, Shlomit Yuval-greenberg, Marisa CarrascoAbstract:The Oculomotor System keeps the eyes steady in expectation of visual events, inhibiting small fixational eye movements. Here, the authors reveal that this Oculomotor freezing reflects tactile temporal expectations and aids tactile perception
Stephanie Badde - One of the best experts on this subject based on the ideXlab platform.
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Oculomotor freezing reflects tactile temporal expectation and aids tactile perception
Nature Communications, 2020Co-Authors: Stephanie Badde, Caroline F Myers, Shlomit Yuvalgreenberg, Marisa CarrascoAbstract:The Oculomotor System keeps the eyes steady in expectation of visual events. Here, recording microsaccades while people performed a tactile, frequency discrimination task enabled us to test whether the Oculomotor System shows an analogous preparatory response for unrelated tactile events. We manipulated the temporal predictability of tactile targets using tactile cues, which preceded the target by either constant (high predictability) or variable (low predictability) time intervals. We find that microsaccades are inhibited prior to tactile targets and more so for constant than variable intervals, revealing a tight crossmodal link between tactile temporal expectation and Oculomotor action. These findings portray Oculomotor freezing as a marker of crossmodal temporal expectation. Moreover, microsaccades occurring around the tactile target presentation are associated with reduced task performance, suggesting that Oculomotor freezing mitigates potential detrimental, concomitant effects of microsaccades and revealing a crossmodal coupling between tactile perception and Oculomotor action.
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Oculomotor freezing reflects tactile temporal expectation and aids tactile perception
bioRxiv, 2020Co-Authors: Stephanie Badde, Caroline F Myers, Shlomit Yuvalgreenberg, Marisa CarrascoAbstract:The Oculomotor System keeps the eyes steady in expectation of visual events. Here, recording microsaccades while people performed a tactile (frequency discrimination) task enabled us to test whether the Oculomotor System shows an analogous preparatory response for unrelated tactile events. We manipulated the temporal predictability of tactile targets using tactile cues, which preceded the target by either constant (high predictability) or variable (low predictability) time intervals. Microsaccades were inhibited prior to target onset and more so for constant than variable intervals. This microsaccadic inhibition reveals a tight cross-modal link between tactile temporal expectation and Oculomotor action. These findings -together with parallel findings in audition- portray Oculomotor freezing as a marker of supramodal temporal expectation. Moreover, microsaccades occurring around the tactile target presentation were associated with reduced task performance, suggesting that Oculomotor freezing mitigates potential detrimental, concomitant effects of microsaccades and revealing a cross-modal coupling between tactile perception and Oculomotor action.
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Oculomotor freezing reflects tactile temporal expectation and aids tactile perception
'Springer Science and Business Media LLC', 2020Co-Authors: Stephanie Badde, Caroline F Myers, Shlomit Yuval-greenberg, Marisa CarrascoAbstract:The Oculomotor System keeps the eyes steady in expectation of visual events, inhibiting small fixational eye movements. Here, the authors reveal that this Oculomotor freezing reflects tactile temporal expectations and aids tactile perception
Sara Morcuende - One of the best experts on this subject based on the ideXlab platform.
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neuroprotective effect of vascular endothelial growth factor on motoneurons of the Oculomotor System
International Journal of Molecular Sciences, 2021Co-Authors: Silvia Silvahucha, Angel M Pastor, Sara MorcuendeAbstract:Vascular endothelial growth factor (VEGF) was initially characterized as a potent angiogenic factor based on its activity on the vascular System. However, it is now well established that VEGF also plays a crucial role as a neuroprotective factor in the nervous System. A deficit of VEGF has been related to motoneuronal degeneration, such as that occurring in amyotrophic lateral sclerosis (ALS). Strikingly, motoneurons of the Oculomotor System show lesser vulnerability to neurodegeneration in ALS compared to other motoneurons. These motoneurons presented higher amounts of VEGF and its receptor Flk-1 than other brainstem pools. That higher VEGF level could be due to an enhanced retrograde input from their target muscles, but it can also be produced by the motoneurons themselves and act in an autocrine way. By contrast, VEGF's paracrine supply from the vicinity cells, such as glial cells, seems to represent a minor source of VEGF for brainstem motoneurons. In addition, ocular motoneurons experiment an increase in VEGF and Flk-1 level in response to axotomy, not observed in facial or hypoglossal motoneurons. Therefore, in this review, we summarize the differences in VEGF availability that could contribute to the higher resistance of extraocular motoneurons to injury and neurodegenerative diseases.
