A number of studies have shown the importance of combining observation with practice when learning an action. Although the Point-Light Display (PLD) technique is frequently used in laboratory contexts to assess the mechanisms underlying observational learning, it has only been infrequently used in ecological contexts. The present study explored whether the components of complex weightlifting movements could be learned by means of an observational learning protocol. To that end, we compared three observation conditions: action observation (Video group), Point-Light Display observation (PLD group), and no human action observation (Control group). Twenty-six athletes participated in a weekly one-hour session for 5weeks to learn a complex weightlifting movement. During this period, the participants alternated between phases of movement observation, which varied depending on the condition to which they were assigned, and phases of movement execution. There were 12 sets consisting of 2min of observation and 6 physical repetitions per session. Joint angles at key moments, bar trajectories, and intersegmental coordination were assessed both before (Pre-test) and after (Retention tests) the learning period. The results indicate that both observation conditions had a larger effect on learning than the control condition. Furthermore, the PLD condition was more effective than the video condition for complex intersegmental coordination. This experiment therefore suggests that PLD observation combined with physical practice can be beneficial for the acquisition of complex movements.

Understanding emotions through biological motion in autism spectrum disorder: A systematic review

As autonomous vehicles become widespread, pedestrians must rapidly infer vehicle motion and yielding intent. Conventional symbolic eHMIs (e.g., text or icons) are language-dependent, culturally variable, and often difficult to detect in complex traffic scenes. We propose a non-symbolic communication framework based on biological motion, implemented as a point-light external human-machine interface (eHMI). In Study 1a (Chinese adults, N = 32), the bio-motion eHMI improved vehicle-movement comprehension relative to text and achieved comparable intent understanding. These benefits generalized to children aged 5–9 (Study 1b) and to a different cultural context (Study 1c). Study 2 showed that the bio-motion eHMI elicited earlier reductions in perceived crossing safety in non-yielding scenarios, supporting safer street-crossing decisions. Study 3 demonstrated enhanced detection distance for acceleration and deceleration changes. Overall, biological motion provides an intuitive, engaging, and culturally robust channel for vehicle-pedestrian communication.

Previous work has demonstrated that microsaccades play a key role in both preparation for upcoming sensory stimuli and visual attention. Microsaccadic modulation prior to a predictable event is observed with visual, tactile, and auditory stimuli, suggesting a common function across sensory modalities. This study investigated how microsaccade modulation relates to sensorimotor control in goal-directed reaching. We designed a task in which participants positioned their hand (represented as a cursor) at a start position and then fixated a target, which changed color after a variable delay. Depending on the condition, in response to this color change (go cue), participants waited for the trial end (cue monitoring), watched a cursor move with biological motion from the hand start position to the target (cursor tracking), or reached to the target either with (reach visible) or without (reach invisible) vision of the hand. We found that the rate of microsaccades was consistently reduced in anticipation of the visual cue. Microsaccade reduction immediately before the go cue was greatest in conditions that required active hand movement, suggesting that movement preparation added attentional load to the sensorimotor system. Following the go cue, microsaccades remained reduced in all conditions, indicating that not only external events but also self-generated movements are associated with event prediction. Yet, the reduction in microsaccade rate was not greater in the movement conditions, suggesting that sensorimotor control processes that are involved in predicting the sensory consequences of motor commands neither enhance nor reduce microsaccade rate.

BioMotion-SNN: Spiking neural network modeling for visual motion processing.

ABSTRACT Social anxiety disorder involves excessive fear of negative evaluation and threat-related perceptual biases, but little is known about how it shapes perception of biological motion at both individual and crowd levels. We explored whether social anxiety is related to biased approach judgments for single walkers and ensembles when depth is disambiguated. One hundred forty-seven Korean university students completed two tasks with three-dimensional point-light walkers containing perspective cues. In Task 1, participants judged whether a single walker with headings from 0° to 24° was approaching, yielding an individual detection threshold. In Task 2, they judged whether a crowd of 10 walkers (mixtures of 0° and threshold+6° headings) was, on average, approaching, yielding a point of subjective equality (PSE). Social anxiety was assessed with the Social Phobia Scale and Social Interaction Anxiety Scale. Depressive symptoms were included as a covariate. We found that individuals with high social anxiety exhibited lower thresholds and PSEs, indicating a stronger bias toward perceiving ambiguous movement as approaching. These preliminary findings are consistent with theoretical accounts of threat-related perceptual biases in social anxiety and point to potential contributions of both item-level and ensemble-level processes in dynamic social perception.

