Recognition of dance-like actions: Memory for static posture or dynamic movement?

Bilateral vestibulopathy (BV) is a chronic vestibular disorder, characterized by bilaterally absent or significantly impaired vestibular function. Symptoms typically include, but are not limited to, unsteadiness and movement-induced blurred vision (oscillopsia). This prospective case–control study aimed to elucidate the impact of BV on cognitive and motor performance and on cognitive–motor interference. Cognitive and motor performance, as well as cognitive–motor interference were measured in persons with BV and normal hearing using the 2BALANCE dual-task protocol. The experimental group was matched to a healthy control group based on age, sex, and educational level. The 2BALANCE protocol comprises cognitive tests assessing visuospatial memory, mental rotation, visual and auditory response inhibition, visual and auditory working memory, and processing speed. The cognitive tests were performed in single-task condition (while seated), and in dual-task condition (during a static and a dynamic motor task). The static motor task consisted of balancing on a force platform with foam pad. The dynamic motor task consisted of walking at a self-selected speed. These motor tasks were also performed in single-task condition. A generalized estimating equations model was used to investigate group differences for all cognitive and motor outcome measures. The estimated marginal means, as well as the odds ratios (OR), and their 95% confidence intervals (CI) were calculated. For the backward digit recall test, a baseline measurement was performed and analyzed using a student-t test. A total of 22 patients with BV and normal hearing and 22 healthy control subjects were assessed [mean age (SD), BV = 53.66 (13.35) and HC = 53.21 (13.35), 68% male]. The BV group had poorer mental rotation skills in single-task condition, compared to the control group [odds ratio (OR) = 2.30, confidence interval (CI) = 1.12–4.73, P = 0.024]. Similarly, auditory and visual working memory were also poorer in the BV group in single-task condition (P = 0.028 and P = 0.003, respectively). The BV group also performed poorer on the mental rotation task and the visual response inhibition task in dual-task condition (OR = 2.96, CI = 1.57–5.59, P < 0.001 and OR = 1.08, CI = 1.01–1.16, P = 0.032, respectively). Additionally, an interaction effect, indicating increased cognitive–motor interference in the BV group, was observed for mental rotation, response inhibition, and auditory working memory (P = 0.003 to 0.028). All static motor outcome parameters indicated more postural sway in the BV group compared to the control group for all test conditions (P < 0.001 to 0.026). No group differences were noted for the dynamic motor task. These findings suggest a link between vestibular function and cognitive performance, as well as a greater interference between cognitive and motor performance in BV, compared to healthy controls.

This paper describes the initial evaluation of an electronic system that makes use of accelerometers that act as electronic inclinometers during static or semi-static (constant angular velocity) conditions and estimates angles with respect to gravity within 2 to 3 degrees. The accelerometers are attached directly to the body near the joint of interest and have been used to estimate shoulder, knee and trunk flexion. A study was conducted to evaluate the accuracy of the electronic inclinometer system to evaluate body postures. Measurements were made with a manual goniometer or weighted inclinometer and the electronic inclinometers simultaneously as 5 subjects who wore the device assumed a variety of different static postures. Several calibration procedures for each body region, ranging from no calibration for the individual to relatively involved calibration procedures, were used in the evaluation. The electronic inclinometers predicted shoulder, knee and trunk flexion to within about 5 to 10 degrees of the manual instruments with no or relatively simple calibration procedures. These preliminary results suggest that the electronic system may be useful for nearly continuous and simultaneous postural evaluation of multiple body parts with relatively little interference to working postures, at least for relatively static body postures.

BackgroundAbnormal dynamic knee moments and variations of static foot posture are risk factors for chronic lower limb injury development. However, relationships between the two have yet to be established in...

Patient compliance is important when assessing movement, particularly in a free-living environment when patients are asked to don their own accelerometers. Reducing the number of accelerometers could increase patient compliance. The aims of this study were (1) to determine and compare the validity of different accelerometer combinations and placements for a previously developed posture and dynamic movement identification algorithm. Custom-built activity monitors, each containing one tri-axial accelerometer, were placed on the ankles, right thigh, and waist of 12 healthy adults. Subjects performed a protocol in the laboratory including static orientations of standing, sitting, and lying down, and dynamic movements of walking, jogging, transitions between postures, and fidgeting to simulate free-living activity. When only one accelerometer was used, the thigh was found to be the optimal placement to identify both movement and static postures, with a misclassification error of 10%, and demonstrated the greatest accuracy for walking/fidgeting and jogging classification with sensitivities and positive predictive value (PPVs) greater than 93%. When two accelerometers were used, the waist-thigh accelerometers identified movement and static postures with greater accuracy than the thigh-ankle accelerometers (with a misclassification error of 11% compared to 17%). However, the thigh-ankle accelerometers demonstrated the greatest accuracy for walking/ fidgeting and jogging classification with sensitivities and PPVs greater than 93%. Movement can be accurately classified in healthy adults using tri-axial accelerometers placed on one or two of the following sites: waist, thigh, or ankle. Posture and transitions require an accelerometer placed on the waist and an accelerometer placed on the thigh.