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functional diversity of neurotrophin actions on the Oculomotor System
International Journal of Molecular Sciences, 2016Co-Authors: Beatriz Beniteztemino, Maria Davislopez A De Carrizosa, Sara Morcuende, Esperanza R Matarredona, Rosa R De La Cruz, Angel M PastorAbstract:Neurotrophins play a principal role in neuronal survival and differentiation during development, but also in the maintenance of appropriate adult neuronal circuits and phenotypes. In the Oculomotor System, we have demonstrated that neurotrophins are key regulators of developing and adult neuronal properties, but with peculiarities depending on each neurotrophin. For instance, the administration of NGF (nerve growth factor), BDNF (brain-derived neurotrophic factor) or NT-3 (neurotrophin-3) protects neonatal extraocular motoneurons from cell death after axotomy, but only NGF and BDNF prevent the downregulation in ChAT (choline acetyltransferase). In the adult, in vivo recordings of axotomized extraocular motoneurons have demonstrated that the delivery of NGF, BDNF or NT-3 recovers different components of the firing discharge activity of these cells, with some particularities in the case of NGF. All neurotrophins have also synaptotrophic activity, although to different degrees. Accordingly, neurotrophins can restore the axotomy-induced alterations acting selectively on different properties of the motoneuron. In this review, we summarize these evidences and discuss them in the context of other motor Systems.
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transynaptic effects of tetanus neurotoxin in the Oculomotor System
Brain, 2005Co-Authors: David Gonzalezforero, Sara Morcuende, Rosa R De La Cruz, Francisco J Alvarez, Angel M PastorAbstract:The question whether general tetanus arises from the independent sum of multiple local tetani or results from the actions of the transynaptic tetanus neurotoxin (TeNT) in higher brain centres remains unresolved. Despite the blood-borne dissemination of TeNT from an infected wound, the access to the central nervous System is probably prevented by the blood-brain barrier. However, several long-term sequelae (e.g. autonomic dysfunction, seizures, myoclonus, and sleep disturbances) present after the subsidence of muscle spasms might be indicative of central actions that occur farther away from lower motoneurons. Subsequently, the obvious entry route is the peripheral neurons followed by the transynaptic passage to the brain. We aimed at describing the pathophysiological correlates of TeNT translocation using the Oculomotor System as a comprehensive model of cell connectivity and neuronal firing properties. In this study, we report that injection of TeNT into the medial rectus muscle of one eye resulted in bilateral gaze palsy attributed to firing alterations found in the contralaterally projecting abducens internuclear neurons. Functional alterations in the abducens-to-Oculomotor internuclear pathway resembled in part the classically described TeNT disinhibition. We confirmed the transynaptic targeted action of TeNT by analysing vesicle-associated membrane protein2 (VAMP2) immunoreactivity (the SNARE protein cleaved by TeNT). VAMP2 immunoreactivity decreased by 94.4% in the Oculomotor nucleus (the first synaptic relay) and by 62.1% presynaptic to abducens neurons (the second synaptic relay). These results are the first demonstration of physiological changes in chains of connected neurons that are best explained by the transynaptic action of TeNT on premotor neurons as shown with VAMP2 immunoreactivity which serves as an indicator of TeNT activity.
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Expression of Trk receptors in the Oculomotor System of the adult cat.
