Bimanual and unimanual length perception

Panday, Virjanand; Tiest, Wouter M. Bergmann; Kappers, Astrid M. L.

doi:10.1007/s00221-014-3974-1

Cited by 9 publications

(9 citation statements)

References 22 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…To summarize, we found that tactile motion showed an expansion of the spacing within the hand compared to that between the hands. This is consistent with the greater precision of movement and length judgment within the hand as opposed to across hands (Panday et al., 2014; Smeets & Brenner, 2001; Tresilian & Stelmach, 1997). It is opposite to what would be expected if stimuli on the same hand were grouped and therefore seen as being closer together (Coren & Girgus, 1980).…”

Section: Discussionsupporting

confidence: 78%

“…This unimanual versus bimanual bias for length judgments has not been reported previously. Panday et al. (2014) did report that within-hand judgments were less variable than between-hand judgments, but they did not compare the magnitudes of the unimanual versus bimanual estimates.…”

Section: Resultsmentioning

confidence: 99%

“…There are two that compared unimanual versus bimanual grasping (Smeets & Brenner, 2001; Tresilian & Stelmach, 1997) and found that grasping is more precise in the unimanual case. One study that did look at unimanual versus bimanual length estimates (Panday, Bergmann Tiest, & Kappers, 2014) reported only that the within-hand judgments were, unsurprisingly, less variable than the between-hand judgments. They did not compare the magnitude of the length estimate—our study is the first to do so.…”

Section: Experiments 1: Tactile Quartet Motionmentioning

confidence: 99%

See 2 more Smart Citations

The Tactile Quartet: Comparing Ambiguous Apparent Motion in Tactile and Visual Stimuli

et al. 2019

View full text Add to dashboard Cite

In the visual quartet, alternating diagonal pairs of dots produce apparent motion horizontally or vertically, depending on proximity. Here, we studied a tactile quartet where vibrating tactors were attached to the thumbs and index fingers of both hands. Apparent motion was felt either within hands (from index finger to thumb) or between hands. Participants adjusted the distance between their hands to find the point where motion changed directions. Surprisingly, switchovers occurred when between-hand distances were as much as twice that of within-hand distances—a general bias that was also found for tactile judgments of static distances. This expansion of within-hand felt distances was again seen when lights were placed on the hands rather than vibrating tactors. Importantly, switchover points were similar when the hands were placed at different depths, indicating that representations governing tactile motion were in perceptual three-dimensional space, not retinal two-dimensional space. This was true whether the quartets were visual stimuli on the hands or were purely visual on a monitor, suggesting that proximity is generally determined in three-dimensional coordinates for motion perception. Finally, the similarity of visual and tactile results suggests a common computation for apparent motion, albeit with different built-in distance biases for separate modalities.

show abstract

Section: Discussionsupporting

confidence: 78%

Section: Resultsmentioning

confidence: 99%

Section: Experiments 1: Tactile Quartet Motionmentioning

confidence: 99%

See 1 more Smart Citation

The Tactile Quartet: Comparing Ambiguous Apparent Motion in Tactile and Visual Stimuli

et al. 2019

View full text Add to dashboard Cite

show abstract

“…Spatial integration occurs when information from different body locations is combined. In [177], the authors investigated whether different ways of spatial integration lead to the same or different perceptions of length, by comparing different ways of discriminating length using two fingers, either of the same hand (thumb and index finger) or of the different hands (both index fingers). Results showed that the unimanual and the bimanual grasping conditions yielded best performance.…”

Section: Hand Synergies: Sensingmentioning

confidence: 99%

Hand synergies: Integration of robotics and neuroscience for understanding the control of biological and artificial hands

