Influence by self-motion speed to peripersonal space

How do we perceive object motion during self-motion using visual information alone? Previous studies have reported that the visual system can use optic flow to identify and globally subtract the retinal motion component resulting from self-motion to recover scene-relative object motion, a process called flow parsing. In this article, we developed a retinal motion nulling method to directly measure and quantify the magnitude of flow parsing (i.e., flow parsing gain) in various scenarios to examine the accuracy and tuning of flow parsing for the visual perception of object motion during self-motion. We found that flow parsing gains were below unity for all displays in all experiments; and that increasing self-motion and object motion speed did not alter flow parsing gain. We conclude that visual information alone is not sufficient for the accurate perception of scene-relative motion during self-motion. Although flow parsing performs global subtraction, its accuracy also depends on local motion information in the retinal vicinity of the moving object. Furthermore, the flow parsing gain was constant across common self-motion or object motion speeds. These results can be used to inform and validate computational models of flow parsing.

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Self-Motion Speed Perception of Visual Information in Driving: Modeling and Validation

Traffic and Transportation Studies 2010 ◽

10.1061/41123(383)97 ◽

2010 ◽

Cited By ~ 3

Author(s):

Hirofumi Yotsutsuji ◽

Hideyuki Kita

Keyword(s):

Visual Information ◽

Motion Speed ◽

Speed Perception ◽

Self Motion

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Speed tuning in the macaque posterior parietal cortex

10.1101/204966 ◽

2017 ◽

Author(s):

Eric Avila ◽

Kaushik J Lakshminarasimhan ◽

Gregory C DeAngelis ◽

Dora E Angelaki

Keyword(s):

Parietal Cortex ◽

Optic Flow ◽

Posterior Parietal Cortex ◽

Potential Role ◽

Motion Platform ◽

Neural Recordings ◽

Motion Speed ◽

Area 7A ◽

Posterior Parietal ◽

Self Motion

ABSTRACTNeurons in the macaque posterior parietal cortex are known to encode the direction of self-motion. But do they also encode one’s speed? To test this, we performed neural recordings from area 7a while monkeys were passively translated or rotated at various speeds. Visual stimuli were delivered as optic flow fields and vestibular stimuli were generated by a motion platform. Under both conditions, the responses of a fraction of neurons scaled linearly with self-motion speed, and speed-selective neurons were not localized to specific layers or columns. We analyzed ensembles of simultaneously recorded neurons and found that the precision of speed representation was sufficient to support path integration over modest distances. Our findings describe a multisensory neural code for linear and angular self-motion speed in the posterior parietal cortex of the macaque brain, and suggest a potential role for this representation.

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Perceptual Awareness of Optic Flows Paced Optimally and Non-optimally to Walking Speed

Perception ◽

10.1177/03010066211034368 ◽

2021 ◽

Vol 50 (9) ◽

pp. 797-818

Author(s):

Paweł Motyka ◽

Zuzanna Kozłowska ◽

Piotr Litwin

Keyword(s):

Visual Processing ◽

Walking Speed ◽

Visual Awareness ◽

Threshold Level ◽

Perceptual Awareness ◽

Flow Speeds ◽

Motion Speed ◽

Optic Flows ◽

Walking Speeds ◽

Self Motion

Previous research suggests that visual processing depends strongly on locomotor activity and is tuned to optic flows consistent with self-motion speed. Here, we used a binocular rivalry paradigm to investigate whether perceptual access to optic flows depends on their optimality in relation to walking velocity. Participants walked at two different speeds on a treadmill while viewing discrepant visualizations of a virtual tunnel in each eye. We hypothesized that visualizations paced appropriately to the walking speeds will be perceived longer than non optimal (too fast/slow) ones. The presented optic flow speeds were predetermined individually in a task based on matching visual speed to both walking velocities. In addition, perceptual preference for optimal optic flows was expected to increase with proprioceptive ability to detect threshold-level changes in walking speed. Whereas faster (more familiar) optic flows showed enhanced access to awareness during faster compared with slower walking conditions, for slower visual flows, only a nonsignificant tendency for the analogous effect was observed. These effects were not dependent on individual proprioceptive sensitivity. Our findings concur with the emerging view that the velocity of one’s locomotion is used to calibrate visual perception of self-motion and extend the scope of reported action effects on visual awareness.

