Visually evoked whole-body turning responses during stepping in place in a virtual environment

SummaryIn the absence of vision, mobility and orientation are challenging. Audio and tactile feedback can be used to guide visually impaired people. In this paper, we present two complementary studies on the use of vibrational cues for hand guidance during the exploration of itineraries on a map, and whole body-guidance in a virtual environment. Concretely, we designed wearable Arduino bracelets integrating a vibratory motor producing multiple patterns of pulses. In a first study, this bracelet was used for guiding the hand along unknown routes on an interactive tactile map. A wizard-of-Oz study with six blindfolded participants showed that tactons, vibrational patterns, may be more efficient than audio cues for indicating directions. In a second study, this bracelet was used by blindfolded participants to navigate in a virtual environment. The results presented here show that it is possible to significantly decrease travel distance with vibrational cues. To sum up, these preliminary but complementary studies suggest the interest of vibrational feedback in assistive technology for mobility and orientation for blind people.

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Three-dimensional whole body of virtual character animation for its behavior in a virtual environment using H-Anim and inverse kinematics

Storytelling in Medicine ◽

10.1109/cgi.2004.1309226 ◽

2004 ◽

Cited By ~ 2

Author(s):

A. Ortiz ◽

D. Oyarzun ◽

I. Aizpurua ◽

J. Posada

Keyword(s):

Virtual Environment ◽

Inverse Kinematics ◽

Three Dimensional ◽

Character Animation ◽

Whole Body ◽

Virtual Character

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Preprint: Embodiment of approach-avoidance behavior

10.31219/osf.io/2rftv ◽

2019 ◽

Cited By ~ 1

Author(s):

Andreas B Eder ◽

Anand Krishna ◽

Albrecht Sebald ◽

Wilfried Kunde

Keyword(s):

Virtual Reality ◽

Virtual Environment ◽

Avoidance Behavior ◽

Whole Body ◽

Body Movements ◽

Avoidance Motivation ◽

Aversive Stimuli ◽

Approach Avoidance

Previous studies showed that humans can flexibly reconfigure manual reactions to motivational stimuli in order to produce compatible changes in visual environments (i.e., approach appetitive and avoid aversive stimuli). Using a virtual reality headset, we examined whether analogous flexibility is observed with whole-body movements in forward and backward directions that produced (non-)corresponding visual movements in a virtual environment. Two experiments showed that forward movements were initiated faster in response to a (pleasant) flower and backward movements in response to an (unpleasant) spider, even when the movements resulted in reverse visual motions towards the spider and away from the flower. In contrast, visual motions were more important when these motions were controlled manually and after strategic preparation of producing body steps. Overall, results suggest that there is a highly overlearned connection between locomotion and approach/avoidance that is difficult to override. Implications in regard to the embodiment of approach-avoidance motivation are discussed.

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Podokinetic After-Rotation Is Transiently Enhanced or Reversed by Unilateral Axial Muscle Proprioceptive Stimulation

Neural Plasticity ◽

10.1155/2019/7129279 ◽

2019 ◽

Vol 2019 ◽

pp. 1-11 ◽

Cited By ~ 1

Author(s):

Stefania Sozzi ◽

Antonio Nardone ◽

Oscar Crisafulli ◽

Marco Schieppati

Keyword(s):

Angular Velocity ◽

Rotation Velocity ◽

Whole Body ◽

Common Mechanism ◽

Muscle Vibration ◽

Body Rotation ◽

Lumbar Level ◽

Axial Muscle ◽

Paravertebral Muscles ◽

Stepping In Place

Unilateral axial muscle vibration, eliciting a proprioceptive volley, is known to incite steering behavior. Whole-body rotation while stepping in place also occurs as an after-effect of stepping on a circular treadmill (podokinetic after-rotation, PKAR). Here, we tested the hypothesis that PKAR is modulated by axial muscle vibration. If both phenomena operate through a common pathway, enhancement or cancellation of body rotation would occur depending on the stimulated side when vibration is administered concurrently with PKAR. Seventeen subjects participated in the study. In one session, subjects stepped in place eyes open on the center of a platform that rotated counterclockwise 60°/s for 10 min. When the platform stopped, subjects continued stepping in place blindfolded. In other session, a vibratory stimulus (100 Hz, 2 min) was administered to right or left paravertebral muscles at lumbar level at two intervals during the PKAR. We computed angular body velocity and foot step angles from markers fixed to shoulders and feet. During PKAR, all subjects rotated clockwise. Decreased angular velocity was induced by right vibration. Conversely, when vibration was administered to the left, clockwise rotation velocity increased. The combined effect on body rotation depended on the time at which vibration was administered during PKAR. Under all conditions, foot step angle was coherent with shoulder angular velocity. PKAR results from continuous asymmetric input from the muscles producing leg rotation, while axial muscle vibration elicits a proprioceptive asymmetric input. Both conditioning procedures appear to produce their effects through a common mechanism. We suggest that both stimulations would affect our straight ahead by combining their effects in an algebraic mode.

