Initial Learning of Timing in Combined Serial Movements and a No-Movement Situation

2005 ◽  
Vol 22 (3) ◽  
pp. 509-530 ◽  
Author(s):  
Jacques LaRue
Keyword(s):  
Young Adults ◽  
Movement Time ◽  
Movement Speed ◽  
Timing Error ◽  
Timing Errors ◽  
Initial Learning ◽  
Movement Sequence ◽  
Movement Segment ◽  
Continuous Movements ◽  
Timing Processes

We investigate differences in timing errors in a task that imitated the movement sequence of a cello player. We trained a group of 17 young adults to perform a sequence of linear reversal movements of different lengths but with a constant movement time. Thus, each segment required the movement speed to be changed. The sequence had to be performed with fluidity, except for a �no-movement� segment that was embedded in the movement series. Feedback on timing was given for each segment. Results from this experiment show that the no-movement segment is more variable than any of the movement segments. There was no significant correlation between the timing errors of the successive movements and the timing error of the pause. These results provide further evidence in favor of two distinct timing processes: one used for continuous movements and one used for no-movement and discontinuous movements.

Control of sequential movements: evidence for generalized motor programs

1984 ◽  
Vol 52 (5) ◽  
pp. 787-796 ◽  
Author(s):  
M. C. Carter ◽  
D. C. Shapiro
Keyword(s):  
Temporal Pattern ◽  
Peak Velocity ◽  
Movement Time ◽  
Movement Speed ◽  
Relative Timing ◽  
Motor Programs ◽  
Pronator Teres ◽  
Movement Sequence ◽  
Total Movement ◽  
Total Movement Time

The neuromotor processes underlying the control of rapid sequential limb movements were investigated. Subjects learned to pronate and supinate their forearms rapidly to four target locations in a specific spatio-temporal pattern under two movement-time conditions. The response sequence was first performed in a total movement time of 600 ms. Subjects were then told to produce the movement as quickly as possible while ignoring any timing pattern that they had previously learned. Electromyographic (EMG) signals were recorded from the biceps brachii and pronator teres muscles. Kinematic and EMG analyses were performed to investigate the temporal characteristics underlying the two movement-time conditions. When subjects produced the response as quickly as possible, average movement time to perform each reversal movement decreased while average peak velocity increased. Average total movement time was reduced by approximately 100 ms. Although movement time decreased, the proportion of total time to perform each movement of the sequence remained essentially invariant between movement-time conditions. Similar results were obtained for velocity. The time at which peak velocity was achieved occurred earlier in absolute time, although when normalized to the proportion of total movement time, the time to reach peak velocity was also invariant. Thus subjects proportionally compressed the entire movement sequence in time. The EMG analysis demonstrated that total EMG time decreased 89 ms on the average when subjects sped up the movement sequence. Thus average burst durations for both the biceps and pronator teres muscles decreased when movement speed increased. When burst durations were normalized to a proportion of total EMG time, the average proportion of time each muscle was active remained invariant. Therefore, the temporal pattern of activity for the biceps and pronator teres muscles were also proportionally compressed. The present experiment provided additional evidence for the structure of generalized motor programs consisting of invariant and variant features. Movement speed was considered a variant feature, which is specified each time the program is executed. Relative timing, the proportion of total time to produce each segment of the response, was considered to be an invariant feature and inherent in the structure of the motor program. Support for the invariance of relative timing was observed at both the kinematic and neuromuscular levels of analyses. Alternative models (9-11, 24) were found inadequate to account for the invariance of relative timing with the variation in movement time observed in the present experiment.

Age Differences in Movement Time over Distances Proportional to Size

1979 ◽  
Vol 48 (1) ◽  
pp. 309-310 ◽  
Author(s):  
Kathleen M. Haywood
Keyword(s):  
Young Adults ◽  
Age Differences ◽  
Movement Time ◽  
Early Adulthood ◽  
Arm Movement ◽  
Limb Length ◽  
Movement Speed

Investigations of the differences in movement speed over the age span, childhood to early adulthood, have typically confounded age with size differences which bring about mechanical differences in the task. The present study investigated the effect on arm movement time of confounding age and limb length. Young adults and childen 7 to 9 yr. of age were tested over a distance proportional to their arm length. Despite moving over a proportionally shorter distance, the children were significantly slower than the adults, suggesting that age differences in performance are not solely attributable to size differences among subjects.

scholarly journals Targeting in Virtual Workspaces: motor learning consolidates spatial memory for performance clusters