In the era of Industry 4.0, artificial intelligence technology is experiencing rapid development, and the integration of artificial intelligence (AI) with flexible sensors has emerged as a transformative approach for human motion and posture sensing. This paper explores the advancements in AI-enhanced flexible sensors, focusing on the application of flexible sensors on various parts of the human body. Flexible sensors, due to their conformability and sensitivity, are ideal for capturing the dynamic and subtle movements of the human body. AI algorithms, particularly machine learning and deep learning techniques are employed to process the complex data streams from these sensors, enabling the accurate recognition and prediction of various human postures and motions. The combination of these technologies overcomes the limitations of traditional sensing systems, offering higher precision, adaptability, and real-time feedback. It can be applied to healthcare for rehabilitation monitoring, sports for performance enhancement, and human-computer interaction for intuitive control. This review also discusses the challenges such as sensor reliability, data privacy, and power management. The future outlook emphasizes more sophisticated AI models and deeper technology integration, promising a seamless integration into everyday life for enhanced human-machine interaction and health monitoring.

We propose in this paper a computer vision-based posture recognition method for home monitoring of the elderly. The proposed system performs human detection prior to the posture analysis; posture recognition is performed only on a human silhouette. The human detection approach has been designed to be robust to different environmental stimuli. Thus, posture is analyzed with simple and efficient features that are not designed to manage constraints related to the environment but only designed to describe human silhouettes. The posture recognition method, based on fuzzy logic, identifies four static postures and is robust to variation in the distance between the camera and the person, and to the person's morphology. With an accuracy of 74.29% of satisfactory posture recognition, this approach can detect emergency situations such as a fall within a health smart home.

Research has shown that driver inattention is the most prevalent cause of traffic collisions accounting for an estimated 25 to 56% of crashes in the US. Driver inattention may result from drivers engagement in secondary activities (such as texting or cell phone use), or lack of awareness of the surrounding environment. The main objective of this research is to investigate the relationship between potentially unsafe driving events and the actual driver body posture and movements when performing a driving maneuver under different traffic configurations. The paper presents results from a pilot study that captured the 3-D posture and activity of three drivers while performing both mandatory (merging) and discretionary (lane changing) maneuvers on freeway and arterial segments in Gainesville, Florida. The body posture of the drivers was captured through the use of a low-cost infrared depth sensor. A 7-point human skeletal model was fit to the captured depth frame sequences using our proposed framework. The comparative analysis of the participants’ body movements while performing the maneuvers revealed differences between the participants’ body activity when performing the same maneuvers. The findings of this research provide significant insights regarding which body movements may hide unsafe situations while performing a driving maneuver that requires the attention of the surrounding environment.

Social interaction and comprehension of non-verbal behaviour requires a representation of people’s bodies. Research into the neural underpinnings of body representation implicates several brain regions including extrastriate and fusiform body areas (EBA and FBA), superior temporal sulcus (STS), inferior frontal gyrus (IFG) and inferior parietal lobule (IPL). The different roles played by these regions in parsing familiar and unfamiliar body postures remain unclear. We examined the responses of this body observation network to static images of ordinary and contorted postures by using a repetition suppression design in functional neuroimaging. Participants were scanned whilst observing static images of a contortionist or a group of objects in either ordinary or unusual configurations, presented from different viewpoints. Greater activity emerged in EBA and FBA when participants viewed contorted compared to ordinary body postures. Repeated presentation of the same posture from different viewpoints lead to suppressed responses in the fusiform gyrus as well as three regions that are characteristically activated by observing moving bodies, namely STS, IFG and IPL. These four regions did not distinguish the image viewpoint or the plausibility of the posture. Together, these data define a broad cortical network for processing static body postures, including regions classically associated with action observation.

