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Journal of Neuroengineering and... Dec 2015Quantitative measures of smoothness play an important role in the assessment of sensorimotor impairment and motor learning. Traditionally, movement smoothness has been... (Review)
Review
Quantitative measures of smoothness play an important role in the assessment of sensorimotor impairment and motor learning. Traditionally, movement smoothness has been computed mainly for discrete movements, in particular arm, reaching and circle drawing, using kinematic data. There are currently very few studies investigating smoothness of rhythmic movements, and there is no systematic way of analysing the smoothness of such movements. There is also very little work on the smoothness of other movement related variables such as force, impedance etc. In this context, this paper presents the first step towards a unified framework for the analysis of smoothness of arbitrary movements and using various data. It starts with a systematic definition of movement smoothness and the different factors that influence smoothness, followed by a review of existing methods for quantifying the smoothness of discrete movements. A method is then introduced to analyse the smoothness of rhythmic movements by generalising the techniques developed for discrete movements. We finally propose recommendations for analysing smoothness of any general sensorimotor behaviour.
Topics: Biomechanical Phenomena; Electrophysiology; Humans; Movement
PubMed: 26651329
DOI: 10.1186/s12984-015-0090-9 -
International Journal of... Feb 2012Agency is an important aspect of bodily self-consciousness, allowing us to separate own movements from those induced by the environment and to distinguish own movements... (Review)
Review
Agency is an important aspect of bodily self-consciousness, allowing us to separate own movements from those induced by the environment and to distinguish own movements from those of other agents. Unsurprisingly, theoretical frameworks for agency such as central monitoring are closely tied to computational models of sensorimotor control. Until recently agency research has largely focussed on goal-directed movements of the upper limbs. In particular, the influence of performance-related sensory cues and the relevance of prediction signals for agency judgements have been studied through a variety of spatio-temporal mismatches between movement and the sensory consequences of movement. However, agents often perform a different type of movement; highly automated movements that involve the entire body such as walking, cycling, and swimming with potentially different agency mechanisms. Here, we review recent work about agency for full-body movements such as gait, highlighting the effects of performance-related visual and auditory cues on gait agency. Gait movements differ from upper limb actions. Gait is cyclic, more rarely immediately goal-directed, and is generally considered one of the most automatic and unconscious actions. We discuss such movement differences with respect to the functional mechanisms of full-body agency and body-part agency by linking these gait agency paradigms to computational models of motor control. This is followed by a selective review of gait control, locomotion, and models of motor control relying on prediction signals and underlining their relevance for full-body agency.
Topics: Acoustic Stimulation; Animals; Awareness; Consciousness; Gait; Humans; Motor Activity; Photic Stimulation; Psychomotor Performance; Walking
PubMed: 22226801
DOI: 10.1016/j.ijpsycho.2011.12.006 -
Experimental Brain Research Sep 2013Neurological disorders of volition may be characterized by deficits in willing and/or agency. When we move our bodies through space, it is the sense that we intended to... (Review)
Review
Neurological disorders of volition may be characterized by deficits in willing and/or agency. When we move our bodies through space, it is the sense that we intended to move (willing) and that our actions were a consequence of this intention (self-agency) that gives us the sense of voluntariness and a general feeling of being "in control." While it is possible to have movements that share executive machinery ordinarily used for voluntary movement but lack a sense of voluntariness, such as psychogenic movement disorders, it is also possible to claim volition for presumed involuntary movements (early chorea) or even when no movement is produced (anosognosia). The study of such patients should enlighten traditional models of how the percepts of volition are generated in the brain with regard to movement. We discuss volition and its components as multi-leveled processes with feedforward and feedback information flow, and dependence on prior expectations as well as external and internal cues.
