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Background: Little is known about the effectiveness of instructors when presenting content in videos alone. In recent years, researchers have increasingly begun to explore the effects of instructors' social cues (e.g., eye gaze, body orientation, etc.) on learning. However, previous studies exploring the effects of eye gaze have confounded the role of body orientation, while studies exploring body orientation have confounded the role of eye gaze. Objectives: To explore the role of direct gaze and body orientation in learning with instructional videos, absent an instructional screen, in a less confounded manner. Methods: A total of 63 subjects were presented select concepts regarding schizophrenia. Eye‐tracking technology combined with current theories of parasocial interaction and social agency was used to explore different social cues that affect learning performance. Students were randomly assigned to one of three experimental conditions: frontal body + direct gaze group (FD group), frontal body + no direct gaze group (FND group), and lateral body + no direct gaze group (LND group). Result and Conclusions: Direct gaze facilitated students' immediate retention and transfer scores, reduced learners' extraneous cognitive load, and guided students' attention to the instructor. However, counter to our expectations, parasocial interaction did not affect social cues. Implications: In both online and offline classes, instruction is expected to be enhanced by focusing on the camera to the extent possible, particularly when instructional screens are absent. Lay Description: What is already known about this topic: In recent years, how instructors' social cues (eye gaze, body orientation, gestures, etc.) can improve video learning has aroused widespread concern.Instructors' eye gaze and body orientation can increase society and improve learning in the online learning environment.The empirical research confounds the role of eye gaze and body orientation on video learning when only the instructors are present. What this paper adds: When only the instructor is present in the video, instructor's direct gaze can foster learner's learning outcome in the instructional video.When only the instructor is present in the video, instructor's direct gaze can draw the learner's attention to the instructor's face.When only the instructor is present in the video, instructor's direct gaze can reduce learner's extraneous cognitive load. Implications for practice and/or policy: In online teaching, educators should consider looking at the camera as much as possible, especially when there are no instructional screens. [ABSTRACT FROM AUTHOR]

The text describes the method of script drama work in therapy, counselling and supervision. The method combines TA concepts such as decontamination, work on impasses, deconfusion and the body-based method of Al Pesso and Diane Boyden Pesso. It shows how microtracking and special constellations are used to understand and appreciate the client's inner system and supplement it with new, corrective experiences. The integrating adult is addressed and strengthened as a central instance on the client's side. Case studies are used to demonstrate how beliefs and assumptions can become evident in a body-oriented way in the here and now and how their inhibiting effects are neutralized. [ABSTRACT FROM AUTHOR]

Domestic chicks (Gallus gallus domesticus) have been widely used as a model to study the motion cues that allow visually naïve organisms to detect animate agents shortly after hatching/birth. Our previous work has shown that chicks prefer to approach agents whose main body axis and motion direction are aligned (a feature typical of creatures whose motion is constrained by a bilaterally symmetric body plan). However, it has never been investigated whether chicks are also sensitive to the fact that an agent maintains a stable front–back body orientation in motion (i.e. consistency in which end is leading and which trailing). This is another feature typical of bilateria, which is also associated with the detection of animate agents in humans. The aim of the present study was to fill this gap. Contrary to our initial expectations, after testing 300 chicks across 3 experimental conditions, we found a recurrent preference for the agent which did not maintain a stable front–back body orientation. Since this preference was limited to female chicks, the results are discussed also in relation to sex differences in the social behaviour of this model. Overall, we show for the first time that chicks can discriminate agents based on the stability of their front–back orientation. The unexpected direction of the effect could reflect a preference for agents' whose behaviour is less predictable. Chicks may prefer agents with greater behavioural variability, a trait which has been associated with animate agents, or have a tendency to explore agents performing "odd behaviours". [ABSTRACT FROM AUTHOR]

The integration of vestibular, visual and body cues is a fundamental process in the perception of self-motion and is commonly experienced in an upright posture. However, when the body is tilted in an off-vertical orientation these signals are no longer aligned relative to the influence of gravity. In this study, the perceived timing of visual motion was examined in the presence of sensory conflict introduced by manipulating the orientation of the body, generating a mismatch between body and vestibular cues due to gravity and creating an ambiguous vestibular signal of either head tilt or translation. In a series of temporal-order judgment tasks, participants reported the perceived onset of a visual scene simulating rotation around the yaw axis presented in virtual reality with a paired auditory tone while in an upright, supine and side-recumbent body position. The results revealed that the perceived onset of visual motion was further delayed from zero (i.e., true simultaneity between visual onset and a reference auditory tone) by approximately an additional 30 ms when viewed in a supine or side-recumbent orientation compared to an upright posture. There were also no significant differences in the timing estimates of the visual motion between all the non-upright orientations. This indicates that the perceived timing of visual motion is negatively impacted by the presence of conflict in the vestibular and body signals due to the direction of gravity and body orientation, even when the mismatch is not in the direct plane of the axis of rotation. [ABSTRACT FROM AUTHOR]

A bistable image admits two possible interpretations, so that the observer can recognize the two percepts, but never at the same time. The alternations between percepts are called "perceptual reversals". When the observer's position is different from the upright position, the ability to make perceptual alternations may be impaired. Besides, the recognition of the percepts of a bistable image can be a complex reaction time visual task, if it involves recognizing two different conceptual units, added to the fact of having to make a subsequent report. A visual task was performed by 88 people in order to establish whether the perception of Boring's bistable image My girlfriend or my mother-in-law is associated with areas that condition its interpretation. It was assumed that decoding the image and reporting the perceived percept implied a complex reaction time. The task itself was done in front of a fixed 120 Hz eye-tracker, in two opposite body positions. Analyses were made reviewing the association of the percepts with bottom-up modulation areas of the image, and considering ocular fixations made 200 and 250 milliseconds before the time of the report. The records of these fixations were obtained so as to establish which of the two reaction times (200 ms or 250 ms) was involved in the bottom-up modulation process from the moment of ocular fixation to the reports given by the participants. It was concluded that perceptual reversals decrease significantly when head idiotropic axis points in the gravity vector direction, in comparison to the upright position. Likewise, associations between visual percepts and bottom-up modulating areas of the image were found when analyses were done by considering ocular fixations made 250 ms before the moment of the report. Interpreting Boring's bistable image implies a complex visual task in accordance with the results obtained. [ABSTRACT FROM AUTHOR]

