1
|
Okuuchi S, Tani K, Kushiro K. Temporal properties of the speed-accuracy trade-off for arm-pointing movements in various directions around the body. PLoS One 2023; 18:e0291715. [PMID: 37733687 PMCID: PMC10513193 DOI: 10.1371/journal.pone.0291715] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2023] [Accepted: 09/04/2023] [Indexed: 09/23/2023] Open
Abstract
Human body movements are based on the intrinsic trade-off between speed and accuracy. Fitts's law (1954) shows that the time required for movement is represented by a simple logarithmic equation and is applicable to a variety of movements. However, few studies have determined the role of the direction in modulating the performance of upper limb movements and the effects of the interactions between direction and distance and between direction and target size. This study examined the variations in temporal properties of the speed-accuracy trade-off in arm-pointing movements that directly manipulate objects according to the direction, distance, and target size. Participants performed pointing movements to the targets with 3 different sizes presented at 15 locations (5 directions and 3 distances) on a horizontal plane. Movement time (MT) for each trial in each condition was obtained. Subsequently, Mackenzie's model (1992), MT = a + b log2(D/W +1), where D and W represent the distance and width of the target, respectively, was fitted. The slope factor b, a fitted parameter in the equation, was calculated and evaluated according to the changes in the direction, distance, and target size. The results showed that MTs exhibited anisotropy in the hemifield, being the smallest in the right-forward direction. Additionally, the slope factor b, as a function of distance, was smaller in the rightward direction than in the forward and left-forward directions. These results suggest that the degree of difficulty of upper limb movements expands heterogeneously in various directions around the body.
Collapse
Affiliation(s)
- Soma Okuuchi
- Graduate School of Human and Environment Studies, Kyoto University, Kyoto, Japan
| | - Keisuke Tani
- Graduate School of Human and Environment Studies, Kyoto University, Kyoto, Japan
- Faculty of Psychology, Otemon Gakuin University, Osaka, Japan
| | - Keisuke Kushiro
- Graduate School of Human and Environment Studies, Kyoto University, Kyoto, Japan
| |
Collapse
|
2
|
Torricelli F, Tomassini A, Pezzulo G, Pozzo T, Fadiga L, D'Ausilio A. Motor invariants in action execution and perception. Phys Life Rev 2023; 44:13-47. [PMID: 36462345 DOI: 10.1016/j.plrev.2022.11.003] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2022] [Accepted: 11/21/2022] [Indexed: 11/27/2022]
Abstract
The nervous system is sensitive to statistical regularities of the external world and forms internal models of these regularities to predict environmental dynamics. Given the inherently social nature of human behavior, being capable of building reliable predictive models of others' actions may be essential for successful interaction. While social prediction might seem to be a daunting task, the study of human motor control has accumulated ample evidence that our movements follow a series of kinematic invariants, which can be used by observers to reduce their uncertainty during social exchanges. Here, we provide an overview of the most salient regularities that shape biological motion, examine the role of these invariants in recognizing others' actions, and speculate that anchoring socially-relevant perceptual decisions to such kinematic invariants provides a key computational advantage for inferring conspecifics' goals and intentions.