Referential signaling is a fundamental component of social interaction, enabling individuals to direct attention, convey intention, and establish shared understanding. The processing of referential signals operates across multiple levels of neurocognitive systems. First, innate mechanisms rapidly detect socially relevant cues, such as gaze and biological motion, prioritizing social information from infancy. Second, social learning enables the establishment of symbolic conventions in service of referential interactions, implicating the alignment of abstract representations across brains. Third, a deliberative system supports the flexible production and interpretation of referential signals in context by anticipating others' beliefs and motivation. Despite the diversity and complexity of these processes, recent research has made significant strides in identifying their neural and cognitive bases. Studies indicate that evolutionarily conserved subcortical pathways support early-emerging sensitivity, while cortical networks involved in social reasoning and decision-making underlie acquired and deliberative levels of processing. Future research is needed to clarify how these mechanisms interact across development and how their disruption contributes to neurodevelopmental conditions such as autism spectrum disorder.

This paper examines the effects of inclined magnetic field, channel rotation and viscous dissipation on the fluid flow of the ternary hybrid nanofluid (THNF) inside an anisotropic porous channel. The resulting nonlinear partial differential equations are further reduced to a set of ordinary differential equations under similarity transformations. These equations are solved numerically via MATLAB's ‘bvp4c’ function and results are further analysed using artificial neural network (ANN) model. The effects of key parameters in velocity profiles, temperature profiles, local skin friction and Nusselt number are discussed for the following: Hartmann number, Taylor's number, Darcy numbers, Eckert number and nanoparticles volume fraction. From the finding it is seen that the highest value of the correlation coefficient using ANN are R2 = 0.99999999 and R2 = 999999987, while the lowest value of MSE using both MSE = 5.7503 × 10−8 and MSE = 3.5238 × 10−7 respectively, signifying the prediction with high precision. The application of flow within a channel holds significant applicability in systems involving physiological flows such as blood transport through anisotropic biological tissues or fluid motion within rotating organs.

Continuous flash suppression (CFS) is widely used in research on unconscious visual processing due to its long-lasting masking. While CFS effectively masks static stimuli, its application to motion stimuli remains challenging. To resolve this issue, our previous work developed the Chameleon-1 paradigm (Zhao & Bao, 2022), an enhanced CFS technique that enables robust masking of translational motion stimuli for up to 10s through precise spatiotemporal matching of color dynamics between target and masking stimuli. The current study systematically evaluated and optimized this paradigm through three studies. We first assessed the masking efficacy of the Chameleon-1 paradigm across different motion parameters and patterns (Study 1). Because Chameleon-1 failed to effectively mask biological motion (BM) stimuli, we then upgraded the paradigm to accommodate BM stimulus characteristics (Study 2). The results demonstrated that this Chameleon-2 paradigm achieved superior masking efficacy for BM stimuli, with average breakthrough time extended by over two-fold compared to Chameleon-1 and breakthrough ratios approximately 75% for upright and 45% for inverted BM stimuli during 10-s of BM presentation. We further employed this paradigm to investigate the neural correlates of conscious and unconscious BM processing using functional near-infraredspectroscopy in Study 3. Our work establishes a robust paradigm for sustained masking of BM stimuli and validates its utility in unconscious processing research. We also provide new insights into the neural mechanisms underlying unconscious BM perception.

Similar or opposite? Differences in the recognition of communicative intentions from biological motion in adults with autism and schizophrenia.

