Influence of the Stabilogram and Statokinesigram Visual Feedback upon the Body Oscillations

Extending the body with a tool could imply that characteristics of hand movements become characteristics of the movement of the effective part of the tool. Recent research suggests that such distal shifts are subject to boundary conditions. Here we propose the existence of three constraints: a strategy constraint, a constraint of movement characteristics, and a constraint of mode of control. We investigate their validity for the curvature of transverse movements aimed at a target while using a sliding first-order lever. Participants moved the tip of the effort arm of a real or virtual lever to control a cursor representing movements of the tip of the load arm of the lever on a monitor. With this tool, straight transverse hand movements are associated with concave curvature of the path of the tip of the tool. With terminal visual feedback and when targets were presented for the hand, hand paths were slightly concave in the absence of the dynamic transformation of the tool and slightly convex in its presence. When targets were presented for the tip of the lever, both the concave and convex curvatures of the hand paths became stronger. Finally, with continuous visual feedback of the tip of the lever, curvature of hand paths became convex and concave curvature of the paths of the tip of the lever was reduced. In addition, the effect of the dynamic transformation on curvature was attenuated. These findings support the notion that distal shifts are subject to at least the three proposed constraints.

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Development of Stimulator Based on Audio-Visual Feedback Signal

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.568-570.359 ◽

2014 ◽

Vol 568-570 ◽

pp. 359-362

Author(s):

Dong Heng Zhang ◽

Xiu Lin Xu ◽

Xu Dong Guo

Keyword(s):

Visual Feedback ◽

Medical Instrument ◽

Body Movement ◽

Light Signal ◽

The Body ◽

Feedback Signal ◽

Stroke Patients ◽

Positive Role ◽

Movement Function ◽

Command Signals

To improve the muscle function handicap and enhance the body movement function of the stroke patients, a new medical instrument, based on audio-visual feedback, is developed. The designed stimulator regards sound (voice) and light signal (flash lamp) as the command signals. With remind of both voice and visualization signal, trainers can take the initiative to participate in training and try their best to generate a weak electromyographic signal. It provides a new treatment platform for stroke patients, which can play a positive role in the rebuilding of cerebral nerve net, the rehabilitation of body movement function diseases, the protection of brain function and psychological rehabilitation. The real-time monitoring and regulating function for the stimulating current was innovatively achieved. With the above functions, it’s easy for doctors to set up different stimulating intensities for different patients. This stimulator also has advantages of safer noninvasive, easy to carry and advanced human-computer interaction function, all of these make contributions to building up the muscle strength and the rehabilitation of body movement.

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Mechanisms controlling human head stabilization. I. Head-neck dynamics during random rotations in the horizontal plane

Journal of Neurophysiology ◽

10.1152/jn.1995.73.6.2293 ◽

1995 ◽

Vol 73 (6) ◽

pp. 2293-2301 ◽

Cited By ~ 67

Author(s):

F. A. Keshner ◽

B. W. Peterson

Keyword(s):

Visual Feedback ◽

Horizontal Plane ◽

Mental Arithmetic ◽

Human Head ◽

The Body ◽

Myoelectric Activity ◽

Head Tracking ◽

Arithmetic Task ◽

Head Velocity ◽

Head Neck

1. Potential mechanisms for controlling stabilization of the head and neck include voluntary movements, vestibular (VCR) and proprioceptive (CCR) neck reflexes, and system mechanics. In this study we have tested the hypothesis that the relative importance of those mechanisms in producing compensatory actions of the head-neck motor system depends on the frequency of an externally applied perturbation. Angular velocity of the head with respect to the trunk (neck) and myoelectric activity of three neck muscles were recorded in seven seated subjects during pseudorandom rotations of the trunk in the horizontal plane. Subjects were externally perturbed with a random sum-of-sines stimulus at frequencies ranging from 0.185 to 4.11 Hz. Four instructional sets were presented. Voluntary mechanisms were examined by having the subjects actively stabilize the head in the presence of visual feedback as the body was rotated (VS). Visual feedback was then removed, and the subjects attempted to stabilize the head in the dark as the body was rotated (NV). Reflex mechanisms were examined when subjects performed a mental arithmetic task during body rotations in the dark (MA). Finally, subjects performed a voluntary head tracking task while the body was kept stationary (VT). 2. Gains and phases of head velocity indicated good compensation to the stimulus in VS and NV at frequencies < 1 Hz. Gains dropped and phases advanced between 1 and 2 Hz, suggesting interference between neural and mechanical components. Above 3 Hz, the gains of head velocity increased steeply and exceeded unity, suggesting the emergence of mechanical resonance.(ABSTRACT TRUNCATED AT 250 WORDS)

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Can explicit visual feedback of postural sway efface the effects of sensory manipulations on mediolateral balance performance?