We studied the characteristics of the marking behavior of Asiatic black bears (Ursus thibetanus) at rub trees. We recorded the tree-marking (tree-rubbing and bark-scratching) and associated (stomping) behaviors in Japan between 2010 and 2015 using automatic cameras and compared the results with those from previous studies on other bear species. We recorded 22 visits to trees by ≥6 different individuals. During these visits, there were no differences in the frequency or duration between the 3 body orientations of back rubbing, front rubbing, and body-side rubbing, which differs from the findings for other bear species. However, bipedal standing was the most common posture, as observed in other species. We also analyzed the order of tree-marking actions. For a better understanding of the Asiatic black bear's marking behavior, further examples of marking behavior and anatomical studies of secretory glands are needed. [ABSTRACT FROM AUTHOR]

• After stroke, body orientation improved with time in most individuals. • However, half of individuals with lateropulsion were still not upright at 3 months. • Lateropulsion attenuation was not slower in individuals with severe forms. • Balance and gait recovery was possible without improvement of body orientation. • Lateropulsion attenuation enhanced balance and gait recovery during the same period. Lateropulsion is a deficit in body orientation with respect to gravity, frequent after stroke. Although it is a primary factor affecting mobility, the impact of its attenuation on balance and gait recovery has never been investigated. Moreover, most studies on the lateropulsion time-course focus on severe forms suspected to have a poor recovery, which is not proven. To investigate lateropulsion attenuation and test 2 hypotheses: 1) lateropulsion attenuation greatly contributes to balance and gait recovery and 2) severe forms of lateropulsion recover slower than moderate forms. This longitudinal study involved individuals included in the Determinants of Balance Recovery After Stroke (DOBRAS) cohort, after a first-ever hemispheric stroke, with data collected on day 30 (D30), D60 and D90 post-stroke. Body orientation with respect to gravity was assessed using the Scale for Contraversive Pushing (both scores and severity grouping), in parallel with balance (Postural Assessment Scale for Stroke) and gait (modified Fugl-Meyer Gait Assessment). Among the 106 eligible individuals (mean age 66.5 [SD 9.7] years), on D30, 43 (41%) were considered upright and 63 (59%) showed lateropulsion: 30 (28%) moderate and 33 (31%) severe. Most individuals with lateropulsion (73%) improved their body orientation, progressing from severe to moderate lateropulsion, or becoming upright. However, half were still not upright on D90. The improvement in body orientation had a large impact on mobility, especially in individuals with severe lateropulsion, in whom it explained about 50% of balance and gait recovery between D30 and D60, then 20% (D60-D90). For moderate lateropulsion, its attenuation explained about 20% of balance and gait recovery until D90. Lateropulsion attenuation was not slower in individuals with severe forms. Lateropulsion attenuation enhances balance and gait recovery in individuals after stroke suggesting that specific rehabilitation of body orientation with respect to gravity might help to recover mobility. NCT03203109 [ABSTRACT FROM AUTHOR]

Purpose: Spontaneous postural sway during quiet standing has been considered a simple output error of postural control. However, as postural sway and inherent body orientation evoke compensatory activity of the plantar flexors, they might contribute to blood circulation under gravitational stress via the muscle pump. Hence, the present study employed an external support device to attenuate the plantar flexor activity in supported standing (SS), to experimentally identify its physiological impact on blood circulation. Methods: Eight healthy young subjects performed two 5-min quiet standing trials (i.e., normal standing (NS) and SS), and the beat-to-beat interval (RRI) and blood pressure (BP) were compared between trials. We confirmed that postural sway and corresponding plantar flexor activity, quantified by the anteroposterior displacement of the foot center of pressure and lower back position with respect to the wall, and by the amplitude of electromyography and mechanomyography, respectively, were attenuated in SS, while mean body orientation angle and relative position of the BP sensor were comparable to NS. Results: The 5-min averages of diastolic BP and mean arterial pressure during SS were significantly higher than during NS, while RRI and systolic BP did not change. These could be interpreted as an increase in peripheral vascular resistance; meanwhile, in NS, this effect was replaced by the muscle pump of the plantar flexors. Conclusion: The muscle contractions related to spontaneous postural sway and body orientation produce substantial physiological impact on blood circulation during quiet standing. [ABSTRACT FROM AUTHOR]

Introduction: Multisensory audiovisual semantic congruency is the process by which visual information is perceived as integrated to auditory stimuli, because both coincide in terms of simultaneity and semantic correspondence. This study was aimed at establishing whether visual percepts, which semantically correspond to auditory stimuli, are associated with ocular fixations in modulating bottom-up areas while keeping a body posture alignment between the up-direction and the idiotropic axes, as well as in another orientation corresponding to a vectorial opposition between the up-direction and the head idiotropic axis. Method: Two groups (one for each position) were selected from a sample of 88 people. A bistable image was presented on a screen of a fixed 120 Hz eye-tracker device, providing background auditory stimuli so as to establish semantic congruencies and their relations to ocular fixations. Results: It was found that audiovisual semantic congruency is associated with fixations when idiotropic vectors are aligned with the up direction. Fixations manifested in bottom-up modulating areas are not associated with multisensory audiovisual semantic congruency when the head idiotropic vector is parallel with the gravity vector. Eye fixations decrease significantly if the head idiotropic axis is aligned with the gravity vector. Conclusion: It is concluded that body position can affect visual perceptual processes involved in the occurrence of semantic congruency. [ABSTRACT FROM AUTHOR]