Topics: Agnosia; Brain; Humans; Intention; Movement; Volition
PubMed: 23329204
DOI: 10.1007/s00221-013-3399-2 -
Journal of Parkinson's Disease 2022Parkinson's disease (PD) is known to affect the brain motor circuits involving the basal ganglia (BG) and to induce, among other signs, general slowness and paucity of... (Review)
Review
Parkinson's disease (PD) is known to affect the brain motor circuits involving the basal ganglia (BG) and to induce, among other signs, general slowness and paucity of movements. In upper limb movements, PD patients show a systematic prolongation of movement duration while maintaining a sufficient level of endpoint accuracy. PD appears to cause impairments not only in movement execution, but also in movement initiation and planning, as revealed by abnormal preparatory activity of motor-related brain areas. Grasping movement is affected as well, particularly in the coordination of the hand aperture with the transport phase. In the last fifty years, numerous behavioral studies attempted to clarify the mechanisms underlying these anomalies, speculating on the plausible role that the BG-thalamo-cortical circuitry may play in normal and pathological motor control. Still, many questions remain open, especially concerning the management of the speed-accuracy tradeoff and the online feedback control. In this review, we summarize the literature results on reaching and grasping in parkinsonian patients. We analyze the relevant hypotheses on the origins of dysfunction, by focusing on the motor control aspects involved in the different movement phases and the corresponding role played by the BG. We conclude with an insight into the innovative stimulation techniques and computational models recently proposed, which might be helpful in further clarifying the mechanisms through which PD affects reaching and grasping movements.
Topics: Basal Ganglia; Hand; Humans; Motor Cortex; Movement; Parkinson Disease; Psychomotor Performance
PubMed: 35253780
DOI: 10.3233/JPD-213082 -
Canadian Medical Association Journal May 1966The development of bipedal plantigrade progression is a purely human, and apparently learned, accomplishment. Experimental findings confirm the hypothesis that the human...
The development of bipedal plantigrade progression is a purely human, and apparently learned, accomplishment. Experimental findings confirm the hypothesis that the human body will integrate the motion of various segments of the body and control the activity of muscles to minimize energy expenditure.Movements which are integrated for this purpose include vertical displacement of the body, horizontal rotation of the pelvis, mediolateral pelvic tilt, flexion of the knee, plantar flexion of the ankle and foot, lateral displacement of the torso and rotation of the shoulder girdle.Raising and lowering the body results in gains and losses of potential energy, and acceleration and deceleration result in gains and losses of kinetic energy. The motions are so co-ordinated that a transfer of energy back and forth from kinetic to potential occurs during walking, which tends to minimize total energy expenditure as well as muscle work.
Topics: Humans; Kinetics; Locomotion; Motor Skills; Movement
PubMed: 5942660
DOI: No ID Found -
Attention, Perception & Psychophysics Oct 2021Examining eye-movement behavior during visual search is an increasingly popular approach for gaining insights into the moment-to-moment processing that takes place when... (Review)
Review
Examining eye-movement behavior during visual search is an increasingly popular approach for gaining insights into the moment-to-moment processing that takes place when we look for targets in our environment. In this tutorial review, we describe a set of pitfalls and considerations that are important for researchers - both experienced and new to the field - when engaging in eye-movement and visual search experiments. We walk the reader through the research cycle of a visual search and eye-movement experiment, from choosing the right predictions, through to data collection, reporting of methodology, analytic approaches, the different dependent variables to analyze, and drawing conclusions from patterns of results. Overall, our hope is that this review can serve as a guide, a talking point, a reflection on the practices and potential problems with the current literature on this topic, and ultimately a first step towards standardizing research practices in the field.
Topics: Eye Movements; Humans; Movement
PubMed: 34089167
DOI: 10.3758/s13414-021-02326-w -
Computers in Biology and Medicine Apr 2020Recent advances in data analytics and computer-aided diagnostics stimulate the vision of patient-centric precision healthcare, where treatment plans are customized based... (Review)
Review
Recent advances in data analytics and computer-aided diagnostics stimulate the vision of patient-centric precision healthcare, where treatment plans are customized based on the health records and needs of every patient. In physical rehabilitation, the progress in machine learning and the advent of affordable and reliable motion capture sensors have been conducive to the development of approaches for automated assessment of patient performance and progress toward functional recovery. The presented study reviews computational approaches for evaluating patient performance in rehabilitation programs using motion capture systems. Such approaches will play an important role in supplementing traditional rehabilitation assessment performed by trained clinicians, and in assisting patients participating in home-based rehabilitation. The reviewed computational methods for exercise evaluation are grouped into three main categories: discrete movement score, rule-based, and template-based approaches. The review places an emphasis on the application of machine learning methods for movement evaluation in rehabilitation. Related work in the literature on data representation, feature engineering, movement segmentation, and scoring functions is presented. The study also reviews existing sensors for capturing rehabilitation movements and provides an informative listing of pertinent benchmark datasets. The significance of this paper is in being the first to provide a comprehensive review of computational methods for evaluation of patient performance in rehabilitation programs.