Journal of Comparative Neurology, 2004Co-Authors: Beatriz Benítez-temiño, Sara Morcuende, Rosa R De La Cruz, George Z. Mentis, Angel M PastorAbstract:Laboratory of Neural Control, National Institute of Neurological Disorders and Stroke,National Institutes of Health, Bethesda, Maryland, 20892ABSTRACTWe examined the expression of the three Trk receptors for neurotrophins (TrkA, TrkB,and TrkC) in the extraocular motor nuclei of the adult cat by using antibodies directedagainst the full-Trk proteins in combination with horseradish peroxidase retrograde tracing.The three receptors were present in all neuronal populations investigated, including abdu-cens motoneurons and internuclear neurons, medial rectus motoneurons of the Oculomotornucleus, and trochlear motoneurons. They were also present in the vestibular and prepositushypoglossi nuclei. TrkA, TrkB, and TrkC immunopositive cells were found in similar per-centages in the Oculomotor and in the trochlear nuclei. In the abducens nucleus, however, asignificantly higher percentage of cells expressed TrkB than the other two receptors, amongboth motoneurons (81.8%) and internuclear neurons (88.4%). The percentages obtained forthe three Trk receptors in identified neuronal populations pointed to the colocalization of twoor three receptors in a large number of cells. We used confocal microscopy to elucidate thesubcellular location of Trk receptors. In this case, abducens motoneurons and internuclearneurons were identified with antibodies against choline acetyltransferase and calretinin,respectively. We found a different pattern of staining for each neurotrophin receptor, sug-gesting the possibility that each receptor and its cognate ligand may use a different route forcellular signaling. Therefore, the expression of Trk receptors in Oculomotor, trochlear, andabducens motoneurons, as well as abducens internuclear neurons, suggests that their asso-ciated neurotrophins may exert an influence on the normal operation of the Oculomotorcircuitry. The presence of multiple Trk receptors on individual cells indicates that they likelyact in concert with each other to regulate distinct functions. J. Comp. Neurol. 473:538–552,2004.
Angel M Pastor - One of the best experts on this subject based on the ideXlab platform.
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neuroprotective effect of vascular endothelial growth factor on motoneurons of the Oculomotor System
International Journal of Molecular Sciences, 2021Co-Authors: Silvia Silvahucha, Angel M Pastor, Sara MorcuendeAbstract:Vascular endothelial growth factor (VEGF) was initially characterized as a potent angiogenic factor based on its activity on the vascular System. However, it is now well established that VEGF also plays a crucial role as a neuroprotective factor in the nervous System. A deficit of VEGF has been related to motoneuronal degeneration, such as that occurring in amyotrophic lateral sclerosis (ALS). Strikingly, motoneurons of the Oculomotor System show lesser vulnerability to neurodegeneration in ALS compared to other motoneurons. These motoneurons presented higher amounts of VEGF and its receptor Flk-1 than other brainstem pools. That higher VEGF level could be due to an enhanced retrograde input from their target muscles, but it can also be produced by the motoneurons themselves and act in an autocrine way. By contrast, VEGF's paracrine supply from the vicinity cells, such as glial cells, seems to represent a minor source of VEGF for brainstem motoneurons. In addition, ocular motoneurons experiment an increase in VEGF and Flk-1 level in response to axotomy, not observed in facial or hypoglossal motoneurons. Therefore, in this review, we summarize the differences in VEGF availability that could contribute to the higher resistance of extraocular motoneurons to injury and neurodegenerative diseases.
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Functional diversity of motoneurons in the Oculomotor System.