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Assessing Automatic Approach-Avoidance Behavior in an Immersive Virtual Environment

Frontiers in Virtual Reality ◽

10.3389/frvir.2021.761142 ◽

2021 ◽

Vol 2 ◽

Author(s):

Juliane Degner ◽

Lea Steep ◽

Susanne Schmidt ◽

Frank Steinicke

Keyword(s):

Virtual Environment ◽

Avoidance Behavior ◽

Body Movement ◽

Whole Body ◽

Approach And Avoidance ◽

Stimulus Response ◽

Immersive Virtual Environment ◽

Behavioral Tendencies ◽

Approach Avoidance ◽

And Behavior

The use of virtual reality (VR) promises enormous potential for studying human behavior. While approach and avoidance tendencies have been explored in various areas of basic and applied psychology, such as attitude and emotion research, basic learning psychology, and behavior therapy, they have rarely been studied in VR. One major focus of this research is to understand the psychological mechanisms underlying automatic behavioral tendencies towards and away from positively or negatively evaluated stimuli. We implemented a whole-body movement stimulus-response compatibility task to explore approach-avoidance behavior in an immersive virtual environment. We chose attitudinal stimuli—spiders and butterflies—on which people widely agree in their general evaluations (in that people evaluate spiders negatively and butterflies positively), while there is still substantial inter-individual variance (i. e., the intensity in which people dislike spiders or like butterflies). We implemented two parallel approach-avoidance tasks, one in VR, one desktop-based. Both tasks revealed the expected compatibility effects that were positively intercorrelated. Interestingly, however, the compatibility effect in the VR measure was unrelated to participants’ self-reported fear of spiders and stimulus evaluations. These results raise important implications about the usage of VR to study automatic behavioral tendencies.

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Neck Muscle Vibration and Spatial Orientation During Stepping in Place in Humans

Journal of Neurophysiology ◽

10.1152/jn.00198.2002 ◽

2002 ◽

Vol 88 (5) ◽

pp. 2232-2241 ◽

Cited By ~ 90

Author(s):

Marco Bove ◽

Gregoire Courtine ◽

Marco Schieppati

Keyword(s):

The Body ◽

Body Orientation ◽

Body Tilt ◽

Whole Body ◽

Neck Muscle ◽

Body Rotation ◽

Erect Posture ◽

Proprioceptive Input ◽

Neck Muscle Vibration ◽

Stepping In Place

Unilateral long-lasting vibration was applied to the sternomastoid muscle to assess the influence of asymmetric neck proprioceptive input on body orientation during stepping-in-place. Blindfolded subjects performed 3 sequences of 3 trials, each lasting 60 s: control, vibration applied during stepping (VDS), and vibration applied before stepping (VBS). VDS caused clear-cut whole body rotation toward the side opposite to vibration. The body rotated around a vertical axis placed at about arm's length from the body. The rotation did not begin immediately on switching on the vibrator. The delay varied from subject to subject from a few seconds to about 10 s. Once initiated, the angular velocity of rotation was remarkably constant (about 1°/s). In VBS, at the beginning of stepping, subjects rotated for a while as if their neck were still vibrated. At a variable delay, the direction of rotation reversed, and the effects were opposite to those observed during VDS. Under no condition did head rotation, head roll, or lateral body tilt accompany rotation. The results confirm and extend the notion that the neck proprioceptive input plays a major role in body orientation during locomotion. The body rotation does not seem to depend on the same mechanisms that modify the erect posture; rather, the asymmetric neck input would seem to modify the egocentric body-centered coordinate system.