Body orientation of gesture entails social‐communicative intention, and may thus influence how gestures are perceived and comprehended together with auditory speech during face‐to‐face communication. To date, despite the emergence of neuroscientific literature on the role of body orientation on hand action perception, limited studies have directly investigated the role of body orientation in the interaction between gesture and language. To address this research question, we carried out an electroencephalography (EEG) experiment presenting to participants (n = 21) videos of frontal and lateral communicative hand gestures of 5 s (e.g., raising a hand), followed by visually presented sentences that are either congruent or incongruent with the gesture (e.g., "the mountain is high/low..."). Participants underwent a semantic probe task, judging whether a target word is related or unrelated to the gesture‐sentence event. EEG results suggest that, during the perception phase of handgestures, while both frontal and lateral gestures elicited a power decrease in both the alpha (8–12 Hz) and the beta (16–24 Hz) bands, lateral versus frontal gestures elicited reduced power decrease in the beta band, source‐located to the medial prefrontal cortex. For sentence comprehension, at the critical word whose meaning is congruent/incongruent with the gesture prime, frontal gestures elicited an N400 effect for gesture‐sentence incongruency. More importantly, this incongruency effect was significantly reduced for lateral gestures. These findings suggest that body orientation plays an important role in gesture perception, and that its inferred social‐communicative intention may influence gesture‐language interaction at semantic level. [ABSTRACT FROM AUTHOR]

The feeling of being addressed is the first step in a complex processing stream enabling successful social communication. Social impairments are a relevant characteristic of patients with major depressive disorder (MDD). Here, we investigated a mechanism which—if impaired—might contribute to withdrawal or isolation in MDD, namely, the neural processing of social cues such as body orientation and gesture. During funtional magnetic resonance imaging (fMRI) data acquisition, 33 patients with MDD and 43 healthy control subjects watched video clips of a speaking actor: one version with a gesture accompanying the speech and one without gesture. Videos were filmed simultaneously from two different viewpoints: one with the actor facing the viewer head‐on (frontal) and one side‐view (lateral). After every clip, the participants were instructed to evaluate whether they felt addressed or not. Despite overall comparable addressment ratings and a large overlap in activation patterns in MDD and healthy subjects for gesture processing, the anterior cingulate cortex, bilateral superior/middle frontal cortex, and right angular gyrus were more strongly activated in patients than in healthy subjects for the frontal conditions. Our analyses revealed that patients showed specifically higher activation than healthy subjects for the frontal condition without gesture in regions including the posterior cingulate cortex, left prefrontal cortex, and the left hippocampus. We conclude that MDD patients can recognize and interpret social cues such as gesture or body orientation; however, they seem to require more neural resources. This additional effort might affect successful communication and contribute to social isolation in MDD. [ABSTRACT FROM AUTHOR]

Horizontal force-velocity (F-V) profiling is a strategy to assess athletes' individual performance capabilities during sprinting. This study investigated the acute changes in F-V profiles during sprinting of fourteen collegiate male sprinters with a mean 100-m sprint time of 11.40 ± 0.39 s, from a split-stance starting position. The subjects sprinted 30-m with, and without, wearable resistance (WR) equivalent to 2% body mass, attached to their forearms. Sprinting time at 5, 10, 20, and 30-m was assessed using laser technology. External horizontal F-V relationships were calculated via velocity-time signals. Maximal theoretical velocity (V0), theoretical relative and absolute horizontal force (F0), and horizontal power (Pmax) were determined from the F-V relationship. Paired t-tests were used to determine statistical differences (p ≤ 0.05) in variables across conditions with Cohen's d as effect sizes (ES) calculated to assess practical changes. Sprint times at 10-m and beyond were significantly increased (1.9–3.3%, p 0.01–0.03, ES 0.46–0.60) with WR compared to unloaded sprinting. The only significant change in F-V with the WR condition was found in relative Pmaxsystem (−6.1%, p 0.01, ES 0.66). A small decrease was reported in V0 (−1.0%, p 0.11, ES 0.27), with small to medium ES decreases reported in F0 (−4.8% to −6.1%, p 0.07–0.21, ES 0.25-0.51) and Pmax (−4.3% to −4.6%, p 0.06–0.08, ES 0.32–0.45). The greater changes to F0 and Pmax suggest that forearm WR may be a possible training tool for athletes who wish to focus on force and power adaptation during sprint acceleration from a standing start. [ABSTRACT FROM AUTHOR]

The analysis of customer pose draws more and more attention of retailers and researchers, because this information can reveal the customer habits and the customer interest level to the merchandise. In the retail store environment, customers’ poses are highly related to their body orientations. For example, when a customer is picking an item from merchandise shelf, he or she must face to the shelf. On the other hand, if the customer body orientation is parallel to the shelf, this customer is probably just walking through. Considering this fact, we propose a customer pose estimation system using orientational spatio-temporal deep neural network from surveillance camera. This system first generates the initial joint heatmaps using a fully convolutional network. Based on these heatmaps, we propose a set of novel orientational message-passing layers to fine-tune joint heatmaps by introducing the body orientation information into the conventional message-passing layers. In addition, we apply a bi-directional recurrent neural network on top of the system to improve the estimation accuracy by considering both forward and backward image sequences. Therefore, in this system, the global body orientation, local joint connections, and temporal pose continuity are integrally considered. At last, we conduct a series of comparison experiments to show the effectiveness of our system. [ABSTRACT FROM AUTHOR]

In this work, we try to reproduce empirical results concerning the behaviour of a human crowd in a cross-flow using a hierarchy of models, which differ in the details of the body shape (using a disk-shaped body vs a more realistic elliptical shape) and in how collision avoiding is performed (using only information regarding "centre of mass" distance and velocity, or actually introducing body shape information). We verified that the most detailed model (i.e., using body shape information and an elliptical body) outperforms in a significant way the simplest one (using only centre of mass distance and velocity, and disk-shaped bodies). Furthermore, we observed that if elliptical bodies are introduced without introducing such information in collision avoidance, the performance of the model is relatively poor. Nevertheless, the difference between the different models is relevant only in describing the "tails" of the observable distributions, suggesting that the more complex models could be of practical use only in the description of high density settings. Although we did not calibrate our model in order to reproduce "stripe formation" self-organising patterns observed in the crossing area, we verified that they emerge naturally in all models. • We use numerical models to reproduce the dynamics of a pedestrian cross-flow. • We use a hierarchy of models with growing complexity. • We analyse a few macroscopic and microscopic observables, including body orientation. • We focus on aspects of the models necessary to reproduce the observed dynamics. [ABSTRACT FROM AUTHOR]

