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Ayse Pinar Saygin - One of the best experts on this subject based on the ideXlab platform.
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Individual differences in the perception of Biological Motion: links to social cognition and motor imagery.
Cognition, 2013Co-Authors: Luke E. Miller, Ayse Pinar SayginAbstract:Biological Motion perception is often claimed to support social cognition, and to rely upon embodied representations and motor imagery. Are people with higher levels of social traits or more vivid motor imagery better at Biological Motion perception? We administered four experiments measuring sensitivity in using (global) form and (local) Motion cues in Biological Motion, plus well-established measures of social cognition (e.g., empathy) and motor imagery (e.g., kinesthetic motor imagery). This first systematic investigation of individual variability in Biological Motion processing demonstrated significant relationships between these domains, along with a dissociation. Sensitivity for using form cues in Biological Motion processing was correlated with social (and not the imagery) measures; sensitivity for using Motion cues was correlated with motor imagery (and not the social) measures. These results could not be explained by performance on non-Biological control stimuli. We thus show that although both social cognition and motor imagery predict sensitivity to Biological Motion, these skills likely tap into different aspects of perception.
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Neuroanatomical correlates of Biological Motion detection
Neuropsychologia, 2012Co-Authors: Sharon Gilaie-dotan, Ryota Kanai, Bahador Bahrami, Geraint Rees, Ayse Pinar SayginAbstract:Biological Motion detection is both commonplace and important, but there is great inter-individual variability in this ability, the neural basis of which is currently unknown. Here we examined whether the behavioral variability in Biological Motion detection is reflected in brain anatomy. Perceptual thresholds for detection of Biological Motion and control conditions (non-Biological object Motion detection and Motion coherence) were determined in a group of healthy human adults (n=31) together with structural magnetic resonance images of the brain. Voxel based morphometry analyzes revealed that gray matter volumes of left posterior superior temporal sulcus (pSTS) and left ventral premotor cortex (vPMC) significantly predicted individual differences in Biological Motion detection, but showed no significant relationship with performance on the control tasks. Our study reveals a neural basis associated with the inter-individual variability in Biological Motion detection, reliably linking the neuroanatomical structure of left pSTS and vPMC with Biological Motion detection performance.
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normal form from Biological Motion despite impaired ventral stream function
Neuropsychologia, 2011Co-Authors: Geraint Rees, Sharon Gilaiedotan, Shlomo Bentin, Michal Harel, Ayse Pinar SayginAbstract:We explored the extent to which Biological Motion perception depends on ventral stream integration by studying LG, an unusual case of developmental visual agnosia. LG has significant ventral stream processing deficits but no discernable structural cortical abnormality. LG's intermediate visual areas and object-sensitive regions exhibit abnormal activation during visual object perception, in contrast to area V5/MT+ which responds normally to visual Motion (Gilaie-Dotan, Perry, Bonneh, Malach, & Bentin, 2009). Here, in three studies we used point light displays, which require visual integration, in adaptive threshold experiments to examine LG's ability to detect form from Biological and non-Biological Motion cues. LG's ability to detect and discriminate form from Biological Motion was similar to healthy controls. In contrast, he was significantly deficient in processing form from non-Biological Motion. Thus, LG can rely on Biological Motion cues to perceive human forms, but is considerably impaired in extracting form from non-Biological Motion. Finally, we found that while LG viewed Biological Motion, activity in a network of brain regions associated with processing Biological Motion was functionally correlated with his V5/MT+ activity, indicating that normal inputs from V5/MT+ might suffice to activate his action perception system. These results indicate that processing of Biologically moving form can dissociate from other form processing in the ventral pathway. Furthermore, the present results indicate that integrative ventral stream processing is necessary for uncompromised processing of non-Biological form from Motion.