Journal of Neurophysiology ◽

10.1152/jn.00103.2014 ◽

2016 ◽

Vol 115 (2) ◽

pp. 907-914 ◽

Cited By ~ 13

Author(s):

L. Eduardo Cofré Lizama ◽

Mirjam Pijnappels ◽

N. Peter Reeves ◽

Sabine M. P. Verschueren ◽

Jaap H. van Dieën

Keyword(s):

Visual Feedback ◽

Repeated Measures ◽

Visual Information ◽

Postural Sway ◽

Center Of Mass ◽

The Body ◽

Body Center ◽

Explicit Feedback ◽

Dominant Frequencies ◽

Visual Conditions

Explicit visual feedback on postural sway is often used in balance assessment and training. However, up-weighting of visual information may mask impairments of other sensory systems. We therefore aimed to determine whether the effects of somatosensory, vestibular, and proprioceptive manipulations on mediolateral balance are reduced by explicit visual feedback on mediolateral sway of the body center of mass and by the presence of visual information. We manipulated sensory inputs of the somatosensory system by transcutaneous electric nerve stimulation on the feet soles (TENS) of the vestibular system by galvanic vestibular stimulation (GVS) and of the proprioceptive system by muscle-tendon vibration (VMS) of hip abductors. The effects of these manipulations on mediolateral sway were compared with a control condition without manipulation under three visual conditions: explicit feedback of sway of the body center of mass (FB), eyes open (EO), and eyes closed (EC). Mediolateral sway was quantified as the sum of energies in the power spectrum and as the energy at the dominant frequencies in each of the manipulation signals. Repeated-measures ANOVAs were used to test effects of each of the sensory manipulations, of visual conditions and their interaction. Overall, sensory manipulations increased body sway compared with the control conditions. Absence of normal visual information had no effect on sway, while explicit feedback reduced sway. Furthermore, interactions of visual information and sensory manipulation were found at specific dominant frequencies for GVS and VMS, with explicit feedback reducing the effects of the manipulations but not effacing these.

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A novel method for investigating the importance of visual feedback on somatosensation and bodily-self perception

Scandinavian Journal of Pain ◽

10.1016/j.sjpain.2017.04.059 ◽

2017 ◽

Vol 16 (1) ◽

pp. 185

Author(s):

Mikkel Thøgersen ◽

John Hansen ◽

Herta Flor ◽

Lars Arendt-Nielsen ◽

Laura Petrini

Keyword(s):

Visual Feedback ◽

Mixed Reality ◽

Visual Input ◽

The Body ◽

Phantom Limb ◽

Hand Position ◽

Self Perception ◽

Left Hand ◽

Novel Method ◽

Relationship Of

AbstractAimsVisual feedback is hypothesized to play an important role in the phantom limb condition. In this study we attempt to create an illusory experimental model of phantom limb wherein this condition is simulated by removing the visual input from the upper limb in a group of intact participants. The aim of the study is to investigate the role of visual feedback on somatosensation, nociception and bodily-self perception.MethodsUsing a novel mixed reality (MR) system, the visual feedback of the left hand is removed in order to visually simulate a left hand amputation on 30 healthy participants (15 females). Using a within-subject design, three conditions are created: visual amputation condition (MR with no visual input); visual condition (MR with normal vision); and a baseline condition (no MR). Thermal detection and nociceptive thresholds using method of limits are measured. Proprioception of the visually amputated hand is investigated by probing the felt hand position on a proximal-distal axis from the body. Using a questionnaire the effects of the missing visual feedback on bodily self is assessed.ResultsThere was a clear drift in proprioception of the left hand in the proximal direction between the control and visual amputation condition (p <0.001). A decrease in cold detection was also significant between the control and visual amputation condition (p < 0.001). Finally, questions on perceptual experiences indicated that the observed proprioceptive retraction of the visually amputated hand was also felt by the participants.ConclusionsMissing visual feedback greatly influences the perception of the visually amputated arm underlining the importance of visual feedback. The observed proprioceptive retraction of the hand resembles the telescoping perceptions often reported by phantom limb patients. The novel method developed for this study, is a new tool to investigate the influence of visual feedback on the relationship of bodily-self and chronic pain.