Investigating acute stress responses is crucial to understanding the underlying mechanisms of stress. Current stress assessment methods include self-reports that can be biased and biomarkers that are often based on complex laboratory procedures. A promising additional modality for stress assessment might be the observation of body movements, which are affected by negative emotions and threatening situations. In this paper, we investigated the relationship between acute psychosocial stress induction and body posture and movements. We collected motion data from N = 59 individuals over two studies (Pilot Study: N = 20, Main Study: N = 39) using inertial measurement unit (IMU)-based motion capture suits. In both studies, individuals underwent the Trier Social Stress Test (TSST) and a stress-free control condition (friendly-TSST; f-TSST) in randomized order. Our results show that acute stress induction leads to a reproducible freezing behavior, characterized by less overall motion as well as more and longer periods of no movement. Based on these data, we trained machine learning pipelines to detect acute stress solely from movement information, achieving an accuracy of 75.0±17.7%\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$${75.0 \\pm 17.7}{\\%}$$\\end{document} (Pilot Study) and 73.4±7.7%\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$${73.4 \\pm 7.7}{\\%}$$\\end{document} (Main Study). This, for the first time, suggests that body posture and movements can be used to detect whether individuals are exposed to acute psychosocial stress. While more studies are needed to further validate our approach, we are convinced that motion information can be a valuable extension to the existing biomarkers and can help to obtain a more holistic picture of the human stress response. Our work is the first to systematically explore the use of full-body body posture and movement to gain novel insights into the human stress response and its effects on the body and mind.

BackgroundMigraine and temporomandibular disorders (TMDs) are reported to be associated. However, there are no reports on the association among migraines, TMDs and changes in body posture. ObjectivesTo assess changes in body posture in women suffering migraines with or without TMD compared with a control group. MethodSixty-six women with a mean age of 18 to 45 years participated in this study. The groups were composed of 22 volunteers with migraine and TMD (MTMD), 22 volunteers with migraines without TMD (MG) and 22 women in the control group (CG). Static posture was assessed by photogrammetry, and 19 angles were measured. ResultsPostural asymmetry was observed in the face for 4 angles measured on the frontal plane in the MG group and for 4 angles of the trunk in the MG and MTMD groups with respect to CG. However, for comparisons between MTMD and CG, clinical relevance was identified for two angles of the sagittal plane (Cervical and Lumbar Lordosis, Effect Size - ES - moderate: 0.53 and 0.60). For comparisons between the MG and CG, the clinical relevance/potential was verified for three angles with moderate ES (ES>0.42). The clinical relevance when comparing MTMD and CG was identified for four angles of facial symmetry head inclination (ES>0.54) and for two angles between MG and CG (ES>0.48). Conclusion The results demonstrated the presence of postural changes compared with a control group in women with migraines with or without TMD, and there were similar clinically relevant postural changes among the patients with migraines with and without TMD.

The purpose of this discussion is to examine the expression of dynamic sports movements in deformative sculpture. Humans naturally produce various movements that have aesthetic value, both consciously and unconsciously. These movements appear in static daily activities and in structured physical activities such as sports, which are classified as dynamic movements. Dynamic movements have patterns, rhythms, and intensities that create strong, harmonious, and meaningful body expressions. Sports provide physical benefits while displaying beauty through variations in tempo, space, energy, and time. In sports such as swimming, running, and pole vaulting, athletes' movements demonstrate a combination of muscle strength, body flexibility, and balance that create high visual aesthetics. The beauty of these movements inspires the creation of works of art, particularly in deformative sculpture. Deformative styles are used to express human body movements at certain moments in sports. This sculpture aims to convey that sports are not only physical activities, but also as an expression of the beauty of body movements that can be appreciated artistically. Through this work, the author hopes to demonstrate that sports as a visual art has aesthetic value that deserves to be appreciated and interpreted more deeply.