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superior temporal and premotor brain areas necessary for Biological Motion perception
Brain, 2007Co-Authors: Ayse Pinar SayginAbstract:We tested Biological Motion perception in a large group of unilateral stroke patients (N = 60). Both right and left hemisphere lesioned patients were significantly impaired compared with age-matched controls. Voxel-based lesion analyses revealed that lesions in superior temporal and premotor frontal areas had the greatest effect on Biological Motion perception. Moreover, the effect in each region was independent, and not attributable to indirect effects of lesions in the other area. When we explored functional magnetic resonance imaging (fMRI) data collected from neurologically healthy controls in a separate experiment in relation to the lesion maps, we found that the two methods converged on their findings. We thus establish that superior temporal and premotor areas are not only involved in Biological Motion perception, but also have causal relationships to deficits in Biological Motion perception. While the precise functional roles of each region remain to be identified, this network has been implicated in the perception of action stimuli in many studies and as such patients' deficits may reflect an inability to effectively engage the action observation system.
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point light Biological Motion perception activates human premotor cortex
The Journal of Neuroscience, 2004Co-Authors: Ayse Pinar Saygin, Stephen M Wilson, Donald J Hagler, Elizabeth Bates, Martin I SerenoAbstract:Motion cues can be surprisingly powerful in defining objects and events. Specifically, a handful of point-lights attached to the joints of a human actor will evoke a vivid percept of action when the body is in Motion. The perception of point-light Biological Motion activates posterior cortical areas of the brain. On the other hand, observation of others' actions is known to also evoke activity in motor and premotor areas in frontal cortex. In the present study, we investigated whether point-light Biological Motion animations would lead to activity in frontal cortex as well. We performed a human functional magnetic resonance imaging study on a high-field-strength magnet and used a number of methods to increase signal, as well as cortical surface-based analysis methods. Areas that responded selectively to point-light Biological Motion were found in lateral and inferior temporal cortex and in inferior frontal cortex. The robust responses we observed in frontal areas indicate that these stimuli can also recruit action observation networks, although they are very simplified and characterize actions by Motion cues alone. The finding that even point-light animations evoke activity in frontal regions suggests that the motor system of the observer may be recruited to "fill in" these simplified displays.
Markus Lappe - One of the best experts on this subject based on the ideXlab platform.
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Concurrent processing of optic flow and Biological Motion.
Journal of experimental psychology. General, 2019Co-Authors: Katja M. Mayer, Hugh Riddell, Markus LappeAbstract:The concurrent processing of optic flow and Biological Motion is crucial for navigating to a destination without colliding with others. Neuroimaging studies and formal models have provided evidence for distinct neural mechanisms involved in processing the 2 types of Motion. It may, therefore, be possible to process both types of Motions independently. To test for possible interferences at the behavioral level, we conducted a dual task paradigm in which we presented a point-light walker in a flow field that simulated forward Motion. Observers judged both the articulation of the walker and the heading direction. We found that varying the difficulty of one task had no effect on the performance of the other task, arguing against interferences. Performance in the Biological Motion task was similar in dual and single task conditions. For the heading task, concurrence costs were observed when the heading task was difficult but not when it was easy. Concurrence costs did not depend on practice effects, effects of specific motor responses, and incidental processing of Biological Motion. In line with neuroimaging studies and formal models, our results argue not only for independent processing of optic flow and Biological Motion but also for concurrence costs affecting heading performance. (PsycINFO Database Record (c) 2019 APA, all rights reserved).
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Perception of Biological Motion as Motion-from-form
E-neuroforum, 2012Co-Authors: Markus LappeAbstract:The recognition of the movements and actions of others is of great importance for social interaction. The visual Motion pattern projected on the retina when watching somebody else act is called Biological Motion. Because of the many degrees of freedom of the body, Biological Motion is a relatively complicated Motion pattern, much more variable, for example, than optic flow or object Motion. The regularities of Biological Motion are contained in its relationship to the body, i.e. in the constraints imposed by the articulation of the limbs on the movement of the body parts. The neural mechanisms of Biological Motion perception, therefore, take body form information into account. I describe a model of Biological Motion perception that starts from a representation of body form and posture and retrieves Biological Motion as the transformation of the body posture over time. Essentially, this proposes a ventral pathway to Motion perception that is distinct from the other Motion pathways in the dorsal stream, and specialized for body Motion.