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Perception of Self-Motion and Regulation of Walking Speed in Young-Old Adults

Motor Control ◽

10.1123/mc.2014-0010 ◽

2015 ◽

Vol 19 (3) ◽

pp. 191-206 ◽

Cited By ~ 4

Author(s):

Marie-Jasmine Lalonde-Parsi ◽

Anouk Lamontagne

Keyword(s):

Visual Motion ◽

Walking Speed ◽

Perceptual Task ◽

Old Adults ◽

Motion Speed ◽

Perception Of Self ◽

Speed Discrimination ◽

Self Motion ◽

The Relationship ◽

Young Old

Whether a reduced perception of self-motion contributes to poor walking speed adaptations in older adults is unknown. In this study, speed discrimination thresholds (perceptual task) and walking speed adaptations (walking task) were compared between young (19–27 years) and young-old individuals (63–74 years), and the relationship between the performance on the two tasks was examined. Participants were evaluated while viewing a virtual corridor in a helmet-mounted display. Speed discrimination thresholds were determined using a staircase procedure. Walking speed modulation was assessed on a self-paced treadmill while exposed to different self-motion speeds ranging from 0.25 to 2 times the participants’ comfortable speed. For each speed, participants were instructed to match the self-motion speed described by the moving corridor. On the walking task, participants displayed smaller walking speed errors at comfortable walking speeds compared with slower of faster speeds. The young-old adults presented larger speed discrimination thresholds (perceptual experiment) and larger walking speed errors (walking experiment) compared with young adults. Larger walking speed errors were associated with higher discrimination thresholds. The enhanced performance on the walking task at comfortable speed suggests that intersensory calibration processes are influenced by experience, hence optimized for frequently encountered conditions. The altered performance of the young-old adults on the perceptual and walking tasks, as well as the relationship observed between the two tasks, suggest that a poor perception of visual motion information may contribute to the poor walking speed adaptations that arise with aging.

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Individual Differences in the Flexibility of Peripersonal Space

Experimental Psychology (formerly Zeitschrift für Experimentelle Psychologie) ◽

10.1027/1618-3169/a000350 ◽

2017 ◽

Vol 64 (1) ◽

pp. 49-55 ◽

Cited By ~ 14

Author(s):

Samuel B. Hunley ◽

Arwen M. Marker ◽

Stella F. Lourenco

Keyword(s):

Individual Differences ◽

Peripersonal Space ◽

The Body ◽

Laser Pointer ◽

Baseline Measure ◽

Bisection Task ◽

Defensive Function ◽

Representational Space ◽

Laser Condition ◽

Line Bisection Task

Abstract. The current study investigated individual differences in the flexibility of peripersonal space (i.e., representational space near the body), specifically in relation to trait claustrophobic fear (i.e., fear of suffocating or being physically restricted). Participants completed a line bisection task with either a laser pointer (Laser condition), allowing for a baseline measure of the size of one’s peripersonal space, or a stick (Stick condition), which produces expansion of one’s peripersonal space. Our results revealed that individuals high in claustrophobic fear had larger peripersonal spaces than those lower in claustrophobic fear, replicating previous research. We also found that, whereas individuals low in claustrophobic fear demonstrated the expected expansion of peripersonal space in the Stick condition, individuals high in claustrophobic fear showed less expansion, suggesting decreased flexibility. We discuss these findings in relation to the defensive function of peripersonal space and reduced attentional flexibility associated with trait anxieties.

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