2019 ◽  
Author(s):  
Bradly Alicea ◽  
Corey Bohil ◽  
Frank Biocca ◽  
Charles Owen
Keyword(s):  
Repeated Measures ◽  
Target Location ◽  
Movement Time ◽  
Three Dimensional ◽  
Arm Movement ◽  
Hierarchical Cluster ◽  
Movement Speed ◽  
Advantages And Disadvantages ◽  
Training Interval ◽  
Speed And Accuracy

Our objective was to focus on linkages between the process of learning and memory and the placement of objects within an array of targets in a virtual workspace. Participants were instructed to place virtual objects serially within a three-dimensional target array. One phase presented each target sequentially, and required participants to make timed ballistic arm movements. The other phase presented all nine targets simultaneously, which required ballistic arm movement towards the correct target location as recalled from the learning phase. Movement time and accuracy were assessed using repeated-measures ANOVA, a hierarchical cluster analysis, and a multiple linear regression. Collectively, this revealed numerous speed and accuracy advantages and disadvantages for various positional combinations. Upper positions universally yielded longer movement times and larger error measurements. Individual ability for mental rotation combined with task learning over a fixed training interval was found to predict accuracy for specific locations. The prediction that location influences movement speed and accuracy was supported, but with some caveats. These results may be particularly useful in the design of instructor stations and other hybrid physical-virtual workspaces.

Movement Sequence-Related Activity Reflecting Numerical Order of Components in Supplementary and Presupplementary Motor Areas

1998 ◽  
Vol 80 (3) ◽  
pp. 1562-1566 ◽  
Author(s):  
William T. Clower ◽  
Garrett E. Alexander
Keyword(s):  
Movement Time ◽  
Electromyographic Activity ◽  
Related Activity ◽  
Spatial Variables ◽  
Movement Sequence ◽  
Sequence Components ◽  
Numerical Order ◽  
Relational Order ◽  
Sequencing Task ◽  
Motor Areas

Clower, William T. and Garrett E. Alexander. Movement sequence-related activity reflecting numerical order of components in supplementary and presupplementary motor areas. J. Neurophysiol. 80: 1562–1566, 1998. The supplementary motor area (SMA) and presupplementary motor areas (pre-SMA) have been implicated in movement sequencing, and neurons in SMA have been shown to encode what might be termed the relational order among sequence components (e.g., movement X followed by movement Y). To determine whether other aspects of movement sequencing might also be encoded by SMA or pre-SMA neurons, we analyzed task-related activity recorded from both areas in conjunction with a sequencing task that dissociated the numerical order of components (e.g., movement X as the 2nd component, irrespective of which movements precede or follow X). Sequences were constructed from eight component movements, each characterized by three spatial variables (origin, direction, and endpoint). Task-related activity recorded from 56 SMA and 63 pre-SMA neurons was categorized according to both the epoch (delay, reaction time, and movement time) and the spatial variable or component movement with which it was associated. All but one instance of task-related activity was selective for one of the spatial variables (SV-selective) rather than for any of the component movements themselves. Of 110 instances of SV-selective activity in SMA, 43 (39%) showed significant effects of numerical order. The corresponding incidence in pre-SMA, 82 (71%) of 116, was substantially higher ( P < 0.00001). No effects of numerical order were evident among the hand paths, movement times, or electromyographic activity associated with task performance. We concluded that neurons in SMA and pre-SMA may encode the numerical order of components, at least for sequences that are distinguished mainly by that aspect of component ordering.

Cognitive-Motor Abilities of the Elderly Driver

1992 ◽  
Vol 34 (1) ◽  
pp. 53-65 ◽  
Author(s):  
George E. Stelmach ◽  
Ariella Nahom
Keyword(s):  
Response Selection ◽  
Focal Point ◽  
Movement Time ◽  
Force Production ◽  
The Elderly ◽  
Movement Speed ◽  
Age Difference ◽  
Response Preparation ◽  
Movement Initiation ◽  
Elderly Driver

This article reviews literature that documents the effects of age on motor performance as it relates to driving behavior. Movement initiation is the focal point of the first part of the article, and it is considered in terms of absolute age differences when functional manipulations are made, such as response preparation, response selection, response programming, and complexity. The second part of the article addresses age difference in the context of movement execution characteristics; differences in movement speed, force production, limb coordination, and sensory motor integration are considered. Movement time and movement kinematics and kinetics are the principal dependent measures reviewed. Adults were found to initiate and execute movements more slowly and with less precision as they age, which may contribute to the decline of their driving skill. Most of the data reviewed were obtained in laboratory settings; nevertheless, they suggest how age may impair the elderly driver.