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perception of Biological Motion in visual agnosia
Frontiers in Behavioral Neuroscience, 2012Co-Authors: Elisabeth Huberle, Paul Rupek, Markus Lappe, Hans-otto KarnathAbstract:Over the past twenty-five years, visual processing has been discussed in the context of the dual stream hypothesis consisting of a ventral (‘what') and a dorsal ('where') visual information processing pathway. Patients with brain damage of the ventral pathway typically present with signs of visual agnosia, the inability to identify and discriminate objects by visual exploration, but show normal perception of Motion perception. A dissociation between the perception of Biological Motion and non-Biological Motion has been suggested: Perception of Biological Motion might be impaired when 'non-Biological' Motion perception is intact and vice versa. The impact of object recognition on the perception of Biological Motion remains unclear. We thus investigated this question in a patient with severe visual agnosia, who showed normal perception of non-Biological Motion. The data suggested that the patient's perception of Biological Motion remained largely intact. However, when tested with objects constructed of coherently moving dots (‘Shape-from-Motion’), recognition was severely impaired. The results are discussed in the context of possible mechanisms of Biological Motion perception.
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Dynamic Form Templates Determine Sensitivity to Biological Motion
Advances in Cognitive Neurodynamics (II), 2010Co-Authors: Joachim Lange, Markus LappeAbstract:Visual perception of Biological Motion shows a remarkable robustness against noise, fundamentally different from sensitivity to other moving stimuli. This is evidence for especialized mechanisms for Biological Motion perception that are more sensitive to Biological Motion than to other stimuli. Yet, the specifics of Biological Motion stimuli or the mechanisms which might explain the qualitative discrepancy between coherent Motion and Biological Motion in terms of sensitivity remain elusive. In a combination of neurocomputational modeling and psychophysical experiments we investigated how form and Motion signals influence sensitivity to Biological Motion in noise. With stimuli that vary in the amount of Motion signals we tested the ability to detect and discriminate Biological Motion in human observers and in a dynamic neuro-cognitive model of Biological Motion perception. These results suggest that the sensitivity to human movements is caused by a specialization to the dynamic and complex pattern of the changing form of the body over time.
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Bistable Alternation of Point-Light Biological Motion
Advances in Cognitive Neurodynamics (II), 2010Co-Authors: Marc H. E. De Lussanet, Markus LappeAbstract:The facing-in-depth of point-light Biological Motion is ambiguous: the frontal and back view look the same. However, since earlier studies found a very strong perceptual bias in point-light Biological Motion, it is unknown whether it evokes an alternating (bistable) percept. In the present study, naive, untrained observers viewed point-light stimuli in half-profile view. All participants experienced spontaneous flipping of the orientation-in-depth, both for Biological Motion and necker cube displays. The number of perceptual flips was lower for the rocking cube than for the static one; and higher for Biological Motion than for rocking cubes. Contrary to earlier findings the participants did not have a perceptual bias. We conclude that ambiguous Biological Motion does evoke a bistable percept.
Randolph Blake - One of the best experts on this subject based on the ideXlab platform.
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The efficiency of Biological Motion perception.
Perception & psychophysics, 2008Co-Authors: Jason M. Gold, Duje Tadin, Susan C. Cook, Randolph BlakeAbstract:Humans can readily perceive Biological Motion from point-light (PL) animations, which create an image of a moving human figure by tracing the trajectories of a small number of light points affixed to a moving human body. We have applied ideal observer analysis to a standard Biological Motion discrimination task involving either full-figure or PL displays. Contrary to current dogma, we find that PL animations can be rich in potential stimulus information but that human observers are remarkably inefficient at exploiting this information. Although our findings do not discount the utility of PL animation, they do provide a realistic measure of the computational challenge posed by Biological Motion perception.