Topics: Exercise; Exercise Therapy; Humans; Movement
PubMed: 32339122
DOI: 10.1016/j.compbiomed.2020.103687 -
The Journal of Neuroscience : the... Aug 2022The ability to perform skilled arm movements is central to everyday life, as limb impairments in common neurologic disorders such as stroke demonstrate. Skilled arm...
The ability to perform skilled arm movements is central to everyday life, as limb impairments in common neurologic disorders such as stroke demonstrate. Skilled arm movements require adaptation of motor commands based on discrepancies between desired and actual movements, called sensory errors. Studies in humans show that this involves predictive and reactive movement adaptations to the errors, and also requires a general motivation to move. How these distinct aspects map onto defined neural signals remains unclear, because of a shortage of equivalent studies in experimental animal models that permit neural-level insights. Therefore, we adapted robotic technology used in human studies to mice, enabling insights into the neural underpinnings of motivational, reactive, and predictive aspects of motor adaptation. Here, we show that forelimb motor adaptation is regulated by neurons previously implicated in motivation and arousal, but not in forelimb motor control: the hypothalamic orexin/hypocretin neurons (HONs). By studying goal-oriented mouse-robot interactions in male mice, we found distinct HON signals occur during forelimb movements and motor adaptation. Temporally-delimited optosilencing of these movement-associated HON signals impaired sensory error-based motor adaptation. Unexpectedly, optosilencing affected neither task reward or execution rates, nor motor performance in tasks that did not require adaptation, indicating that the temporally-defined HON signals studied here were distinct from signals governing general task engagement or sensorimotor control. Collectively, these results reveal a hypothalamic neural substrate regulating forelimb motor adaptation. The ability to perform skilled, adaptable movements is a fundamental part of daily life, and is impaired in common neurologic diseases such as stroke. Maintaining motor adaptation is thus of great interest, but the necessary brain components remain incompletely identified. We found that impaired motor adaptation results from disruption of cells not previously implicated in this pathology: hypothalamic orexin/hypocretin neurons (HONs). We show that temporally confined HON signals are associated with skilled movements. Without these newly-identified signals, a resistance to movement that is normally rapidly overcome leads to prolonged movement impairment. These results identify natural brain signals that enable rapid and effective motor adaptation.
Topics: Animals; Forelimb; Humans; Male; Mice; Movement; Orexins; Stroke; Upper Extremity
PubMed: 35790405
DOI: 10.1523/JNEUROSCI.0705-22.2022 -
Assistive Technology : the Official... 2011Individuals who rely on augmentative and alternative communication (AAC) devices to support their communication often have physical movement challenges that require...
Individuals who rely on augmentative and alternative communication (AAC) devices to support their communication often have physical movement challenges that require alternative methods of access. Technology that supports access, particularly for those with the most severe movement deficits, have expanded substantially over the years. The purposes of this article are to review the state of the science of access technologies that interface with augmentative and alternative communication devices and to propose a future research and development agenda that will enhance access options for people with limited movement capability due to developmental and acquired conditions.
Topics: Communication Aids for Disabled; Eye Movements; Gestures; Head Movements; Humans; Motor Skills; User-Computer Interface
PubMed: 22590797
DOI: 10.1080/10400435.2011.648712 -
Tracking and Classification of Head Movement for Augmentative and Alternative Communication Systems.Sensors (Basel, Switzerland) Jan 2022The use of assistive technologies can mitigate or reduce the challenges faced by individuals with motor disabilities to use computer systems. However, those who feature...
The use of assistive technologies can mitigate or reduce the challenges faced by individuals with motor disabilities to use computer systems. However, those who feature severe involuntary movements often have fewer options at hand. This work describes an application that can recognize the user's head using a conventional webcam, track its motion, model the desired functional movement, and recognize it to enable the use of a virtual keyboard. The proposed classifier features a flexible structure and may be personalized for different user need. Experimental results obtained with participants with no neurological disorders have shown that classifiers based on Hidden Markov Models provided similar or better performance than a classifier based on position threshold. However, motion segmentation and interpretation modules were sensitive to involuntary movements featured by participants with cerebral palsy that took part in the study.
Topics: Cerebral Palsy; Communication; Head Movements; Humans; Movement; Self-Help Devices; User-Computer Interface
PubMed: 35062395
DOI: 10.3390/s22020435