100. The Dubousset Functional Test: a baseline analysis of a novel, multidomain assessment of physical function and balance

The present study explores the effects of FMS functional movement training on aerobic athletes' body posture coordination, and explores the application of FMS functional movement training to the promotion of aerobic athletes' physical performance. In aerobic exercise, body posture control ability is an important criterion for the expression of technical movements, the display of form art aesthetics, and the evaluation of aerobic competition performance. Physical training is the most basic way to improve body posture control, and FMS functional movement training is an emerging physical training mode in recent years, which attaches more importance to functional training than traditional physical training, does not improve athletes' self-confidence in a purposeful way, and has a relatively good improvement effect on technical movements with relatively high movement requirements.40 college aerobic athletes were randomly divided into two groups: Traditional physical training Group (T, N=20) and FMS functional movement training Group (F, N=20). The control group adopts the traditional physical training method, and the functional training group adopts the training method based on the functional movement design of FMS. The results showed that compared with before training, after the traditional physical training group and the FMS functional movement training group intervened, the subjects' FMS test improved significantly in all six motility movements (P&lt;0.05), but there was no significant difference in the straight bow squat and active orthogonal lifting test (P&gt;0.05). The body posture coordination in the dynamic movement and static movement of aerobics was significantly improved only in the FMS functional movement training group (P&lt;0.05).Conclusion: FMS functional training can relatively well promote aerobic athletes' body control ability and body posture coordination in the movement process, which is suitable for further application and dissemination in the physical fitness training of college aerobic athletes.After 12 weeks of training, the scores of various indicators of the experimental group were significantly higher than those of the control group before the experiment, and the results of the FMS test were significantly improved; the effect of the experimental group was better than that of the control group, reducing the incidence of exercise damage; the physical stability, flexibility and asymmetry of the experimental group athletes were improved, but the effect on active right angle rise and straight lunge squat was not obvious. In the body posture control ability test under the static movement plane change condition, the 8-step ventral bridge, 5-step lateral bridge and hexagonal bridge of the experimental group and the control group showed significant differences, and the experimental configuration results were better than the control group, and the before-and-after comparison of the experimental group was significant.It shows that FMS functional movement training can improve the body posture control ability of aerobic athletes in the static movement plane. In the test of aerobic athletes' body posture control ability under the condition of dynamic movement direction change, the results show that the improvement effect of the T-shaped, W-shaped and Y-shaped tests of aerobic combination steps of the experimental group before and after the experiment is better than that of the control group, and each indicator has a significant difference within the group, indicating that FMS functional movement training has improved the body posture control ability of aerobic athletes.

Objective. Proprioceptive information provides individuals with a sense of our limb’s static position and dynamic movement. Impaired or a lack of such feedback can diminish our ability to perform dexterous motions with our biological limbs or assistive devices. Here we seek to determine whether both static and dynamic components of proprioception can be recognized using variation of the spatial and temporal components of vibrotactile feedback. Approach. An array of five vibrotactors was placed on the forearm of each subject. Each tactor was encoded to represent one of the five forearm postures. Vibratory stimulus was elicited to convey the static position and movement of the forearm. Four experimental blocks were performed to test each subject’s recognition of a forearm’s simulated static position, rotational amplitude, rotational amplitude and direction, and rotational speed. Main results. Our results showed that the subjects were able to perform proprioceptive recognition based on the delivered vibrotactile information. Specifically, rotational amplitude recognition resulted in the highest level of accuracy (99.0%), while the recognition accuracy of the static position and the rotational amplitude-direction was the lowest (91.7% and 90.8%, respectively). Nevertheless, all proprioceptive properties were perceived with >90% accuracy, indicating that the implemented vibrotactile encoding scheme could effectively provide proprioceptive information to the users. Significance. The outcomes suggest that information pertaining to static and dynamic aspects of proprioception can be accurately delivered using an array of vibrotactors. This feedback approach could be used to potentially evaluate the sensorimotor integration processes during human–machine interactions, and to improve sensory feedback in clinical populations with somatosensory impairments.

Body movements play a crucial role in music performance and perception, and they do so well beyond those devoted to sound production itself. Various movements related to the performer’s emotional intentions or structural aspects of the music are also part of the performance and crucial to the listening experience. In the present study, we investigated the effect of instructed timing on such non-sound producing body movements, focusing on musicians’ body posture. We used an infrared motion-capture system to record the movements of skilled guitarists and bassists while they were playing electric guitar and electric bass, respectively. We instructed the musicians to perform under three different timing-style conditions: laid-back (behind), on-the-beat, and pushed (ahead). We also conducted short semistructured interviews to gain further insight into their movement strategies. The results show that performers generally leaned forward when instructed to play systematically slightly ahead of the pulse. We suggest that this change is related to an alteration in the performer’s experience of the feel of the music. The results support the view that musicians’ non-sound-producing body movements are not random, but integral to the performance, and that they are closely related to the music’s microrhythmic feel.