Refuting the hypothesis that a unilateral human parietal lesion abolishes saccade corollary discharge

Rath-Wilson, Kate; Guitton, Daniel

doi:10.1093/brain/awv275

Cited by 9 publications

(20 citation statements)

References 43 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Of course, requiring more time to complete the same task than healthy control participants should also be considered a deficit, but one of a different nature. Taken together, the studies by Fabius et al and Rath-Wilson and Guitton (Fabius et al, in press;Rath-Wilson & Guitton, 2015) show that although patients with PPC lesions can use extra-retinal information to maintain a stable sense of location across eye movements, they do not do so as efficiently as healthy participants, making both more variable and hypometric secondary saccades and more errors in their perceptual judgments.…”

mentioning

confidence: 88%

“…Although this clean-cut view has been very influential, later studies have put it into question. Rath-Wilson and Guitton (Rath-Wilson & Guitton, 2015) tested PPC patients in two variations of the double-step task: First, they allowed patients to perform multiple saccades by giving them more time to complete the saccadic sequence. Second, to minimize the possibility that the failure in the double-step task was due to a general deficit in maintaining spatial location in memory, they presented the target in reverse order and also had a condition in which only the second target was presented and the choice of the first saccade amplitude was self-determined by the patient.…”

mentioning

confidence: 99%

See 1 more Smart Citation

Uncertainty and spatial updating in posterior parietal cortex

Lisi

2020

Cortex

View full text Add to dashboard Cite

Vision is an active process that requires frequently reorienting the central, high-acuity part of the retina toward relevant objects in the world to enable further processing. About three times per second we make saccadic eye movements that shift the entire image on the retina, yet the world appears stable and we can effortlessly keep track of where things are. The question of how the brain achieves visual stability across eye movements (or self-motion in general) has fascinated many great thinkers, including von Helmholtz (von Helmholtz, 1867) who had already recognized that our sense of location must come from a synthesis of retinal coordinates with information about eye position and movement. In recent years much progress has been made in uncovering the neural and computational mechanisms of visual stability. From a computational point of view, modeling studies have shown how populations of neurons could maintain a stable mapping between an internal retinotopic representation and spatiotopic (world-centered) coordinates of objects in the world (Casarotti et al., 2012;Denève et al., 2007;Zipser & Andersen, 1988). These models rely either on proprioceptive signals from the eye to build an explicit spatiotopic map or on a copy of the motor command sent to move the eye, an efferent copy, that would be used to update the location of the target of interests on the internal retinotopic map. The latter mechanism can support a working spatiotopy that keeps track of locations across eye movements without postulating an explicit spatiotopic internal map. What concerns the neural mechanisms, a seminal study (Duhamel, Colby, et al., 1992) established a link between the processing of efferent copy signal and the posterior parietal cortex (PPC), by demonstrating the existence of neurons in the monkey lateral intraparietal area (LIP, which contains a retinotopic representation of the visual field) that, even before a saccade start, respond to the stimuli that will land in their receptive field after the eye movement. This result inspired investigations of visual stability in human patients with PPC damage (e.g. Heide et al., 1995;Vuilleumier et al., 2007), leading to the conclusion that an intact parietal cortex is crucial for maintaining a stable sense of location across eye movements. A new study by Fabius and colleagues (Fabius et al., in press) however, present data that challenge this conclusion and call instead for a more nuanced view about the role of PPC in visual stability.Many of the original studies on visual stability used an experimental protocol known as doublestep task. In this task, participants are asked to make two successive saccades toward the location of two sequentially flashed targets, both of which disappear before the first saccade begins. Thus,

show abstract

mentioning

confidence: 88%

mentioning

confidence: 99%

Uncertainty and spatial updating in posterior parietal cortex

Lisi

2020

Cortex

View full text Add to dashboard Cite

show abstract

“…When patients with parietal lesions attempt a double-step task, their greatest deficit is with the second saccade even though they can perform simple, sequential visually guided saccades to the same targets quite well (Duhamel et al 1992b, Heide et al 1995, Rath-Wilson & Guitton 2015). Simple visually guided saccades into the contralateral field have decreased velocity and increased latency, and they are less accurate than saccades into the ipsilateral field (subpanel i of Figure 5 b ).…”

Section: Neuropsychological Evidence For the Behavioral Significance mentioning

confidence: 99%

“…Suggestive evidence for a craniotopic representation comes from Rath-Wilson & Guitton (2015). They studied the performance of patients with lesions of the right parietal lobe in the double-step task.…”

Section: Psychophysical Evidence For a Craniotopic Representationmentioning

confidence: 99%

Corollary Discharge and Oculomotor Proprioception: Cortical Mechanisms for Spatially Accurate Vision

Sun

Goldberg

2016

Annu. Rev. Vis. Sci.

View full text Add to dashboard Cite

A classic problem in psychology is understanding how the brain creates a stable and accurate representation of space for perception and action despite a constantly moving eye. Two mechanisms have been proposed to solve this problem: Herman von Helmholtz’s idea that the brain uses a corollary discharge of the motor command that moves the eye to adjust the visual representation, and Sir Charles Sherrington’s idea that the brain measures eye position to calculate a spatial representation. Here, we discuss the cognitive, neuropsychological, and physiological mechanisms that support each of these ideas. We propose that both are correct: A rapid corollary discharge signal remaps the visual representation before an impending saccade, computing accurate movement vectors; and an oculomotor proprioceptive signal enables the brain to construct a more accurate craniotopic representation of space that develops slowly after the saccade.

show abstract

“…However, sensory feedback (i.e. proprioceptive inflow) may increasingly be used for larger saccade sequences (Poletti et al , 2013) or longer time intervals between eye movements (Rath-Wilson and Guitton, 2015).…”

mentioning

confidence: 99%