ABSTRACTBackground and AimThis study aims to retrospectively assess the point‐light display (PLD) action observation methodology, in order to explore the effect of action observation treatment (AOT) for locomotion rehabilitation in aged patients at risk of falling.MethodsThe results of 30 patients were assessed with 10 patients benefiting from conventional rehabilitation program, 10 patients receiving an AOT program involving the observation of PLD representing a young actor, and 10 patients receiving an AOT program involving the observation of PLD representing an old actor (PLD‐O).ResultsThe analysis revealed more progress for patients who benefited from AOT observation compared to conventional therapy on standardized tests measuring daily life actions (Bartel index) and disability in the lower limbs (Short Physical Performance Battery) but only when PLD represented an old actor.DiscussionThese results suggest that an AOT program involving the observation of PLDs is a promising approach for rehabilitating patients at risk of falling in a clinical context but matching the motor repertoire seems a crucial factor for optimizing the effects.

Highly efficient and thermally stable multifunctional near-infrared emitting phosphors as light source for multiple applications.

Most research on the development of emotion recognition has focused on facial expressions, leaving a relative gap in our understanding of how children interpret emotions through body movements. This study examined developmental changes in the ability to recognize basic emotions (joy, anger, fear, and sadness) from human biological motion presented in point-light displays (HBM-PLDs), with particular attention to how these changes vary depending on the type of emotion and age. One hundred twenty-eight preschool and primary school children aged 4-12 years participated in two experimental tasks involving the explicit recognition of emotions from HBM-PLDs. The results highlight a clear developmental progression in the recognition of emotions from HBM-PLDs with increasing age. This developmental change appears to follow a curvilinear trajectory, with an inflection point around 8.5 years of age (100 months). However, the study further reveals that this inflection point differs depending on the specific discrete emotion considered. Joy seems to be recognized as early as age 4, followed by anger between ages 5 and 6, sadness between ages 6 and 7.5, and finally fear after age 9-10. This represents an important contribution, demonstrating that the improvement in emotion recognition from body movement is not homogeneous but modulated according to the discrete emotion. These findings support the idea that the development of discrete emotion recognition is independent of the modality of presentation (facial expressions, body movements, vocal cues, etc.) and suggest that emotion recognition may rely on a modality-independent and unified developmental process. (PsycInfo Database Record (c) 2026 APA, all rights reserved).

This study investigates how optical information and dynamical constraints influence movement production and perception. In Experiment 1, 16 volunteers walked or performed a Y-balance movement with and without sight on sturdy or foam-padded floors. The optical information and force environment affected the participants’ kinematics, such as stride duration, stride length, stride width, gait speed, joint ranges of motion for walking, total movement duration, and joint ranges of motion for Y-balance. Naïve observers then watched these movements on a point-light display and distinguished movements executed under different optical information (Experiment 2) and force environment (Experiment 3) conditions. They were able to pick out movements performed without sight, especially for those performed on a padded floor; they were also able to discriminate movements performed on different supporting surfaces, especially when the actors were blindfolded. Thus, discriminating movement conditions from point-light displays was possible, and better with higher kinematic variability. Logistic regressions showed discriminating movements relied on the movement kinematics that varied the most between conditions. This information was valid and useful regardless of viewing perspective; that is, whether the walking and Y-balance were displayed in the frontal or side view, the perceptual performance was equivalent. Thus, both optical information and dynamical constraints shape movement patterns in ways that are perceptible through the kinematic variations.

While biological motion processing has been extensively studied, little is known about the top-down impact of expectations in this context. We tested whether expectations about the likelihood of encountering a human walker influence the detection of biological motion in point-light displays, particularly when perceptual information is unreliable. Seventy-four participants completed a signal detection task, responding to stimuli featuring either a human walker or scrambled biological motion, each masked with one of four levels of visual noise. Participants were randomly assigned to the high or low expectations group and were told that 75% or 25% of the displays would feature a human walker, although the actual proportion was 50%. Participants in the high expectation group showed a greater tendency to respond “yes,” with the largest group difference emerging at the highest level of noise. These findings suggest that expectations can bias biological motion detection, particularly under conditions of sensory unreliability. The results also support the predictive processing model of agency detection, which proposes that false-positive perceptions of (supernatural) agents arise from expectations combined with ambiguous input.