Collapse
Affiliation(s)
- Francesco Torricelli
- Department of Neuroscience and Rehabilitation, University of Ferrara, Via Fossato di Mortara, 17-19, 44121 Ferrara, Italy; Center for Translational Neurophysiology of Speech and Communication, Italian Institute of Technology, Via Fossato di Mortara, 17-19, 44121 Ferrara, Italy
| | - Alice Tomassini
- Center for Translational Neurophysiology of Speech and Communication, Italian Institute of Technology, Via Fossato di Mortara, 17-19, 44121 Ferrara, Italy
| | - Giovanni Pezzulo
- Institute of Cognitive Sciences and Technologies, National Research Council, Via San Martino della Battaglia 44, 00185 Rome, Italy
| | - Thierry Pozzo
- Center for Translational Neurophysiology of Speech and Communication, Italian Institute of Technology, Via Fossato di Mortara, 17-19, 44121 Ferrara, Italy; INSERM UMR1093-CAPS, UFR des Sciences du Sport, Université Bourgogne Franche-Comté, F-21000, Dijon, France
| | - Luciano Fadiga
- Department of Neuroscience and Rehabilitation, University of Ferrara, Via Fossato di Mortara, 17-19, 44121 Ferrara, Italy; Center for Translational Neurophysiology of Speech and Communication, Italian Institute of Technology, Via Fossato di Mortara, 17-19, 44121 Ferrara, Italy
| | - Alessandro D'Ausilio
- Department of Neuroscience and Rehabilitation, University of Ferrara, Via Fossato di Mortara, 17-19, 44121 Ferrara, Italy; Center for Translational Neurophysiology of Speech and Communication, Italian Institute of Technology, Via Fossato di Mortara, 17-19, 44121 Ferrara, Italy.
| |
Collapse
|
3
|
Fiorio M, Villa-Sánchez B, Rossignati F, Emadi Andani M. The placebo effect shortens movement time in goal-directed movements. Sci Rep 2022; 12:19567. [PMID: 36380087 PMCID: PMC9666443 DOI: 10.1038/s41598-022-23489-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2022] [Accepted: 11/01/2022] [Indexed: 11/16/2022] Open
Abstract
The placebo effect is a powerful psychobiological phenomenon whereby a positive outcome follows the administration of an inert treatment thought to be effective. Growing evidence shows that the placebo effect extends beyond the healing context, affecting also motor performance. Here we explored the placebo effect on the control of goal-directed movement, a fundamental function in many daily activities. Twenty-four healthy volunteers performed upper-limb movements toward a target at different indexes of difficulty in two conditions: in the placebo condition, an electrical device (inert) was applied to the right forearm together with verbal information about its positive effects in improving movement precision; in the control condition, the same device was applied along with verbal information about its neutral effects on performance. Interestingly, we found shorter movement time in the placebo compared to the control condition. Moreover, subjective perception of fatigability was reduced in the placebo compared to the control condition. These findings indicate that the placebo effect can improve the execution of goal-directed movements, thus adding new evidence to the placebo effect in the motor domain. This study could inspire future applications to improve upper-limb movements or in clinical settings for patients with motor deficits.
Collapse
Affiliation(s)
- Mirta Fiorio
- grid.5611.30000 0004 1763 1124Department of Neurosciences, Biomedicine and Movement Sciences, University of Verona, 37131 Verona, Italy
| | - Bernardo Villa-Sánchez
- grid.5611.30000 0004 1763 1124Department of Neurosciences, Biomedicine and Movement Sciences, University of Verona, 37131 Verona, Italy ,grid.11696.390000 0004 1937 0351Center for Mind/Brain Sciences (CIMeC), University of Trento, 38068 Rovereto, Italy
| | - Filippo Rossignati
- grid.5611.30000 0004 1763 1124Department of Neurosciences, Biomedicine and Movement Sciences, University of Verona, 37131 Verona, Italy
| | - Mehran Emadi Andani
- grid.5611.30000 0004 1763 1124Department of Neurosciences, Biomedicine and Movement Sciences, University of Verona, 37131 Verona, Italy
| |
Collapse
|
4
|
Zhou J, Zhong S, Wu W. Hierarchical Motion Learning for Goal-Oriented Movements With Speed-Accuracy Tradeoff of a Musculoskeletal System. IEEE TRANSACTIONS ON CYBERNETICS 2022; 52:11453-11466. [PMID: 34520384 DOI: 10.1109/tcyb.2021.3109021] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Generating various goal-oriented movements via the flexible muscle model of the musculoskeletal system as fast and accurately as possible is a pressing problem, which is also the basis of most human adaptive behaviors, such as reaching, catching, interception, and pointing. This article focuses on the adaptive motion generation of fast goal-oriented motion on the musculoskeletal system by implementing the speed-accuracy tradeoff (SAT) in a hierarchical motion learning framework. First, we introduce Fitts' Law into the modified basal ganglia circuit-inspired iterative decision-making model for achieving dynamic and adaptive decision making. Then, as a time constraint, the decision is decomposed into a series of supervised terms by the proposed striatal FSI-SPN interneuron circuit-inspired velocity modulator to implement the tradeoff smoothly on the musculoskeletal system. Finally, an improved policy gradient algorithm is suggested to generate the muscle excitations of the modulated motion via the proposed muscle co-contraction policy, which promotes general cooperation between flexor and extensor muscles. In experiments, a redundant musculoskeletal arm model is trained to perform the adaptive quick pointing movements. By combining the muscle co-contraction policy with SAT, our algorithm shows the most efficient training and the best performance in the adaptive motion generation among the other three popular reinforcement learning algorithms on the musculoskeletal model.
