Distinct adaptation patterns between grip dynamics and arm kinematics when the body is upside-down

2021 ◽  
Vol 125 (3) ◽  
pp. 862-874
Author(s):  
L. Opsomer ◽  
F. Crevecoeur ◽  
J-L. Thonnard ◽  
J. McIntyre ◽  
P. Lefèvre
Keyword(s):  
Reference Frames ◽  
Parabolic Flight ◽  
Arm Movements ◽  
The Body ◽  
Common Mechanism ◽  
Altered Gravity ◽  
Movement Kinematics ◽  
Body Postures ◽  
Arm Kinematics

During rhythmic arm movements performed in an upside-down posture, grip control adapted very quickly, but kinematics adaptation was more progressive. Our results suggest that grip control and movement kinematics planning might operate in different reference frames. Moreover, by comparing our results with previous results from parabolic flight studies, we propose that a common mechanism underlies adaptation to unfamiliar body postures and adaptation to altered gravity.

scholarly journals Effects of Simulated Microgravity and Hypergravity Conditions on Arm Movements in Normogravity

2021 ◽  
Vol 15 ◽  
Author(s):  
Marko Jamšek ◽  
Tjaša Kunavar ◽  
Gunnar Blohm ◽  
Daichi Nozaki ◽  
Charalambos Papaxanthis ◽  
...  
Keyword(s):  
Parabolic Flight ◽  
Arm Movements ◽  
Reaching Movements ◽  
Kinematic Parameters ◽  
Altered Gravity ◽  
Body Experience ◽  
Arm Reaching ◽  
Movement Characteristics ◽  
Environmental Force ◽  
Microgravity Conditions

The human sensorimotor control has evolved in the Earth’s environment where all movement is influenced by the gravitational force. Changes in this environmental force can severely impact the performance of arm movements which can be detrimental in completing certain tasks such as piloting or controlling complex vehicles. For this reason, subjects that are required to perform such tasks undergo extensive training procedures in order to minimize the chances of failure. We investigated whether local gravity simulation of altered gravitational conditions on the arm would lead to changes in kinematic parameters comparable to the full-body experience of microgravity and hypergravity onboard a parabolic flight. To see if this would be a feasible approach for on-ground training of arm reaching movements in altered gravity conditions we developed a robotic device that was able to apply forces at the wrist in order to simulate micro- or hypergravity conditions for the arm while subjects performed pointing movements on a touch screen. We analyzed and compared the results of several kinematic parameters along with muscle activity using this system with data of the same subjects being fully exposed to microgravity and hypergravity conditions on a parabolic flight. Both in our simulation and in-flight, we observed a significant increase in movement durations in microgravity conditions and increased velocities in hypergravity for upward movements. Additionally, we noted a reduced accuracy of pointing both in-flight and in our simulation. These promising results suggest, that locally simulated altered gravity can elicit similar changes in some movement characteristics for arm reaching movements. This could potentially be exploited as a means of developing devices such as exoskeletons to aid in training individuals prior to undertaking tasks in changed gravitational conditions.

Rattlesnake strike behavior: kinematics

1998 ◽  
Vol 201 (6) ◽  
pp. 837-850 ◽  
Author(s):  
K V Kardong ◽  
V L Bels
Keyword(s):  
High Speed ◽  
Predatory Behavior ◽  
The Body ◽  
Body Postures ◽  
Body Segments ◽  
Impact Forces ◽  
Tactile Stimuli ◽  
High Speed Film ◽  
Rodent Prey ◽  
Subsequent Loss

The predatory behavior of rattlesnakes includes many distinctive preparatory phases leading to an extremely rapid strike, during which venom is injected. The rodent prey is then rapidly released, removing the snake's head from retaliation by the prey. The quick action of the venom makes possible the recovery of the dispatched prey during the ensuing poststrike period. The strike is usually completed in less than 0.5 s, placing a premium on an accurate strike that produces no significant errors in fang placement that could result in poor envenomation and subsequent loss of the prey. To clarify the basis for effective strike performance, we examined the basic kinematics of the rapid strike using high-speed film analysis. We scored numerous strike variables. Four major results were obtained. (1) Neurosensory control of the strike is based primarily upon sensory inputs via the eyes and facial pits to launch the strike, and upon tactile stimuli after contact. Correction for errors in targeting occurs not by a change in strike trajectory, but by fang repositioning after the jaws have made contact with the prey. (2) The rattlesnake strike is based upon great versatility and variation in recruitment of body segments and body postures. (3) Forces generated during acceleration of the head are transferred to posterior body sections to decelerate the head before contact with the prey, thereby reducing impact forces upon the snake's jaws. (4) Body acceleration is based on two patterns of body displacement, one in which acute sections of the body open like a gate, the other in which body segments flow around postural curves similar to movements seen during locomotion. There is one major implication of these results: recruitment of body segments, launch postures and kinematic features of the strike may be quite varied from strike to strike, but the overall predatory success of each strike by a rattlesnake is very consistent. <P>