Santello

Bianchi

Gabiccini

et al. 2016

Physics of Life Reviews

213

160

View full text Add to dashboard Cite

The term ‘synergy’ – from the Greek synergia – means ‘working together’. The concept of multiple elements working together towards a common goal has been extensively used in neuroscience to develop theoretical frameworks, experimental approaches, and analytical techniques to understand neural control of movement, and for applications for neuro-rehabilitation. In the past decade, roboticists have successfully applied the framework of synergies to create novel design and control concepts for artificial hands, i.e., robotic hands and prostheses. At the same time, robotic research on the sensorimotor integration underlying the control and sensing of artificial hands has inspired new research approaches in neuroscience, and has provided useful instruments for novel experiments. The ambitious goal of integrating expertise and research approaches in robotics and neuroscience to study the properties and applications of the concept of synergies is generating a number of multidisciplinary cooperative projects, among which the recently finished 4-year European project “The Hand Embodied” (THE). This paper reviews the main insights provided by this framework. Specifically, we provide an overview of neuroscientific bases of hand synergies and introduce how robotics has leveraged the insights from neuroscience for innovative design in hardware and controllers for biomedical engineering applications, including myoelectric hand prostheses, devices for haptics research, and wearable sensing of human hand kinematics. The review also emphasizes how this multidisciplinary collaboration has generated new ways to conceptualize a synergy-based approach for robotics, and provides guidelines and principles for analyzing human behavior and synthesizing artificial robotic systems based on a theory of synergies.

show abstract

“…; Panday et al . ), and the neural computations required to form and update these two frames of reference may differ and influence subsequent perceptual judgments (Panday et al . ).…”

Section: Introductionmentioning

confidence: 99%

Stability of perception of the hand's aperture in a grasp

Butler

Héroux

Eijk

et al. 2019

The Journal of Physiology

View full text Add to dashboard Cite

Key points How we judge the location of our body parts can be affected by a range of factors that change how our brain interprets proprioceptive signals. We examined the effect of several such factors on how we perceive an object's width and the spacing between our thumb and fingers when grasping. Grasp‐related perceptions were slightly wider when using all digits, in line with our tendency to grasp larger objects with the entire hand. Surprisingly, these perceptions were not affected by the frames of reference for judgements (object width versus grasp aperture), whether the object was grasped actively or passively, or the strength of the grasp. These results show that the brain maintains a largely stable representation of the hand when grasping stationary objects. This stability may underpin our dexterity when grasping a vast array of objects. Abstract Various factors can alter how the brain interprets proprioceptive signals, leading to errors in how we perceive our body and execute motor tasks. This study determined the effect of critical factors on hand‐based perceptions. In Experiment 1, 20 participants grasped without lifting an unseen 6.5 cm‐wide object with two grasp configurations: thumb and all fingers, and thumb and index finger. Participants reported perceived grasp aperture (body reference frame) or perceived object width (external reference frame) using visual charts. In Experiment 2, 20 participants grasped the object with three grasp intensities (1, 5 and 15% maximal grasp force) actively or passively and reported perceived grasp aperture. A follow‐up experiment addressed whether results from Experiment 2 were influenced by the external force applied during passive grasp. Overall, there was a mean difference of 0.38 cm (95% confidence interval (CI), 0.12 to 0.63) between the two grasp configurations (all digits compared to thumb and index finger). Perceived object width compared to perceived grasp aperture differed by only −0.04 cm (95% CI, −0.30 to 0.21). There was no real effect of grasp intensity on perceived grasp aperture (−0.01 cm; 95% CI, −0.03 to 0.01) or grasp type (active versus passive; 0.18 cm; 95% CI, −0.19 to 0.55). Overall, grasp‐related perceptions are slightly wider when using all digits, in line with our tendency to grasp larger objects with the entire hand. The other factors – frame of reference, grasp intensity and grasp type – had no meaningful effect on these perceptions. These results provide evidence that the brain maintains a largely stable representation of the hand.

show abstract

Bimanual and unimanual length perception

Cited by 9 publications

References 22 publications

The Tactile Quartet: Comparing Ambiguous Apparent Motion in Tactile and Visual Stimuli

The Tactile Quartet: Comparing Ambiguous Apparent Motion in Tactile and Visual Stimuli

Hand synergies: Integration of robotics and neuroscience for understanding the control of biological and artificial hands

Stability of perception of the hand's aperture in a grasp

Contact Info

Product

Resources

About