In this work we investigate the behaviour of a human crowd in a cross-flow by analysing the results of a set of controlled experiments in which subjects were divided into two groups, organised in such a way to explore different density settings, and asked to walk through the crossing area. We study the results of the experiment by defining and investigating a few macroscopic and microscopic observables. Along with analysing traditional indicators such as density and velocity, whose dynamics was, to the extent of our knowledge, poorly understood for this setting, we pay particular attention to walking and body orientation, studying how these microscopic observables are influenced by density. Furthermore, we report a preliminary but quantitative analysis on the emergence of self-organising patterns (stripes) in the crossing area, a phenomenon that had been previously qualitatively reported for human crowds, and reproduced in models, but whose quantitative analysis with respect to density conditions is, again according to our knowledge, a novel contribution. • We perform controlled experiments to study crowd dynamics in a crossing flow. • We study such dynamics by introducing a few macroscopic and microscopic observables. • We focus in particular on body orientation and its deviation from velocity direction. [ABSTRACT FROM AUTHOR]

Although the interpreter's function in interaction has attracted significant interest in the literature, the focus is often restricted to verbal interaction alone. This paper introduces an analytical framework, based on Goffman's construct of role, to examine how participants' actions: (i) carry communicative meaning that complements their use of language; ii) are interdependent with those of other participants. The analysis also takes into account the normative frameworks which, to a certain extent, shape the interpreter's and the doctor's actions. Transcribed excerpts of two authentic medical consultations are examined, along with video stills. The recordings, with interpreting between Dutch and Russian, were made at a Belgian hospital; informed consent and ethical approval were obtained. It is shown that interpreters' use of non-verbal resources can favour the patient's inclusion in interaction when s/he is bypassed by the doctor, possibly interested in involving only the interpreter and in leaving little, if any, opportunity for the patient's voice to be heard. [ABSTRACT FROM AUTHOR]

Orientation with respect to the sun has been observed in a wide range of species and has generally been interpreted in terms of thermoregulation and/or ultraviolet (UV) protection. For countershaded animals, orientation with respect to the sun may also result from the pressure to exploit the gradient of coloration optimally to enhance crypsis., Here, we use computational modelling to predict the optimal countershading pattern for an oriented body. We assess how camouflage performance declines as orientation varies using a computational model that incorporates realistic lighting environments., Once an optimal countershading pattern for crypsis has been chosen, we determine separately how UV protection/irradiation and solar thermal inflow fluctuate with orientation., We show that body orientations that could optimally use countershading to enhance crypsis are very similar to those that allow optimal solar heat inflow and UV protection., Our findings suggest that crypsis has been overlooked as a selective pressure on orientation and that new experiments should be designed to tease apart the respective roles of these different selective pressures. We propose potential experiments that could achieve this. [ABSTRACT FROM AUTHOR]

During face-to-face communication, body orientation and coverbal gestures influence how information is conveyed. The neural pathways underpinning the comprehension of such nonverbal social cues in everyday interaction are to some part still unknown. During fMRI data acquisition, 37 participants were presented with video clips showing an actor speaking short sentences. The actor produced speech-associated iconic gestures (IC) or no gestures (NG) while he was visible either from an egocentric (ego) or from an allocentric (allo) position. Participants were asked to indicate via button press whether they felt addressed or not. We found a significant interaction of body orientation and gesture in addressment evaluations, indicating that participants evaluated IC-ego conditions as most addressing. The anterior cingulate cortex (ACC) and left fusiform gyrus were stronger activated for egocentric versus allocentric actor position in gesture context. Activation increase in the ACC for IC-ego>IC-allo further correlated positively with increased addressment ratings in the egocentric gesture condition. Gesture-related activation increase in the supplementary motor area, left inferior frontal gyrus and right insula correlated positively with gesture-related increase of addressment evaluations in the egocentric context. Results indicate that gesture use and body-orientation contribute to the feeling of being addressed and together influence neural processing in brain regions involved in motor simulation, empathy and mentalizing. Hum Brain Mapp 36:1925-1936, 2015. © 2015 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Highlights: [•] We examine infants’ gaze shifts using eye-tracking technique. [•] We present images with two faces in a face-to-face or back-to-back configuration with open or closed eyes. [•] From 9 months onwards, infants rely on body orientation (face-to-face effect) to detect others’ social interactions. [ABSTRACT FROM AUTHOR]

The authors investigated the effects of postural manipulation on head movement control in infants from birth to 4 months of age. Eighteen full-term infants were presented with a card, which was moved from side to side before their eyes in 3 positions: unsupported supine, supported supine, and supported reclined. The results showed a higher proportion of initial position of head at midline and midline-to-side trajectory, improving the alignment of head and trunk; fewer movement units and movement units after peak velocity; lower mean angular velocity and peak velocity; and a broader rotation of the head in both supported positions. Thus, external support of the head promoted head and trunk alignment, improving stability and enabling the infant to execute better-controlled head movements. These findings may be helpful in early intervention and treatment of at-risk infants. [ABSTRACT FROM PUBLISHER]

Abstract: It is established that the body position influences verticality perception. In contrast, the possible influence of the awareness of the body orientation on verticality perception has never been investigated. This hypothesis, explored in the present study, is supported by the role played by the parietal cortex and the insula in both body position awareness and verticality perception. Nine subjects were asked to estimate the direction of the visual vertical (VV) by 12 adjustments of a luminous line in three conditions: (1) a control condition (subjects were upright and aware of their position), (2) a condition of congruence between the lateral body tilt and the awareness of this tilt, and (3) a condition of dissociation of subjective and objective orientations (tilted subjects who felt upright). The dissociation between objective and subjective orientations was obtained by inducing experimentally a postural vertical (PV) bias through 5min of lateral body tilt at 30° in darkness in a motorized flight simulator (mean 8.8°±4; min 6.2°; max 17.4°). VV orientation and variability were measured (expressed below in this order). As compared to the upright condition (0.3°±0.2; 0.8°±0.5), subjects showed similar VV orientation (0.1°±0.6; p=0.82) but an increased variability (1.4°±0.5; p<0.001) when tilted and aware of their tilt. In contrast, when they were tilted but felt upright, VV was biased in the direction of body tilt (2°±0.5; p<0.005) without increase of variability (0.9°±0.5; p=0.7). Our study reveals that the awareness of body orientation modulates verticality representation, which means that in addition to sensory integration, mental processes play also a role in the sense of verticality. We propose a novel model of verticality representation, based both on bottom-up and top-down processes. [Copyright &y& Elsevier]