Perception, Expression, and Social Function of Pain: A Human Ethological View

1995 ◽  
Vol 8 (1) ◽  
pp. 31-46 ◽  
Author(s):  
Wulf Schiefenhövel
Keyword(s):  
Evolutionary Biology ◽  
Well Being ◽  
Building Blocks ◽  
Field Work ◽  
The Body ◽  
Human Interaction ◽  
Small Children ◽  
Body Postures ◽  
Culture Independent ◽  
Health And Well Being

The ArgumentPain has important biomedical socioanthropological, semiotic, and other facets. In this contribution pain and the experssion of pain are looked at from the perspective of evolutionary biology, utilizing, among others, cross-cultural data from field work in Melanesia.No other being cares for sick and suffering conspecifics in the way humans do. Notwithstanding aggression and neglect, common in all cultures, human societies can be characterized as empathic, comforting, and promoting the health and well-being of their members. One important stimulus triggering this caring response in others is the expression of pain. The nonverbal channel of communication, particularly certain universal — i.e., culture-independent facial expressions, gestures, and body postures, convey much of the message from the painstricken person to the group.These behaviors signal the person's physical and psychical pain, sadness, grief, and despair in ways very similar to the signs given by infants and small children: the body loses tonus and sinks or drops to the ground, the gestures are those of helplessness. Pain and grief may be so strong that control is lost not only over the body's posture but also over the mind's awareness. In such cases the afflicted person may carry out actions endangering himself or others. In general, these behavior patterns resemble those of infants in situations of distress and danger, and it is not surprising that the response of the members of the group is basically parental: taking care, assisting and consoling.Perceptive and behavioral patterns which developed in the course of avian and mammalian phylogeny to serve the well-being of the young have proven, as was shown by Eibl-Eibesfeldt (1989), to be powerful building blocks for actions in other spheres of human interaction. Love is one such field, the reactions to a conspecific suffering pain is another.

Deviant Treatment of the Body as a Mortuary Ritual

2020 ◽  
pp. 347-360
Author(s):  
Takeshi Ishikawa
Keyword(s):  
Prone Position ◽  
Skeletal Remains ◽  
Decay Process ◽  
The Body ◽  
Body Posture ◽  
Faunal Remains ◽  
Body Postures ◽  
Mortuary Ritual ◽  
The Social ◽  
The Individual

This chapter examines the social meaning of deviant mortuary practices from an osteoarchaeological perspective using skeletal remains from the Middle Jomon Period (ca. 3500–2500 cal BC) found at the Kusakari shell mound. The analyses focus on attributes associated with mortuary body treatments: 1) arrangements of remains, 2) body posture and direction, and 3) the location of burials within the cemetery. Although the usual body postures were dorsal during the period, one individual was laid in a prone position with an unusual body direction compared with other burials. The skeletal arrangement also revealed that the individual had been disarticulated early in the postmortem decay process; however, the remains were located within the usual cemetery area. Based on these results and the extraordinary amount of varied faunal remains in the vicinity, the deviant mortuary treatments appeared to arise from a specific social persona rather than an unusual context of death, such as drowning, suicide, warfare, or other cause.

scholarly journals The gravitational imprint on sensorimotor planning and control

2020 ◽  
Vol 124 (1) ◽  
pp. 4-19 ◽  
Author(s):  
O. White ◽  
J. Gaveau ◽  
L. Bringoux ◽  
F. Crevecoeur
Keyword(s):  
Internal Representation ◽  
The Body ◽  
Altered Gravity ◽  
Partial Adjustment ◽  
Gravitational Forces ◽  
Planning And Control ◽  
Biomechanical Constraints ◽  
And Control ◽  
Future Work ◽  
The Impact

Humans excel at learning complex tasks, and elite performers such as musicians or athletes develop motor skills that defy biomechanical constraints. All actions require the movement of massive bodies. Of particular interest in the process of sensorimotor learning and control is the impact of gravitational forces on the body. Indeed, efficient control and accurate internal representations of the body configuration in space depend on our ability to feel and anticipate the action of gravity. Here we review studies on perception and sensorimotor control in both normal and altered gravity. Behavioral and modeling studies together suggested that the nervous system develops efficient strategies to take advantage of gravitational forces across a wide variety of tasks. However, when the body was exposed to altered gravity, the rate and amount of adaptation exhibited substantial variation from one experiment to another and sometimes led to partial adjustment only. Overall, these results support the hypothesis that the brain uses a multimodal and flexible representation of the effect of gravity on our body and movements. Future work is necessary to better characterize the nature of this internal representation and the extent to which it can adapt to novel contexts.