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Visual self-motion feedback affects the sense of self in virtual reality

10.1101/636944 ◽

2019 ◽

Author(s):

Aubrieann Schettler ◽

Ian Holstead ◽

John Turri ◽

Michael Barnett-Cowan

Keyword(s):

Body Image ◽

Virtual Reality ◽

Visual Feedback ◽

Sense Of Self ◽

Body Schema ◽

The Body ◽

The Self ◽

Top Down ◽

Biological Sex ◽

Self Motion

AbstractWe assessed how self-motion affects the visual representation of the self. We constructed a novel virtual reality experiment that systematically varied an avatar’s motion and also biological sex. Participants were presented with pairs of avatars that visually represented the participant (“self avatar”), or another person (“opposite avatar”). Avatar motion either corresponded with the participant’s motion, or was decoupled from the participant’s motion. The results show that participants identified with i) “self avatars” over “opposite avatars”, ii) avatars moving congruently with self-motion over incongruent motion, and importantly iii) identification with the “opposite avatar” over the “self avatar” when the opposite avatar’s motion was congruent with self-motion. Our results suggest that both self-motion and biological sex are relevant to the body schema and body image and that congruent bottom-up visual feedback of self-motion is particularly important for the sense of self and capable of overriding top-down self-identification factors such as biological sex.

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Grasping Embodiment: Haptic Feedback for Artificial Limbs

Frontiers in Neurorobotics ◽

10.3389/fnbot.2021.662397 ◽

2021 ◽

Vol 15 ◽

Author(s):

Charles H. Moore ◽

Sierra F. Corbin ◽

Riley Mayr ◽

Kevin Shockley ◽

Paula L. Silva ◽

...

Keyword(s):

Visual Feedback ◽

Daily Living ◽

Haptic Feedback ◽

Sense Of Self ◽

The Body ◽

Artificial Limbs ◽

Body Parts ◽

Vibrotactile Feedback ◽

Feedback Type ◽

Upper Limb Prostheses

Upper-limb prostheses are subject to high rates of abandonment. Prosthesis abandonment is related to a reduced sense of embodiment, the sense of self-location, agency, and ownership that humans feel in relation to their bodies and body parts. If a prosthesis does not evoke a sense of embodiment, users are less likely to view them as useful and integrated with their bodies. Currently, visual feedback is the only option for most prosthesis users to account for their augmented activities. However, for activities of daily living, such as grasping actions, haptic feedback is critically important and may improve sense of embodiment. Therefore, we are investigating how converting natural haptic feedback from the prosthetic fingertips into vibrotactile feedback administered to another location on the body may allow participants to experience haptic feedback and if and how this experience affects embodiment. While we found no differences between our experimental manipulations of feedback type, we found evidence that embodiment was not negatively impacted when switching from natural feedback to proximal vibrotactile feedback. Proximal vibrotactile feedback should be further studied and considered when designing prostheses.

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Improving Vision-Based Motor Rehabilitation Interactive Systems for Users with Disabilities Using Mirror Feedback

The Scientific World JOURNAL ◽

10.1155/2014/964576 ◽

2014 ◽

Vol 2014 ◽

pp. 1-9 ◽

Cited By ~ 5

Author(s):

Antoni Jaume-i-Capó ◽

Pau Martínez-Bueso ◽

Biel Moyà-Alcover ◽

Javier Varona

Keyword(s):

Cerebral Palsy ◽

Visual Feedback ◽

User Study ◽

Interactive Systems ◽

The Body ◽

Input Device ◽

Motor Rehabilitation ◽

Feedback Mechanisms ◽

Paired Samples ◽

Within Subjects

Observation is recommended in motor rehabilitation. For this reason, the aim of this study was to experimentally test the feasibility and benefit of including mirror feedback in vision-based rehabilitation systems: we projected the user on the screen. We conducted a user study by using a previously evaluated system that improved the balance and postural control of adults with cerebral palsy. We used a within-subjects design with the two defined feedback conditions (mirrorandno-mirror) with two different groups of users (8with disabilitiesand 32without disabilities) using usability measures (time-to-start(Ts) andtime-to-complete(Tc)). A two-tailed paired samplest-test confirmed that in case of disabilities the mirror feedback facilitated the interaction in vision-based systems for rehabilitation. The measured times were significantly worse in the absence of the user’s own visual feedback (Ts=7.09(P<0.001) andTc=4.48(P<0.005)). In vision-based interaction systems, the input device is the user’s own body; therefore, it makes sense that feedback should be related to the body of the user. In case of disabilities the mirror feedback mechanisms facilitated the interaction in vision-based systems for rehabilitation. Results recommends developers and researchers use this improvement in vision-based motor rehabilitation interactive systems.