Proceedings of the National Academy of Sciences of the United States of America, 2019Co-Authors: Rosendo G. Hernández, Rosa R De La Cruz, Paula M. Calvo, Roland Blumer, Angel M PastorAbstract:Extraocular muscles contain two types of muscle fibers according to their innervation pattern: singly innervated muscle fibers (SIFs), similar to most skeletal muscle fibers, and multiply innervated muscle fibers (MIFs). Morphological studies have revealed that SIF and MIF motoneurons are segregated anatomically and receive different proportions of certain afferents, suggesting that while SIF motoneurons would participate in the whole repertoire of eye movements, MIF motoneurons would contribute only to slow eye movements and fixations. We have tested that proposal by performing single-unit recordings, in alert behaving cats, of electrophysiologically identified MIF and SIF motoneurons in the abducens nucleus. Our results show that both types of motoneuron discharge in relation to eye position and velocity, displaying a tonic–phasic firing pattern for different types of eye movement (saccades, vestibulo-ocular reflex, vergence) and gaze-holding. However, MIF motoneurons presented an overall reduced firing rate compared with SIF motoneurons, and had significantly lower recruitment threshold and also lower eye position and velocity sensitivities. Accordingly, MIF motoneurons could control mainly gaze in the off-direction, when less force is needed, whereas SIF motoneurons would contribute to increase muscle tension progressively toward the on-direction as more force is required. Anatomically, MIF and SIF motoneurons distributed intermingled within the abducens nucleus, with MIF motoneurons being smaller and having a lesser somatic synaptic coverage. Our data demonstrate the functional participation of both MIF and SIF motoneurons in fixations and slow and phasic eye movements, although their discharge properties indicate a functional segregation.
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functional diversity of neurotrophin actions on the Oculomotor System
International Journal of Molecular Sciences, 2016Co-Authors: Beatriz Beniteztemino, Maria Davislopez A De Carrizosa, Sara Morcuende, Esperanza R Matarredona, Rosa R De La Cruz, Angel M PastorAbstract:Neurotrophins play a principal role in neuronal survival and differentiation during development, but also in the maintenance of appropriate adult neuronal circuits and phenotypes. In the Oculomotor System, we have demonstrated that neurotrophins are key regulators of developing and adult neuronal properties, but with peculiarities depending on each neurotrophin. For instance, the administration of NGF (nerve growth factor), BDNF (brain-derived neurotrophic factor) or NT-3 (neurotrophin-3) protects neonatal extraocular motoneurons from cell death after axotomy, but only NGF and BDNF prevent the downregulation in ChAT (choline acetyltransferase). In the adult, in vivo recordings of axotomized extraocular motoneurons have demonstrated that the delivery of NGF, BDNF or NT-3 recovers different components of the firing discharge activity of these cells, with some particularities in the case of NGF. All neurotrophins have also synaptotrophic activity, although to different degrees. Accordingly, neurotrophins can restore the axotomy-induced alterations acting selectively on different properties of the motoneuron. In this review, we summarize these evidences and discuss them in the context of other motor Systems.
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transynaptic effects of tetanus neurotoxin in the Oculomotor System
Brain, 2005Co-Authors: David Gonzalezforero, Sara Morcuende, Rosa R De La Cruz, Francisco J Alvarez, Angel M PastorAbstract:The question whether general tetanus arises from the independent sum of multiple local tetani or results from the actions of the transynaptic tetanus neurotoxin (TeNT) in higher brain centres remains unresolved. Despite the blood-borne dissemination of TeNT from an infected wound, the access to the central nervous System is probably prevented by the blood-brain barrier. However, several long-term sequelae (e.g. autonomic dysfunction, seizures, myoclonus, and sleep disturbances) present after the subsidence of muscle spasms might be indicative of central actions that occur farther away from lower motoneurons. Subsequently, the obvious entry route is the peripheral neurons followed by the transynaptic passage to the brain. We aimed at describing the pathophysiological correlates of TeNT translocation using the Oculomotor System as a comprehensive model of cell connectivity and neuronal firing properties. In this study, we report that injection of TeNT into the medial rectus muscle of one eye resulted in bilateral gaze palsy attributed to firing alterations found in the contralaterally projecting abducens internuclear neurons. Functional alterations in the abducens-to-Oculomotor internuclear pathway resembled in part the classically described TeNT disinhibition. We confirmed the transynaptic targeted action of TeNT by analysing vesicle-associated membrane protein2 (VAMP2) immunoreactivity (the SNARE protein cleaved by TeNT). VAMP2 immunoreactivity decreased by 94.4% in the Oculomotor nucleus (the first synaptic relay) and by 62.1% presynaptic to abducens neurons (the second synaptic relay). These results are the first demonstration of physiological changes in chains of connected neurons that are best explained by the transynaptic action of TeNT on premotor neurons as shown with VAMP2 immunoreactivity which serves as an indicator of TeNT activity.