The body: Postures, gait, proxemics, and haptics.

2016 ◽  
pp. 387-400 ◽  
Author(s):  
David Matsumoto ◽  
Hyisung C. Hwang ◽  
Mark G. Frank
Keyword(s):  
The Body ◽  
Body Postures

The Influence of Visual Information on the Motor Control of Table Tennis Strokes

2012 ◽  
Vol 21 (3) ◽  
pp. 281-294 ◽  
Author(s):  
Stephan Streuber ◽  
Betty J. Mohler ◽  
Heinrich H. Bülthoff ◽  
Stephan de la Rosa
Keyword(s):  
Task Performance ◽  
Visual Information ◽  
Coding Theory ◽  
The Body ◽  
Interaction Partner ◽  
Table Tennis ◽  
Movement Kinematics ◽  
Common Coding ◽  
Radial Error ◽  
Many Sources

Theories of social interaction (i.e., common coding theory) suggest that visual information about the interaction partner is critical for successful interpersonal action coordination. Seeing the interaction partner allows an observer to understand and predict the interaction partner's behavior. However, it is unknown which of the many sources of visual information about an interaction partner (e.g., body, end effectors, and/or interaction objects) are used for action understanding and thus for the control of movements in response to observed actions. We used a novel immersive virtual environment to investigate this further. Specifically, we asked participants to perform table tennis strokes in response to table tennis balls stroked by a virtual table tennis player. We tested the effect of the visibility of the ball, the paddle, and the body of the virtual player on task performance and movement kinematics. Task performance was measured as the minimum distance between the center of the paddle and the center of the ball (radial error). Movement kinematics was measured as variability in the paddle speed of repeatedly executed table tennis strokes (stroke speed variability). We found that radial error was reduced when the ball was visible compared to invisible. However, seeing the body and/or the racket of the virtual players only reduced radial error when the ball was invisible. There was no influence of seeing the ball on stroke speed variability. However, we found that stroke speed variability was reduced when either the body or the paddle of the virtual player was visible. Importantly, the differences in stroke speed variability were largest in the moment when the virtual player hit the ball. This suggests that seeing the virtual player's body or paddle was important for preparing the stroke response. These results demonstrate for the first time that the online control of arm movements is coupled with visual body information about an opponent.

scholarly journals Transcriptional Homeostasis of Oxidative Stress-Related Pathways in Altered Gravity

2018 ◽  
Vol 19 (9) ◽  
pp. 2814 ◽  
Author(s):  
Svantje Tauber ◽  
Swantje Christoffel ◽  
Cora Thiel ◽  
Oliver Ullrich
Keyword(s):  
Oxidative Stress ◽  
Reactive Oxygen Species ◽  
Immune System ◽  
Cellular Response ◽  
Cultured Cells ◽  
Parabolic Flight ◽  
Reactive Oxygen ◽  
Oxygen Species ◽  
Altered Gravity ◽  
Human Immune System

Whereby several types of cultured cells are sensitive to gravity, the immune system belongs to the most affected systems during spaceflight. Since reactive oxygen species/reactive nitrogen species (ROS/RNS) are serving as signals of cellular homeostasis, particularly in the cells of the immune system, we investigated the immediate effect of altered gravity on the transcription of 86 genes involved in reactive oxygen species metabolism, antioxidative systems, and cellular response to oxidative stress, using parabolic flight and suborbital ballistic rocket experiments and microarray analysis. In human myelomonocytic U937 cells, we detected a rapid response of 19.8% of all of the investigated oxidative stress-related transcripts to 1.8 g of hypergravity and 1.1% to microgravity as early as after 20 s. Nearly all (97.2%) of the initially altered transcripts adapted after 75 s of hypergravity (max. 13.5 g), and 100% adapted after 5 min of microgravity. After the almost complete adaptation of initially altered transcripts, a significant second pool of differentially expressed transcripts appeared. In contrast, we detected nearly no response of oxidative stress-related transcripts in human Jurkat T cells to altered gravity. In conclusion, we assume a very well-regulated homeostasis and transcriptional stability of oxidative stress-related pathways in altered gravity in cells of the human immune system.