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When Does Virtual Embodiment Change Our Minds?

Presence Teleoperators & Virtual Environments ◽

10.1162/pres_a_00263 ◽

2016 ◽

Vol 25 (3) ◽

pp. 222-233 ◽

Cited By ~ 41

Author(s):

Jakki O. Bailey ◽

Jeremy N. Bailenson ◽

Daniel Casasanto

Keyword(s):

Virtual Reality ◽

Visual Feedback ◽

Arm Movements ◽

The Body ◽

Theory Testing ◽

Body Movements ◽

Sensory Experiences ◽

Left And Right ◽

Visual Motor ◽

Sensorimotor Feedback

Can an avatar’s body movements change a person’s perception of good and bad? We discuss virtual embodiment according to theories of embodied cognition (EC), and afferent and sensorimotor correspondences. We present an example study using virtual reality (VR) to test EC theory, testing the effect of altered virtual embodiment on perception. Participants either controlled an avatar whose arm movements were similar to their own or reflected the mirror opposite of their arm movements. We measured their associations of “good” and “bad” with the left and right (i.e., space-valence associations). This study demonstrated how VR could be used to examine the possible ways that systems of the body (e.g., visual, motor) may interact to influence cognition. The implications of this research suggest that visual feedback alone is not enough to alter space-valence associations. Multiple sensory experiences of media (i.e., sensorimotor feedback) may be necessary to influence cognition, not simply visual feedback.

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Bimanual coordination in alcohol-exposed children: Role of the corpus callosum

Journal of the International Neuropsychological Society ◽

10.1017/s1355617704104116 ◽

2004 ◽

Vol 10 (4) ◽

pp. 536-548 ◽

Cited By ~ 36

Author(s):

TRESA M. ROEBUCK-SPENCER ◽

SARAH N. MATTSON ◽

SARAH DEBOARD MARION ◽

WARREN S. BROWN ◽

EDWARD P. RILEY

Keyword(s):

Corpus Callosum ◽

Visual Feedback ◽

Bimanual Coordination ◽

Fetal Alcohol Spectrum Disorders ◽

Task Complexity ◽

Brain Structures ◽

The Body ◽

Group Differences ◽

Interhemispheric Interaction ◽

Significant Group

The corpus callosum (CC) is one of several brain structures affected in children prenatally exposed to alcohol. This structure plays a major role in coordinating motor activity from opposite sides of the body, and deficits in bimanual coordination have been documented in individuals with agenesis of or damage to the CC, particularly when the task is performed without visual feedback. The Bimanual Coordination Test was used to assess speed and accuracy on a task where both hands must coordinate to guide a cursor through angled pathways providing measures of interhemispheric interaction or the ability of the two hemispheres to coordinate activity via the corpus callosum. Twenty-one children with fetal alcohol spectrum disorders (FASD) and 17 non-exposed control children (CON), matched closely in age, sex, and ethnicity were tested. For trials with visual feedback (WV), children with FASD were slower than CON children but were equally accurate. Although statistically significant group differences were not observed on most trials completed without visual feedback (WOV), accuracy of the FASD group on WOV trials was highly variable. Group differences in accuracy on WOV angles approached significance after accounting for performance on the WV angles, and children with FASD were significantly less accurate on an individual angle believed to be particularly sensitive to interhemispheric interaction. These results indicate that children with FASD are slower than CON children but equally accurate on basic visuomotor tasks. However, as task complexity and reliance on interhemispheric interaction increases, children with FASD demonstrate variable and inaccurate performance. Preliminary analyses suggest that inaccurate performance on the bimanual coordination task, and presumably impaired callosal functioning, may be related to the attention and problem solving impairments commonly reported in children with FASD. (JINS, 2004, 10, 536–548.)

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