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Case study: CAREN (computer assisted rehabilitation environment): A novel way to improve shoe efficacy

Prosthetics and Orthotics International ◽

10.1080/03093640308726673 ◽

2003 ◽

Vol 27 (2) ◽

pp. 158-162 ◽

Cited By ~ 5

Author(s):

I.J.M. De Groot ◽

O. Even Zohar ◽

R. Haspels ◽

H. Van Keeken ◽

E. Otten

Keyword(s):

Virtual Environment ◽

Natural Environment ◽

Body Movement ◽

Movement Analysis ◽

Technical System ◽

Whole Body ◽

Computer Assisted ◽

Total Body ◽

Made In

A new technical system, CAREN (computer assisted rehabilitation environment), is described, which makes it possible to do a total body movement analysis in a virtual environment. The virtual environment is reproducible and as close to natural environment as possible. In a case study it proved possible with this system to test different shoes and get insight in the movement problems. The importance of whole body analysis is demonstrated in this case study. The adjustments made in the shoes could be tested for their efficacy.

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Influence of Leg Muscle Vibration on Human Walking

Journal of Neurophysiology ◽

10.1152/jn.2000.84.4.1737 ◽

2000 ◽

Vol 84 (4) ◽

pp. 1737-1747 ◽

Cited By ~ 85

Author(s):

Y. P. Ivanenko ◽

R. Grasso ◽

F. Lacquaniti

Keyword(s):

Stance Phase ◽

Walking Speed ◽

Triceps Surae ◽

Body Tilt ◽

Whole Body ◽

Muscle Vibration ◽

Eyes Closed ◽

Thigh Muscles ◽

Leg Muscle ◽

Stepping In Place

We studied the effect of vibratory stimulation of different leg muscles [bilateral quadriceps (Q), hamstring (HS) muscles, triceps surae (TS), and tibialis anterior (TA)] in seven normal subjects during 1) quiet standing, 2) stepping in place movements, and 3) walking on the treadmill. The experiments were performed in a dimly illuminated room, and the subjects were given the instruction not to resist the applied perturbation. In one condition the velocity of the treadmill was controlled by a feedback from the subject's current position. In normal standing, TA vibration elicited a prominent forward body tilt, whereas HS and TS vibration elicited backward trunk or whole body inclination, respectively. Q vibration had little effect. During stepping in place, continuous HS vibration produced an involuntary forward stepping at about 0.3 m s− 1 without modifying the stepping frequency. When the subjects (with eyes closed) kept a hand contact with an external still object, they did not move forward but perceived an illusory forward leg flexion relative to the trunk. Q, TS, and TA vibration did not cause any systematic body translation nor illusory changes in body configuration. In treadmill locomotion, HS vibration produced an involuntary steplike increase of walking speed (by 0.1–0.6 m·s− 1). Continuous vibration elicited larger speed increments than phasic stimulation during swing or stance phase. For phasic stimulation, HS vibration tended to be more effective when applied during swing than during stance phase. Q, TA, and TS vibration had little if any effect. Vibration of thigh muscles altered the walking speed depending on the direction of progression. During backward locomotion, the walking speed tended to decrease after HS vibration, whereas it significantly increased after Q vibration. Thus the influence of leg muscle vibration on stepping in place and locomotion differed significantly from that on normal posture. We suggest that the proprioceptive input from thigh muscles may convey information about the velocity of the foot movement relative to the trunk.

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Occurrence and biogeographic significance of Heliaster (Echinodermata: Asteroidea) from the Pliocene of southwest Florida

Journal of Paleontology ◽

10.1017/s0022336000058960 ◽

1988 ◽

Vol 62 (01) ◽

pp. 126-132 ◽

Cited By ~ 8

Author(s):

Douglas S. Jones ◽

Roger W. Portell

Keyword(s):

Central American ◽

Eastern Pacific ◽

Whole Body ◽

Marine Fauna ◽

Western Atlantic ◽

Southwest Florida ◽

Extant Species ◽

Geologic Record ◽

Central American Isthmus

Whole body asteroid fossils are rare in the geologic record and previously unreported from the Cenozoic of Florida. However, specimens of the extant species,Heliaster microbrachiusXantus, were recently discovered in upper Pliocene deposits. This marks the first reported fossil occurrence of the monogeneric Heliasteridae, a group today confined to the eastern Pacific. This discovery provides further non-molluscan evidence of the close similarities between the Neogene marine fauna of Florida and the modern fauna of the eastern Pacific. The extinction of the heliasters in the western Atlantic is consistent with the pattern of many other marine groups in the region which suffered impoverishment following uplift of the Central American isthmus.

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