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Expression of Trk receptors in the Oculomotor System of the adult cat.
Journal of Comparative Neurology, 2004Co-Authors: Beatriz Benítez-temiño, Sara Morcuende, Rosa R De La Cruz, George Z. Mentis, Angel M PastorAbstract:Laboratory of Neural Control, National Institute of Neurological Disorders and Stroke,National Institutes of Health, Bethesda, Maryland, 20892ABSTRACTWe examined the expression of the three Trk receptors for neurotrophins (TrkA, TrkB,and TrkC) in the extraocular motor nuclei of the adult cat by using antibodies directedagainst the full-Trk proteins in combination with horseradish peroxidase retrograde tracing.The three receptors were present in all neuronal populations investigated, including abdu-cens motoneurons and internuclear neurons, medial rectus motoneurons of the Oculomotornucleus, and trochlear motoneurons. They were also present in the vestibular and prepositushypoglossi nuclei. TrkA, TrkB, and TrkC immunopositive cells were found in similar per-centages in the Oculomotor and in the trochlear nuclei. In the abducens nucleus, however, asignificantly higher percentage of cells expressed TrkB than the other two receptors, amongboth motoneurons (81.8%) and internuclear neurons (88.4%). The percentages obtained forthe three Trk receptors in identified neuronal populations pointed to the colocalization of twoor three receptors in a large number of cells. We used confocal microscopy to elucidate thesubcellular location of Trk receptors. In this case, abducens motoneurons and internuclearneurons were identified with antibodies against choline acetyltransferase and calretinin,respectively. We found a different pattern of staining for each neurotrophin receptor, sug-gesting the possibility that each receptor and its cognate ligand may use a different route forcellular signaling. Therefore, the expression of Trk receptors in Oculomotor, trochlear, andabducens motoneurons, as well as abducens internuclear neurons, suggests that their asso-ciated neurotrophins may exert an influence on the normal operation of the Oculomotorcircuitry. The presence of multiple Trk receptors on individual cells indicates that they likelyact in concert with each other to regulate distinct functions. J. Comp. Neurol. 473:538–552,2004.
Artem V Belopolsky - One of the best experts on this subject based on the ideXlab platform.
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detection of object displacement during a saccade is prioritized by the Oculomotor System
Journal of Vision, 2019Co-Authors: Jonathan Van Leeuwen, Artem V BelopolskyAbstract:The human eye-movement System is equipped with a sophisticated updating mechanism that can adjust for large retinal displacements produced by saccadic eye movements. The nature of this updating mechanism is still highly debated. Previous studies have demonstrated that updating can occur very rapidly and is initiated before the start of a saccade. In the present study, we used saccade curvature to demonstrate that the Oculomotor System is tuned for detecting object displacements during saccades. Participants made a sequence of saccades while ignoring an irrelevant distractor. Curvature of the second saccade relative to the distractor was used to estimate the time course of updating. Saccade curvature away from the presaccadic location of the distractor emerged as early as 80 ms after the first saccade when the distractor was displaced during a saccade. This is about 50 ms earlier than when a distractor was only present before a saccade, only present after a saccade, or remained stationary across a saccade. This shows that the Oculomotor System prioritizes detection of object displacements during saccades, which may be useful for guiding corrective saccades. The results also challenge previous views by demonstrating the additional role of postsaccadic information in updating target-distractor competition across saccades.