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The Development of Sensitivity to Biological Motion in Noise
Perception, 2006Co-Authors: Alejo Freire, Terri L. Lewis, Daphne Maurer, Randolph BlakeAbstract:We investigated developmental changes in sensitivity to Biological Motion by asking 6-year-olds, 9-year-olds, and adults (twenty-four in each group) to discriminate point-light Biological Motion displays depicting one of a variety of human movements from scrambled versions of the same displays. When tested without noise dots, participants at all ages performed near ceiling levels and no differences in accuracy were found among the three age groups. Age differences emerged in the second task, in which we used a staircase procedure to determine threshold values of the number of noise dots that could be tolerated in producing a percentage correct value corresponding to a d' value of 1.4. Sensitivity to Biological Motion improved linearly with age (p < 0.01), with 6-year-olds performing significantly more poorly than adults. This immature performance contrasts with adult-like accuracy by 4 years of age for sensitivity to global Motion (Parrish et al, 2005 Vision Research 45 827-837). The comparison implies an immaturity at 6 years of age in the neural networks involved specifically in the processing of Biological Motion, networks that may include the superior temporal sulcus (STS).
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Impaired visual recognition of Biological Motion in schizophrenia.
Schizophrenia research, 2005Co-Authors: Jejoong Kim, Randolph Blake, Mikisha L Doop, Sohee ParkAbstract:Motion perception deficits have been suggested to be an important feature of schizophrenia but the behavioral consequences of such deficits are unknown. Biological Motion refers to the movements generated by living beings. The human visual system rapidly and effortlessly detects and extracts socially relevant information from Biological Motion. A deficit in Biological Motion perception may have significant consequences for detecting and interpreting social information. Schizophrenia patients and matched healthy controls were tested on two visual tasks: recognition of human activity portrayed in point-light animations (Biological Motion task) and a perceptual control task involving detection of a grouped figure against the background noise (global-form task). Both tasks required detection of a global form against background noise but only the Biological Motion task required the extraction of Motion-related information. Schizophrenia patients performed as well as the controls in the global-form task, but were significantly impaired on the Biological Motion task. In addition, deficits in Biological Motion perception correlated with impaired social functioning as measured by the Zigler social competence scale [Zigler, E., Levine, J. (1981). Premorbid competence in schizophrenia: what is being measured? Journal of Consulting and Clinical Psychology, 49, 96-105.]. The deficit in Biological Motion processing, which may be related to the previously documented deficit in global Motion processing, could contribute to abnormal social functioning in schizophrenia.
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Impaired visual recognition of Biological Motion in schizophrenia.
Schizophrenia Research, 2005Co-Authors: Jejoong Kim, Randolph Blake, Mikisha L Doop, Sohee ParkAbstract:Abstract Background Motion perception deficits have been suggested to be an important feature of schizophrenia but the behavioral consequences of such deficits are unknown. Biological Motion refers to the movements generated by living beings. The human visual system rapidly and effortlessly detects and extracts socially relevant information from Biological Motion. A deficit in Biological Motion perception may have significant consequences for detecting and interpreting social information. Methods Schizophrenia patients and matched healthy controls were tested on two visual tasks: recognition of human activity portrayed in point–light animations (Biological Motion task) and a perceptual control task involving detection of a grouped figure against the background noise (global-form task). Both tasks required detection of a global form against background noise but only the Biological Motion task required the extraction of Motion-related information. Results Schizophrenia patients performed as well as the controls in the global-form task, but were significantly impaired on the Biological Motion task. In addition, deficits in Biological Motion perception correlated with impaired social functioning as measured by the Zigler social competence scale [Zigler, E., Levine, J. (1981). Premorbid competence in schizophrenia: what is being measured? Journal of Consulting and Clinical Psychology, 49, 96–105.]. Conclusion The deficit in Biological Motion processing, which may be related to the previously documented deficit in global Motion processing, could contribute to abnormal social functioning in schizophrenia.