After a period of stepping on a rotating platform, blindfolded subjects demonstrate a tendency to unconsciously turn when stepping in place, an after-effect known as podokinetic after-rotation (PKAR). Recent studies have also reported a change in postural orientation following the adaptive period and have suggested that this is causally related to PKAR. Here, we assess changes in trunk orientation following platform adaptation and determine their relationship to PKAR. Specifically, we determine whether a reorganized standing posture causes PKAR. Ten subjects stepped on a platform rotating at 60°/s for 10 min, with a cadence of 100 steps/min. Following adaptation, a significant PKAR response was seen, with a mean yaw rotation velocity of 6.0 ± 2.2°/s. In addition to this dynamic after-effect, there was a significant twist of the trunk with respect to the feet when standing still (6.9° ± 4.5°; mean ± SD), confirming the presence of a postural reorientation after-effect. However, the magnitudes of the two after-effects did not correlate ( r = 0.06, p = 0.87). Furthermore, in a second experiment, a prolonged passive twist of the trunk was used to induce postural reorientation. However, in this case, PKAR was not induced. These results demonstrate that PKAR is not an automatic consequence of reorganized standing posture. [ABSTRACT FROM AUTHOR]

Pusher syndrome is classically described as disorder of body orientation in the coronal plane. It is characterized by a tilt towards the contralesional paretic side and a resistance to external attempts to rectify. It occurs mainly in stroke patients, however, non-stroke causes have been described too. In 2010 the concept of the posterior pusher syndrome had been proposed, defined as disturbance of body orientation in the sagittal plane with imbalance, posterior tilt and an active resistance to forward pulling or pushing. The author describes, on the basis of the literature and own research, symptoms and methods of the treatment of the little-known posterior pusher syndrome. [ABSTRACT FROM AUTHOR]

Abstract: We studied the effect of static pitch body tilts on the perception of self-motion direction induced by a visual stimulus. Subjects were seated in front of a screen on which was projected a 3D cluster of moving dots visually simulating a forward motion of the observer with upward or downward directional biases (relative to a true earth horizontal direction). The subjects were tilted at various angles relative to gravity and were asked to estimate the direction of the perceived motion (nose-up, as during take-off or nose-down, as during landing). The data showed that body orientation proportionally affected the amount of error in the reported perceived direction (by 40% of body tilt magnitude in a range of ±20°) and these errors were systematically recorded in the direction of body tilt. As a consequence, a same visual stimulus was differently interpreted depending on body orientation. While the subjects were required to perform the task in a geocentric reference frame (i.e., relative to a gravity-related direction), they were obviously influenced by egocentric references. These results suggest that the perception of self-motion is not elaborated within an exclusive reference frame (either egocentric or geocentric) but rather results from the combined influence of both. [ABSTRACT FROM AUTHOR]

Abstract: Patients with postchiasmatic visual field defects often show a contralesional bias towards the scotoma in line bisection or when indicating their visual subjective straight ahead (VSSA). Recent evidence suggests a retinotopic misrepresentation of visual space in patients with homonymous quadrantanopia (HQ). We therefore assessed in the present study whether patients with HQ show an oblique shift of their VSSA towards their scotoma, in addition to the known bias in horizontal line bisection. Moreover, we examined whether eccentric fixation contributes to this shift. To this purpose, 15 non-neglecting stroke patients with HQ and 15 matched healthy control subjects were assessed in horizontal line bisection and in the horizontal and vertical dimension of their VSSA. Additionally, perimetric blind spot mapping was performed. Eight out of nine patients with left quadranopia showed the typical leftsided, horizontal line bisection error, while only one out of seven patients with rightsided quadranopia showed a rightsided shift. Normal subjects showed a non-significant leftward shift in line bisection (pseudoneglect). All 15 patients with HQ showed a large oblique shift of their VSSA towards the blind quadrants, while normal subjects showed no systematic left-rightward shift, but a small downward shift of the VSSA. The position of the blind spot was normal in all testable eyes of patients and control subjects, thus excluding eccentric fixation or cyclorotation of the eyes. In conclusion, our study reveals a hitherto unreported oblique spatial shift of subjective visual body orientation towards the blind quadrants in non-neglecting patients with quadranopia. [ABSTRACT FROM AUTHOR]

Two studies examined the perceptions that men have of images of male ideals as a function of whether appearance or performance was emphasized. In Study 1 (N = 54 men) male ideals that stressed appearance were rated as more muscular, more masculine and more attractive than male ideals that stressed performance. In Study 2 (N = 62 men) differences in the presentation of male ideals contributed not only to differences in perceptions of physical attributes but also to judgments of personality and behavioural tendencies of male ideals. In addition to discussing the implications and limitations of the current investigation, avenues for future research are outlined [ABSTRACT FROM AUTHOR]