scholarly journals Contact-free unconstraint respiratory measurements with load cells under the bed in awake healthy volunteers: breath-by-breath comparison with pneumotachography

2019 ◽  
Vol 126 (5) ◽  
pp. 1432-1441 ◽  
Author(s):  
Shiroh Isono ◽  
Natsuko Nozaki-Taguchi ◽  
Makoto Hasegawa ◽  
Shinichiro Kato ◽  
Shinsuke Todoroki ◽  
...  
Keyword(s):  
Respiratory Rate ◽  
Human Subjects ◽  
Load Cell ◽  
The Body ◽  
Phase Changes ◽  
Body Postures ◽  
Load Cells ◽  
Centroid Shift ◽  
Lower Load ◽  
Contact Free

Rate of respiration is a fundamental vital sign. Accuracy and precision of respiratory rate measurements with contact-free load cell sensors under the bed legs were assessed by breath-by-breath comparison with the pneumotachography technique during two different dynamic breathing tasks in 16 awake human adults resting on the bed. The subject voluntarily increased and decreased the respiratory rate between 4 and 16 breaths/min ( n = 8) and 10 and 40 breaths/min ( n = 8) at every 2 breaths in 6 different lying postures such as supine, left lateral, right lateral, and 30, 45, and 60° sitting postures. Reciprocal phase changes of the upper and lower load cell signals accorded with the respiratory phases indicating respiratory-related shifts of the centroid along the long axis of the bed. Bland-Altman analyses revealed 0.66 and 1.59 breaths/min standard deviation differences between the techniques (limits of agreement: −1.22 to 1.36 and −2.96 to 3.30) and 0.07 and 0.17 breaths/min fixed bias differences (accuracy) (confidence interval: 0.04 to 0.10 and 0.12 to 0.22) for the mean respiratory rates of 10.5 ± 3.7 and 24.6 ± 8.9 breaths/min, respectively, regardless of the body postures on the bed. Proportional underestimation by this technique was evident for respiratory rates >40 breaths/min. Sample breath increase up to 10 breaths improved the precision from 1.59 to 0.26 breaths/min. Abnormally faster and slower respirations were accurately detected. We conclude that contact-free unconstraint respiratory rate measurements with load cells under the bed legs are accurate and may serve as a new clinical and investigational tool. NEW & NOTEWORTHY Four load cells placed under the bed legs successfully captured a centroid shift during respiration in human subjects lying on a bed. Breath-by-breath comparison of the breaths covering a wide respiratory rate range by pneumotachography confirmed reliability of the contact-free unconstraint respiratory rate measurements by small standard deviations and biases regardless of body postures. Abnormally faster and slower respirations were accurately detected. This technique should be an asset as a new clinical and investigational tool.

Haptic object recognition is influenced by the orientation of the body relative to gravity

2012 ◽  
Vol 25 (0) ◽  
pp. 122
Author(s):  
Michael Barnett-Cowan ◽  
Jody C. Culham ◽  
Jacqueline C. Snow
Keyword(s):  
Object Recognition ◽  
Character Recognition ◽  
Reference Frames ◽  
Sensory Information ◽  
The Body ◽  
Body Orientation ◽  
Visual Object ◽  
Visual Object Recognition ◽  
Leftward Bias ◽  
Haptic Object

The orientation at which objects are most easily recognized — the perceptual upright (PU) — is influenced by body orientation with respect to gravity. To date, the influence of these cues on object recognition has only been measured within the visual system. Here we investigate whether objects explored through touch alone are similarly influenced by body and gravitational information. Using the Oriented CHAracter Recognition Test (OCHART) adapted for haptics, blindfolded right-handed observers indicated whether the symbol ‘p’ presented in various orientations was the letter ‘p’ or ‘d’ following active touch. The average of ‘p-to-d’ and ‘d-to-p’ transitions was taken as the haptic PU. Sensory information was manipulated by positioning observers in different orientations relative to gravity with the head, body, and hand aligned. Results show that haptic object recognition is equally influenced by body and gravitational references frames, but with a constant leftward bias. This leftward bias in the haptic PU resembles leftward biases reported for visual object recognition. The influence of body orientation and gravity on the haptic PU was well predicted by an equally weighted vectorial sum of the directions indicated by these cues. Our results demonstrate that information from different reference frames influence the perceptual upright in haptic object recognition. Taken together with similar investigations in vision, our findings suggest that reliance on body and gravitational frames of reference helps maintain optimal object recognition. Equally relying on body and gravitational information may facilitate haptic exploration with an upright posture, while compensating for poor vestibular sensitivity when tilted.

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