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eye abduction reduces but does not eliminate competition in the Oculomotor System
Journal of Vision, 2017Co-Authors: Paul J Boon, Jan Theeuwes, Artem V BelopolskyAbstract:Although it is well established that there is a tight coupling between covert attention and the eye movement System there is an ongoing controversy whether this relationship is functional. Previous studies demonstrated that disrupting the ability to execute an eye movement interferes with the allocation of covert attention. One technique that prevents the execution of an eye movement involves the abduction of the eye in the orbit while presenting the stimuli outside of the effective Oculomotor range (Craighero, Nascimben, & Fadiga, 2004). Although eye abduction is supposed to disrupt activation of the Oculomotor program responsible for the shift of covert attention, this crucial assumption has never been tested experimentally. In the present study we used saccadic curvature to examine whether eye abduction eliminates the target-distractor competition in the Oculomotor System. We experimentally reduced the ability to execute saccades by abducting the eye by 30° (monocular vision). This way the peripheral part of the temporal hemifield was located outside the Oculomotor range. Participants made a vertical eye movement while on some trials a distractor was shown either inside or outside of the Oculomotor range. The curvature away from distractors located outside the Oculomotor range was reduced, but not completely eliminated. This confirms that eye abduction influences the activation of the Oculomotor program, but points to the fact that other forms of motor planning, such as head movements are also represented in the Oculomotor System. The results are in line with the idea that covert attention is an emerging property of movement planning, but is not restricted to saccade planning.
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the role of the Oculomotor System in updating visual spatial working memory across saccades
PLOS ONE, 2016Co-Authors: Paul J Boon, Artem V Belopolsky, Jan TheeuwesAbstract:Visual-spatial working memory (VSWM) helps us to maintain and manipulate visual information in the absence of sensory input. It has been proposed that VSWM is an emergent property of the Oculomotor System. In the present study we investigated the role of the Oculomotor System in updating of spatial working memory representations across saccades. Participants had to maintain a location in memory while making a saccade to a different location. During the saccade the target was displaced, which went unnoticed by the participants. After executing the saccade, participants had to indicate the memorized location. If memory updating fully relies on cancellation driven by extraretinal Oculomotor signals, the displacement should have no effect on the perceived location of the memorized stimulus. However, if postsaccadic retinal information about the location of the saccade target is used, the perceived location will be shifted according to the target displacement. As it has been suggested that maintenance of accurate spatial representations across saccades is especially important for action control, we used different ways of reporting the location held in memory; a match-to-sample task, a mouse click or by making another saccade. The results showed a small Systematic target displacement bias in all response modalities. Parametric manipulation of the distance between the to-be-memorized stimulus and saccade target revealed that target displacement bias increased over time and changed its spatial profile from being initially centered on locations around the saccade target to becoming spatially global. Taken together results suggest that we neither rely exclusively on extraretinal nor on retinal information in updating working memory representations across saccades. The relative contribution of retinal signals is not fixed but depends on both the time available to integrate these signals as well as the distance between the saccade target and the remembered location.
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common priority map for selection history reward and emotion in the Oculomotor System
Perception, 2015Co-Authors: Artem V BelopolskyAbstract:In natural scenes, many objects compete for visual selection. However, it is not always clear why certain objects win this competition. I will demonstrate that the eye movement System lives in a constant state of competition among different Oculomotor programs. This competition is not limited to the competition between the current goals of the observer and salient objects in the environment but incorporates independent influences from memory, reward, and emotional Systems. These involuntary and automatic biases often overcome the goal-directed selection and expose severe limits in goal-driven control. There is also a striking similarity in the way that these very different sources of bias activate the Oculomotor System and compete for representation. The inputs from various information sources are integrated in the common map in the Oculomotor System for the sole purpose of improving the efficiency of Oculomotor selection.
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target distractor competition in the Oculomotor System is spatiotopic
The Journal of Neuroscience, 2014Co-Authors: Donatas Jonikaitis, Artem V BelopolskyAbstract:In natural scenes, multiple visual stimuli compete for selection; however, each saccade displaces the stimulus representations in retinotopicaly organized visual and Oculomotor maps. In the present study, we used saccade curvature to investigate whether Oculomotor competition across eye movements is represented in retinotopic or spatiotopic coordinates. Participants performed a sequence of saccades and we induced Oculomotor competition by briefly presenting a task-irrelevant distractor at different times during the saccade sequence. Despite the intervening saccade, the second saccade curved away from a spatial representation of the distractor that was presented before the first saccade. Furthermore, the degree of saccade curvature increased with the salience of the distractor presented before the first saccade. The results suggest that spatiotopic representations of target-distractor competition are crucial for successful interaction with objects of interest despite the intervening eye movements.