Spiking neural network analysis of MT-MST pathways in biological motion processing

Soft electronics based on polymeric gels with unique optical, mechanical and electrical properties are of crucial importance in marine resource exploration. Hydrophobic fluorinated ionogel that combines with optical transparency, flexibility and conductivity is considered a promising potential. However, current soft ionogels struggle to meet the requirements of high electrical conductivity, transparency and perception sensitivity in the aquatic environment. Herein, a novel fluorinated polymeric ionogel is developed incorporated with tert-butyl groups and hydrophobic ionic liquid. Benefiting from the strong supramolecular dipole interaction of fluorine atoms and the hydrogen bond of tert-butyl ester, this designed polymeric ionogel exhibits both high transparency (96.38%) and enhanced ion mobility (1.74 mS cm-1). To further achieve high sensitivity, a suspended 3D morphing mechanism is proposed to construct an underwater camouflage skin with ultra-high underwater sensitivity (≈2.9Pa), which enables capturing flow field gradients, tracking biological motion, and precisely localizing disturbance sources. As a demo, the ionogel-based suspended underwater electronic device is integrated into a dolphin-inspired untethered robot and further showed the closed-loop control capability of danger perception, decision and autonomous avoidance, demonstrating significant promise in underwater bionic electronics and intelligent robotics.

The Advanced Octopus Robotic Arm is a revolutionary. The robotic system was inspired by the flexible and adaptive movement ofan octopus tentacle. Unlike traditional robotic arms that rely onrigid joints, this design incorporates soft robotics principles toachieve multi-directional flexibility, adaptability, and precisecontrol. The arm is usually made with siliconebasedmaterials, pneumatic or hydraulic actuators, and embeddedsensors that mimic biological muscle movement. This bioinspireddesign allows the robotic arm to perform a number of complex tasks, includingGrasping of irregular objects Underwater manipulation and preciseoperations where traditional rigid robots fail. The system is the main difference is that these fans are controlled using advanced algorithms and microcontrollers.Providing real-time motion control, feedback, and stability. Withits combination of soft material design, intelligent control, andadaptability, the advanced octopus robotic arm possesses remarkablymedical surgery, underwater robotics, rescue applicationsoperations, and industrial automation

Bacteria motility is one of the critical bacterial behavior to exploit available resources and environments due to their biological movement toward resources supporting proliferation. Commonly used techniques investigating bacterial motility include cell staining, DNA sequencing, and fluorescent labeling, which are time consuming and challenged by limited markers and subsequent native bacterial cell high information collections. Distinguishing bacteria with high/low motility potential with simple and fast techniques are in demand. Here, a label-free DC-iDEP (Direct-current insulator based dielectrophoresis) based microfluidic device is introduced to detect the motility behavior of Bacillus subtilis. Bacillus subtilis incubated at pH 5, 7, 9 culture medium showed different high/low motility in agar stabbed tests. These bacteria samples with different motilities were used as controls to explore the motility influences on the biophysical characterizations in DC-iDEP. Results indicate the new approach is capable of distinguishing motility changes based on biophysical properties of Bacillus subtilis even before days of bacterial agar tests. The characterization biophysical factor (ratio of electrokinetic to dielectrophoretic mobility, EKMr) of Bacillus subtilis were found to increase as motility increases. Furthermore, andrographolide, a herbal medicine, was found to inhibit the motility behavior and this could be detected by DEP as the characterized biophysical property of andrographolide treated bacteria (5.3 × 109 V/m2) shows significant smaller EKMr than control (9.8 × 109 V/m2). Anti-cBir1-IgG, an anti-bacterial flagellin antibody, was found level increase after andrographolide treatment by the enzyme-linked immunosorbent assay (ELISA). The results indicated that the new approach enables motility detection without the need of time-consuming agar culturing and exhibited possible causes of the convergent movement of bacteria. The microfluidic approach is promising in screening medicines that induce bacteria motility changes contributing to environmental and microbiology studies.

In recent decades, robotics has witnessed exponential growth and widespread application across various domains such as manufacturing, healthcare, agriculture, and civil engineering. However, the significant energy consumption of current robotic systems has become a limitation for robotics. The efficiency movement of animals, which can be used to design and apply in robotics, can help reduce energy consumption. This review explores whether animal movements can contribute to energy savings in robotics. It seeks the existing applications of biological movement principles in robotic systems, analyzes the rationale behind their animal models, and discusses the challenges faced. By studying this paper, it is concluded that the biological movement can save energy and provide insights for the future development of energy-efficient, bio-inspired robotic systems.