Background: To date, there are very few studies on postural stability in older adults using body movement recordings to capture the postural movement pattern. Moreover, the importance of proprioception at key areas such as the calf or neck on the postural movement pattern in older adults has rarely been investigated. Objective: To investigate whether the body movement coordination strategy to calf or neck vibration was affected by aging. Methods: Body movement measurements were taken at five locations (ankle, knee, hip, shoulder and head) from 18 younger (mean age 29.1 years) and 16 older (mean age 71.5 years) adult subjects using a 3D movement measuring system while subjected to 50 s of pseudo-random calf or neck vibratory stimulation pulses with eyes open or closed. The positions from the knee, hip, shoulder and head markers were correlated against one another to give an indication of the body coordination. Results: During quiet standing, older adults had greater correlation between the head and trunk than the young. There was an age effect in the body movement coordination strategy. Older adults had a different movement pattern with neck vibration involving mainly more independent knee movements, indicating balance difficulty. Conclusions: Neck vibration affects the movement pattern in older adults more compared with younger adults and calf vibration, suggesting that, the regulation of body orientation in older adults is more difficult, especially during cervical proprioceptive disturbances. Copyright © 2009 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Abstract: Body orientation and eye gaze influence how information is conveyed during face-to-face communication. However, the neural pathways underpinning the comprehension of social cues in everyday interaction are not known. In this study we investigated the influence of addressing vs. non-addressing body orientation on the neural processing of speech accompanied by gestures. While in an fMRI scanner, participants viewed short video clips of an actor speaking sentences with object- (O; e.g., shape) or person-related content (P; e.g., saying goodbye) accompanied by iconic (e.g., circle) or emblematic gestures (e.g., waving), respectively. The actor''s body was oriented either toward the participant (frontal, F) or toward a third person (lateral, L) not visible. For frontal vs. lateral actor orientation (F>L), we observed activation of bilateral occipital, inferior frontal, medial frontal, right anterior temporal and left parietal brain regions. Additionally, we observed activity in the occipital and anterior temporal lobes due to an interaction effect between actor orientation and content of the communication (PF>PL)>(OF>OL). Our findings indicate that social cues influence the neural processing of speech–gesture utterances. Mentalizing (the process of inferring the mental state of another individual) could be responsible for these effects. In particular, socially relevant cues seem to activate regions of the anterior temporal lobes if abstract person-related content is communicated by speech and gesture. These new findings illustrate the complexity of interpersonal communication, as our data demonstrate that multisensory information pathways interact at both perceptual and semantic levels. [Copyright &y& Elsevier]

The article presents a study which investigates the influence of body orientation on the passive and active motion detection for the reproduction of joint position. It states that the study tested the shoulder proprioception of 28 healthy people while lying and sitting supine. It notes that there was interaction found between movement direction and body orientation. Moreover, it concludes that proprioception errors are not affected by the body orientation.

Abstract: Whether the vertical body orientation depends on the initial posture and/or the type of straightening up movement is the main question raised in this paper. Another objective was to specify the compensatory role of visual input while adopting an erected posture during microgravity. The final body orientation was analysed in microgravity during parabolic flights. After either (1) straightening up movement from a crouching or (2) a sitting posture, with and without vision. The main results are the following: (1) a vertical erected final posture is correctly achieved after sit to stand movement, whereas all subjects were tilted forward after straightening up from a crouching posture and (2) vision may contribute to correct final posture. These results suggest the existence of a re-weighting of the remaining sensory information, visual information, contact cutaneous cues and proprioceptive information under microgravity condition. We can put forward the alternative hypothesis that the control of body orientation under microgravity condition may also be achieved on the basis of a postural body scheme, that seems to be dependant on the type of movement and/ or the initial position of the whole body. [Copyright &y& Elsevier]

Abstract: This study examines ESL tutoring openings and closings. The data come from real-time dialogues involving tutors who are native speakers of American English and students who are in the process of improving their communication skills in English. Drawing on the method of conversation analysis, the study explores on a turn-by-turn basis the coordination of speech, gaze, and body orientation during the course of the participants’ tutorial interaction. Specifically, it analyzes the extent to which participants’ vocal and nonvocal actions contribute to the co-construction of ESL tutorial discourse as a collaborative activity. The study has implications for the native–nonnative dichotomy in second language discourse and for the notion of interactional asymmetry. [Copyright &y& Elsevier]

We investigated the influence of gaze elevation on judging the possibility of passing under high obstacles during pitch body tilts, while stationary, in absence of allocentric cues. Specifically, we aimed at studying the influence of egocentric references upon geocentric judgements. Seated subjects, orientated at various body orientations, were asked to perceptually estimate the possibility of passing under a projected horizontal line while keeping their gaze on a fixation target and imagining a horizontal body displacement. The results showed a global overestimation of the possibility of passing under the line, and confirmed the influence of body orientation reported by Bringoux et al. (Exp Brain Res 185(4):673–680, ). More strikingly, a linear influence of gaze elevation was found on perceptual estimates. Precisely, downward eye elevation yielded increased overestimations, and conversely upward gaze elevation yielded decreased overestimations. Furthermore, body and gaze orientation effects were independent and combined additively to yield a global egocentric influence with a weight of 45 and 54%, respectively. Overall, our data suggest that multiple egocentric references can jointly affect the estimated possibility of passing under high obstacles. These results are discussed in terms of “interpenetrability” between geocentric and egocentric reference frames and clearly demonstrate that gaze elevation is involved, as body orientation, in geocentric spatial localization. [ABSTRACT FROM AUTHOR]

Previous studies have shown that the perception of the earth-based visual horizon, also named Gravity Referenced Eye Level (GREL), is modified by body tilt around a trans-ocular axis. Here, we investigated whether estimates of the elevation of a luminous horizontal line presented on a screen in otherwise darkness and estimates of the possibility of passing under are identically related to body tilt in absence of motion. Results showed that subjects overestimated the elevation of the projected line, whatever their body orientation. In the same way, subjects also overestimated their capacity of passing under the line. Both estimates appeared as a linear function of body tilt, that is, forward body tilt yielded increased overestimations, and backward body tilt yielded decreased overestimations. More strikingly, the linear effect of body tilt upon these estimates is comparable to that previously observed for direct GREL judgements. Overall, these data strongly suggest that the perception of the elevation of a visible obstacle and the perception of the ability of passing under in otherwise darkness shared common processes which are intimately linked to the GREL perception. The effect of body tilt upon these perceptions may illustrate an egocentric influence upon the semi-geocentric frame of reference required to perform the task. Possible interactions between egocentric and geocentric frames of reference are discussed. [ABSTRACT FROM AUTHOR]