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Eccentric perception of Biological Motion is unscalably poor.
Vision research, 2005Co-Authors: Hanako Ikeda, Randolph Blake, Katsumi WatanabeAbstract:Abstract Accurately perceiving the activities of other people is a crucially important social skill of obvious survival value. Human vision is equipped with highly sensitive mechanisms for recognizing activities performed by others [Johansson, G. (1973). Visual perception of Biological Motion and a model for its analysis. Perception and Psychophysics, 14, 201; Johansson, G. (1976). Spatio-temporal differentiation and integration in visual Motion perception: An experimental and theoretical analysis of calculus-like functions in visual data processing. Psychological Research, 38, 379]. One putative functional role of Biological Motion perception is to register the presence of Biological events anywhere within the visual field, not just within central vision. To assess the salience of Biological Motion throughout the visual field, we compared the detectability performances of Biological Motion animations imaged in central vision and in peripheral vision. To compensate for the poorer spatial resolution within the periphery, we spatially magnified the Motion tokens defining Biological Motion. Normal and scrambled Biological Motion sequences were embedded in Motion noise and presented in two successively viewed intervals on each trial (2AFC). Subjects indicated which of the two intervals contained normal Biological Motion. A staircase procedure varied the number of noise dots to produce a criterion level of discrimination performance. For both foveal and peripheral viewing, performance increased but saturated with stimulus size. Foveal and peripheral performance could not be equated by any magnitude of size scaling. Moreover, the inversion effect––superiority of upright over inverted Biological Motion [Sumi, S. (1984). Upside-down presentation of the Johansson moving light-spot pattern. Perception, 13, 283]––was found only when animations were viewed within the central visual field. Evidently the neural resource responsible for Biological Motion perception are embodied within neural mechanisms focused on central vision.
Nikolaus F. Troje - One of the best experts on this subject based on the ideXlab platform.
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Does belief in free will influence Biological Motion perception?
2021Co-Authors: Wei Peng, Nikolaus F. Troje, Emiel Cracco, Marcel BrassAbstract:Previous research suggests that belief in free will correlates positively with intention perception. However, whether belief in free will is also related to more basic social processes is unknown. Based on evidence that Biological Motion is an intention-carrier, we investigate if belief in free will and related two beliefs, namely belief in dualism and belief in determinism, are associated with Biological Motion perception. Signal Detection Theory (SDT) was used to measure participants’ ability to detect Biological Motion from scrambled background noise (d') and their response bias (c) in doing so. In two experiments, we found that belief in determinism and belief in dualism, but not belief in free will, were associated with the perception of Biological Motion. However, no causal relationship was found when experimentally manipulating free will-related beliefs. In general, our research suggests that basic social processes, like Biological Motion perception, can be predicted by high-level beliefs.
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Spatiotemporal dynamics of responses to Biological Motion in the human brain
Cortex; a journal devoted to the study of the nervous system and behavior, 2021Co-Authors: Dorita H. F. Chang, Nikolaus F. Troje, Yuji Ikegaya, Ichiro Fujita, Hiroshi BanAbstract:Abstract We sought to understand the spatiotemporal characteristics of Biological Motion perception. We presented observers with Biological Motion walkers that differed in terms of form coherence or kinematics (i.e., the presence or absence of natural acceleration). Participants were asked to discriminate the facing direction of the stimuli while their magnetoencephalographic responses were concurrently imaged. We found that two univariate response components can be observed around ∼200 ms and ∼650 ms post-stimulus onset, each engaging lateral-occipital and parietal cortex prior to temporal and frontal cortex. Moreover, while univariate responses show Biological Motion form-specificity only after 300 ms, multivariate patterns specific to form can be well discriminated from those for local cues as early as 100 ms after stimulus onset. By finally examining the representational similarity of fMRI and MEG patterned responses, we show that early responses to Biological Motion are most likely sourced to occipital cortex while later responses likely originate from extrastriate body areas.