Collapse
|
5
|
Fischer F, Bachinski M, Klar M, Fleig A, Müller J. Reinforcement learning control of a biomechanical model of the upper extremity. Sci Rep 2021; 11:14445. [PMID: 34262081 PMCID: PMC8280157 DOI: 10.1038/s41598-021-93760-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2020] [Accepted: 06/29/2021] [Indexed: 11/09/2022] Open
Abstract
Among the infinite number of possible movements that can be produced, humans are commonly assumed to choose those that optimize criteria such as minimizing movement time, subject to certain movement constraints like signal-dependent and constant motor noise. While so far these assumptions have only been evaluated for simplified point-mass or planar models, we address the question of whether they can predict reaching movements in a full skeletal model of the human upper extremity. We learn a control policy using a motor babbling approach as implemented in reinforcement learning, using aimed movements of the tip of the right index finger towards randomly placed 3D targets of varying size. We use a state-of-the-art biomechanical model, which includes seven actuated degrees of freedom. To deal with the curse of dimensionality, we use a simplified second-order muscle model, acting at each degree of freedom instead of individual muscles. The results confirm that the assumptions of signal-dependent and constant motor noise, together with the objective of movement time minimization, are sufficient for a state-of-the-art skeletal model of the human upper extremity to reproduce complex phenomena of human movement, in particular Fitts' Law and the [Formula: see text] Power Law. This result supports the notion that control of the complex human biomechanical system can plausibly be determined by a set of simple assumptions and can easily be learned.
Collapse
|
6
|
Takeda M, Nambu I, Wada Y. Forward Inverse Relaxation Model Incorporating Movement Duration Optimization. Brain Sci 2021; 11:brainsci11020149. [PMID: 33498720 PMCID: PMC7912108 DOI: 10.3390/brainsci11020149] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2020] [Revised: 12/23/2020] [Accepted: 01/20/2021] [Indexed: 11/16/2022] Open
Abstract
A computational trajectory formation model based on the optimization principle, which introduces the forward inverse relaxation model (FIRM) as the hardware and algorithm, represents the features of human arm movements well. However, in this model, the movement duration was defined as a given value and not as a planned value. According to considerable empirical facts, movement duration changes depending on task factors, such as required accuracy and movement distance thus, it is considered that there are some criteria that optimize the cost function. Therefore, we propose a FIRM that incorporates a movement duration optimization module. The movement duration optimization module minimizes the weighted sum of the commanded torque change term as the trajectory cost, and the tolerance term as the cost of time. We conducted a behavioral experiment to examine how well the movement duration obtained by the model reproduces the true movement. The results suggested that the model movement duration was close to the true movement. In addition, the trajectory generated by inputting the obtained movement duration to the FIRM reproduced the features of the actual trajectory well. These findings verify the use of this computational model in measuring human arm movements.
Collapse
|