The representation of the vertical can be assessed by measuring the visual, tactile or perception of the postural vertical (PV). It is well accepted that visceral graviceptors and Golgi tendon receptors contribute to perception of the PV, whereas the role of muscular proprioception (Ia muscle spindles) remains to be clarified. The objective of this study was to analyze whether or not muscular proprioception contributes to the representation of verticality. We hypothesized that the modulation of proprioception by appropriate tendinomuscular vibration may tilt the PV. We present two experiments that explore this hypothesis. PV was firstly measured in the pitch plane in twelve healthy subjects in two conditions: baseline and vibration of both Achilles tendons during six minutes, according to a counterbalanced presentation. PV orientation (mean) and dispersion (standard deviation) were calculated on the six measurements per condition. Vibration of the Achilles tendons induced a systematic backward tilt of PV (2.7° ± 0.8° on average; P < 10−3), and no significant changes regarding PV dispersion. A clear post-effect was found for PV orientation in subjects who started the experiment with the condition vibration on. The possibility that PV could also be modulated by a much shorter duration of vibration (less than 8 s of vibration) was analyzed in a second experiment using a similar general procedure but a simplified experimental plane in other subjects. Again a backward PV tilt was induced by the vibration, but with a magnitude lower than that found in the first experiment, and with no post-effect. Since body geometry was unchanged, these two studies mean that proprioception contributes to the representation of the vertical. In conclusion, this study brings new insights to our understanding of the sense of verticality and contributes to the interpretation of backward falls induced by vibration. The induced backward fall is partly due to alignment of the erect posture with a backward-tilted referential of verticality. [ABSTRACT FROM AUTHOR]

Abstract: Although research suggests that experience may be a better indicator of the acquisition of certain abilities by infants than age, little work addresses this issue in the development of reaching movements in particular. This longitudinal study fills this gap by verifying the effect of practice time on more- and less-skilled reachers of the same age group in different body orientations. Less- (n =6) and more-skilled (n =4) reachers were evaluated at the acquisition of reaching and again after 1 month of spontaneous practice. Kinematic analyses examined 3D wrist motion during reaching trials in supine (0°), reclined (45°) and seated (70°) orientations. The results indicated that skill level was a relevant factor in dealing with gravitational constraints imposed by different body orientations. Time of practice affected the way less- and more-skilled reachers explored and adapted the kinematic parameters of reaching to constraints imposed by body orientations. These findings suggest that not only age, but also experience and body orientations are important constraints that should be taken into account when examining infant reaching development. [Copyright &y& Elsevier]

The otoliths are stimulated in the same fashion by gravitational and inertial forces, so otolith signals are ambiguous indicators of self-orientation. The ambiguity can be resolved with added visual information indicating orientation and acceleration with respect to the earth. Here we present a Bayesian model of the statistically optimal combination of noisy vestibular and visual signals. Likelihoods associated with sensory measurements are represented in an orientation/acceleration space. The likelihood function associated with the otolith signal illustrates the ambiguity; there is no unique solution for self-orientation or acceleration. Likelihood functions associated with other sensory signals can resolve this ambiguity. In addition, we propose two priors, each acting on a dimension in the orientation/acceleration space: the idiotropic prior and the no-acceleration prior. We conducted experiments using a motion platform and attached visual display to examine the influence of visual signals on the interpretation of the otolith signal. Subjects made pitch and acceleration judgments as the vestibular and visual signals were manipulated independently. Predictions of the model were confirmed: (1) visual signals affected the interpretation of the otolith signal, (2) less variable signals had more influence on perceived orientation and acceleration than more variable ones, and (3) combined estimates were more precise than single-cue estimates. We also show that the model can explain some well-known phenomena including the perception of upright in zero gravity, the Aubert effect, and the somatogravic illusion. [ABSTRACT FROM AUTHOR]

Abstract: Vibration applied to the Achilles tendon is well known to induce in freely standing subjects a backward body displacement and in restrained subjects an illusory forward body tilt. The purpose of the present experiment was to evaluate the effect of Achilles tendon vibration (90Hz) on postural orientation in subjects free of equilibrium constraints. Subjects (n =12) were strapped on a backboard that could be rotated in the antero-posterior direction with the axis of rotation at the level of the ankles. They stood on a rigid horizontal floor with the soles of their feet parallel to the ground. They were initially positioned 7° backward or forward or vertical and were required to adjust their body (the backboard) to the vertical orientation via a joystick. Firstly, results showed that in response to Achilles tendon vibration, subjects adjusted their body backward compared to the condition without vibration. This backward body adjustment likely cancel the appearance of an illusory forward body tilt. It was also observed that the vibratory stimulus applied to the Achilles tendon elicited in restrained standing subjects an increased EMG activity in both the gastrocnemius lateralis and the soleus muscles. Secondly, this vibration effect was more pronounced when passive displacement during the adjustment phase was congruent with the simulated elongation of calf muscles. These results indicated that the perception of body orientation is coherent with the postural response classically observed in freely standing subjects although the relationship between these two responses remains to be elucidated. [Copyright &y& Elsevier]

Abstract: Many studies have demonstrated that the seated position is more effective in promoting reaching movements when compared with supine. The aim of this longitudinal study was to verify the effect of seated and supine positions on spatio-temporal parameters of reaching in 4–6-month-old infants. Four infants were observed during reaching trials in both positions. A total of 235 reaches were analyzed by using the 3D movement reconstruction. Our results showed that frequency of reaching and straightness index increased over age. Significant differences between the positions were observed at 4 months, when the frequency increased and the duration and deceleration time decreased in the seated position. There were no significant differences at 5 and 6 months. These findings suggest that young infants are able to change kinematical parameters of reaching to adapt themselves to intrinsic and extrinsic constraints (i.e. age and position). [Copyright &y& Elsevier]

Abstract: We investigate the role of vestibular information in judging the gravity-referenced eye level (i.e., earth-referenced horizon or GREL) during sagittal body tilt whilst seated. Ten bilateral labyrinthine-defective subjects (LDS) and 10 age-matched controls set a luminous dot to their perception of GREL in darkness, with and without arm pointing. Although judgements were linearly influenced by the magnitude of whole-body tilt, results showed no significant difference between LDS and age-matched controls in the subjective GREL accuracy or in the intra-subject variability of judgement. However, LDS performance without arm pointing was related to the degree of vestibular compensation inferred from another postural study performed with the same patients. LDS did not utilize upper limb input during arm pointing movements as a source of graviceptive information to compensate for the vestibular loss. The data suggest that vestibular cues are not of prime importance in GREL estimates in static conditions. The absence of difference between controls and LDS GREL performance, and the correlation between the postural task and GREL accuracy, indicate that somatosensory input may convey as much graviceptive information required for GREL judgements as the vestibular system. [Copyright &y& Elsevier]