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Cortical and subcortical responses to Biological Motion.
NeuroImage, 2018Co-Authors: Dorita H. F. Chang, Hiroshi Ban, Yuji Ikegaya, Ichiro Fujita, Nikolaus F. TrojeAbstract:Abstract Using fMRI and multivariate analyses we sought to understand the neural representations of articulated body shape and local kinematics in Biological Motion. We show that in addition to a cortical network that includes areas identified previously for Biological Motion perception, including the posterior superior temporal sulcus, inferior frontal gyrus, and ventral body areas, the ventral lateral nucleus, a presumably motoric thalamic area is sensitive to both form and kinematic information in Biological Motion. Our findings suggest that Biological Motion perception is not achieved as an end-point of segregated cortical form and Motion networks as often suggested, but instead involves earlier parts in the visual system including a subcortical network.
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A test battery for assessing Biological Motion perception
Journal of Vision, 2011Co-Authors: Daniel R. Saunders, Nikolaus F. TrojeAbstract:Biological Motion perception is often assessed using a single task. However, it was shown that there are at least two distinct processes at work, one based on local Motion information and one based on integrating information about the structure across the display (Troje and Westhoff, 2006). Along with other recent results, this suggests that Biological Motion is analyzed via a hierarchy of perceptual abilities, including:
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IQ predicts Biological Motion perception in autism spectrum disorders.
Journal of autism and developmental disorders, 2011Co-Authors: M. D. Rutherford, Nikolaus F. TrojeAbstract:Biological Motion is easily perceived by neurotypical observers when encoded in point-light displays. Some but not all relevant research shows significant deficits in Biological Motion perception among those with ASD, especially with respect to eMotional displays. We tested adults with and without ASD on the perception of masked Biological Motion and the perception of direction from coherent and scrambled Biological Motion. Within the autism spectrum group, there was a large and statistically significant relationship between IQ and the ability to perceive directionality in masked Biological Motion. There were no group differences in sensitivity to Biological Motion or the ability to identify the direction of Motion. Possible explanations are discussed, including the possible use of compensatory strategies in high IQ ASD.
Yi Jiang - One of the best experts on this subject based on the ideXlab platform.
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Developmental tuning of reflexive attentional effect to Biological Motion cues.
Scientific reports, 2014Co-Authors: Jing Zhao, Li Wang, Ying Wang, Xuchu Weng, Yi JiangAbstract:The human visual system is extremely sensitive to the direction information retrieved from Biological Motion. In the current study, we investigate the functional impact of this sensitivity on attentional orienting in young children. We found that children as early as 4 years old, like adults, showed a robust reflexive attentional orienting effect to the walking direction of an upright point-light walker, indicating that Biological Motion signals can automatically direct spatial attention at an early age. More importantly, the inversion effect associated with attentional orienting emerges by 4 years old and gradually develops into a similar pattern found in adults. These results provide strong evidence that Biological Motion cues can guide the distribution of spatial attention in young children, and highlight a critical development from a broadly- to finely-tuned process of utilizing Biological Motion cues in the human social brain.
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Biological Motion cues trigger reflexive attentional orienting
Cognition, 2010Co-Authors: Jinfu Shi, Xuchu Weng, Yi JiangAbstract:The human visual system is extremely sensitive to Biological signals around us. In the current study, we demonstrate that Biological Motion walking direction can induce robust reflexive attentional orienting. Following a brief presentation of a central point-light walker walking towards either the left or right direction, observers' performance was significantly better on a target in the walking direction compared with that in the opposite direction even when participants were explicitly told that walking direction was not predictive of target location. Interestingly, the effect disappeared when the walker was shown upside-down. Moreover, the reflexive attentional orienting could be extended to Motions of other Biological entities but not inanimate objects, and was not due to the viewpoint effect of the point-light figure. Our findings provide strong evidence that Biological Motion cues can trigger reflexive attentional orienting, and highlight the intrinsic sensitivity of the human visual attention system to Biological signals.