Abstract: The present study investigated a cognitive aspect upon spatial perception, namely the impact of a true or false verbal feedback (FB) about the magnitude of body tilt on Subjective Proprioceptive Horizon (SPH) estimates. Subjects were asked to set their extended arm normal to gravity for different pitch body tilts up to 9°. True FB were provided at all body tilt angles, whereas false FB were provided only at 6° backward and 6° forward body tilts for half of the trials. Our data confirmed previous results about the egocentric influence of body tilt itself upon SPH: estimates were linearly lowered with forward tilts and elevated with backward tilts. In addition, results showed a significant effect of the nature of the external FB provided to the subjects. When subjects received a false FB inducing a 3° forward bias relative to physical body tilt, they set their SPH consequently higher than when they received a false FB inducing a 3° backward bias. These findings clearly indicated that false cognitive information about body tilt might significantly modify the judgement of a geocentric direction of space, such as the SPH. This may have deleterious repercussions in aeronautics when pilots have to localize external objects relative to earth-based directions in darkened environments. [Copyright &y& Elsevier]

This work investigated the accuracy of the perception of the main orientations (i.e., vertical and horizontal orientations) with the kinesthetic modality––a modality not previously used in this field of research. To further dissociate the influence of the postural and physical verticals, two body positions were explored (supine and upright). Twenty-two blindfolded participants were asked to set, as accurately as possible, a rod to both physical orientations while assuming one of the two body positions. The horizontal was perceived more accurately than the vertical orientation in the upright position but not in the supine position. Essentially, there were no differences in the supine position because the adjustments to the physical vertical were much more accurate than they were in the upright position. The lower accuracy in the estimation of the vertical orientation observed in the upright position might be linked to the dynamics associated with the maintenance of posture. [Copyright &y& Elsevier]

We investigated the effects of whole body tilt and lifting the arm against gravity on perceptual estimates of the Gravity-Referenced Eye Level (GREL), which corresponds to the subjective earth-referenced horizon. The results showed that the perceived GREL was influenced by body tilt, that is, lowered with forward tilt and elevated with backward tilt of the body. GREL estimates obtained by arm movements without vision were more biased by whole-body tilt than purely visual estimates. Strikingly, visual GREL estimates became more dependent on whole-body tilt when the indication of level was obtained by arm lifting. These findings indicate that active motor involvement and/or the addition of kinesthetic information increases the body tilt-induced bias when making GREL judgements. The introduction of motor/kinaesthetic cues may induce a switch from a semi-geocentric to a more egocentric frame of reference. This result challenges the assumption that combining non-conflicting multiple sensory inputs and/or using intermodal information provided during action should improve perceptual performance. [ABSTRACT FROM AUTHOR]

Abstract: “Pusher syndrome” is classically described as a disorder of body orientation in the coronal plane. Although it mainly occurs in stroke patients, non-stroke causes have been described. Pusher behaviour is characterized by a tilt towards the contralesional paretic side and a resistance to external attempts to rectify. It may occur with or without hemispatial neglect, which in itself may be the cause of a usually ipsilesional shift of attention and body orientation in the axial plane. In this report we describe two patients with a marked disturbance of body orientation in the sagittal plane with imbalance, posterior tilt and an active resistance to forward pulling or pushing. By analogy we propose the term “posterior pusher” syndrome for the clinical picture. [Copyright &y& Elsevier]

The article identifies the human locomotion paths using the mathematical models of locomotion and numerical inverse optimisation techniques. The study shows that the objective function is a combination of several factors such as time, length and jerk. However, the rotational components of jerk and acceleration do not play any role. It emphasizes that the cost of function of natural human path generation in free space is determined through inverse optimal control technique.

Animals living in desert environments have to be adaptable to significant temperature shifts in their surroundings. Ungulates have behavioral adaptations to adjust to thermoregulation problems and use the landscape features to lessen the effects of thermal fluctuations. In this paper, I investigated the usage of the local landscape by goitered gazelles (Gazella subgutturosa) in natural conditions to better understand behavioral adaptations of wild species to a northern arid environment. I found that during the hottest weather, goitered gazelle females and fawns used the shade of vegetation more often than males, while males preferred more elevated, windier places; while during winter, goitered gazelles of both sexes used deep, dry river beds in the foothills as a shelter against the strong winds in winter and early-spring. Body orientation with of pointing the hindquarters toward the wind was used infrequently than other protective behaviors. The sands of dry river beds were the most selected places for goitered gazelles to rest all year round, especially during the cold season. Using the microclimate features of the landscape is a very important part of the goitered gazelles' adaptations, which help to reduce the costs associated with body thermoregulation and to endure the heavy heat load during summers and the severe harsh cold during winters. • Goitered gazelle males used more elevated windier areas during hot weather. • Females and especially fawns preferred shade of shrubs/trees during summer. • Smaller fawns stayed in shade more often than adults. • Goitered gazelles seek windless places during cold months. • Goitered gazelles used landscape features for effective body thermoregulation. [ABSTRACT FROM AUTHOR]

Image based human behavior and activity understanding has been a hot topic in the field of computer vision and multimedia. As an important part, skeleton estimation, which is also called pose estimation, has attracted lots of interests. For pose estimation, most of the deep learning approaches mainly focus on the joint feature. However, the joint feature is not sufficient, especially when the image includes multi-person and the pose is occluded or not fully visible. This paper proposes a novel multi-task framework for the multi-person pose estimation. The proposed framework is developed based on Mask Region-based Convolutional Neural Networks (R-CNN) and extended to integrate the joint feature, body boundary, body orientation and occlusion condition together. In order to further improve the performance of the multi-person pose estimation, this paper proposes to organize the different information in serial multi-task models instead of the widely used parallel multi-task network. The proposed models are trained on the public dataset Common Objects in Context (COCO), which is further augmented by ground truths of body orientation and mutual-occlusion mask. Experiments demonstrate the performance of the proposed method for multi-person pose estimation and body orientation estimation. The proposed method can detect 84.6% of the Percentage of Correct Keypoints (PCK) and has an 83.7% Correct Detection Rate (CDR). Comparisons further illustrate the proposed model can reduce the over-detection compared with other methods. [ABSTRACT FROM AUTHOR]