scholarly journals A Modified Kwee–Van Woerden Method for Eclipse Minimum Timing with Reliable Error Estimates

Galaxies ◽  
2020 ◽  
Vol 9 (1) ◽  
pp. 1
Author(s):  
Hans J. Deeg
Keyword(s):  
Error Estimates ◽  
Measurement Errors ◽  
Fundamental Problem ◽  
Space Mission ◽  
Original Method ◽  
External Input ◽  
Improved Method ◽  
Timing Error ◽  
Timing Errors

The Kwee–van Woerden (KvW) method used for the determination of eclipse minimum times has been a staple in eclipsing binary research for decades, due its simplicity and the independence of external input parameters, which also makes it well-suited to obtaining timings of exoplanet transits. However, its estimates of the timing error have been known to have a low reliability. During the analysis of very precise photometry of CM Draconis eclipses from TESS space mission data, KvW’s original equation for the timing error estimate produced numerical errors, which evidenced a fundamental problem in this equation. This contribution introduces an improved approach for calculating the timing error with the KvW method. A code that implements this improved method, together with several further updates of the original method, are presented. An example of the application to CM Draconis light curves from TESS is given. The eclipse minimum times are derived with the KvW method’s three original light curve folds, but also with five and seven folds. The use of five or more folds produces minimum timings with a substantially better precision. The improved method of error calculation delivers consistent timing errors which are in excellent agreement with error estimates obtained by other means. In the case of TESS data from CM Draconis, minimum times with an average precision of 1.1 s are obtained. Reliable timing errors are also a valuable indicator for evaluating if a given scatter in an O-C diagram is caused by measurement errors or by a physical period variation.

scholarly journals Premature oral pre-shaping for feeding in elderly population with risk of aspiration pneumonia

PLoS ONE ◽  
2021 ◽  
Vol 16 (2) ◽  
pp. e0246804
Author(s):  
Yoshiki Tamaru ◽  
Akiyoshi Matsugi ◽  
Shinzo Masaki ◽  
Yoshihito Tsubouchi ◽  
Akiyoshi Yanagawa
Keyword(s):  
Young Adults ◽  
High Risk ◽  
Elderly People ◽  
Aspiration Pneumonia ◽  
Elderly Population ◽  
Movement Time ◽  
The Other ◽  
Feeding Time ◽  
Healthy Elderly ◽  
Risk Of Aspiration

The aim of this study was to determine the abnormal hand and mouth behavior before actual swallowing for eating in elderly people with high risk of aspiration pneumonia. Ten elderly people with a diagnosis of aspiration pneumonia (EAP), 15 healthy elderly (HE) people, and 21 young adults (YA) were enrolled. The feeding time and the timing of the maximum distance between the upper and lower lips were extracted using a motion analyzer during self-feeding and assisted-feeding. The results showed that feeding time in EAP was significantly longer than that for the other groups in self- and assisted-feeding. In self-feeding, the timing of mouth-preparation in the EAP group was significantly earlier than that in the other groups; conversely, in assisted-feeding, the timing in EAP was significantly delayed. Our results indicate that abnormal preparation of mouth-shape and movement time of hand before actual swallowing in both self- and assisted-feeding may exist in elderly people with previous experience of aspiration pneumonia.

Comparison of Manipulative Indicators of Students and Therapists Using a Robotic Arm: A Feasibility Study

2021 ◽  
Vol 11 (20) ◽  
pp. 9403
Author(s):  
Koike Yuji ◽  
Okino Akihisa ◽  
Takeda Kazuhisa ◽  
Takanami Yasuhiro ◽  
Toyohiro Hamaguchi
Keyword(s):  
Elbow Joint ◽  
Muscle Tone ◽  
Peak Velocity ◽  
Movement Time ◽  
Analysis Of Covariance ◽  
Movement Speed ◽  
Joint Movement ◽  
Exercise Time ◽  
Kinematic Data ◽  
Extended Position

In this study, the motion therapy elements necessary for student education were clarified through comparison of the therapeutic motion techniques of therapists and students using an educational arm robot (Samothrace: SAMO). Eight therapists and 25 fourth-year students participated. The therapeutic motion therapy task was a reciprocating exercise in which the elbow joint of SAMO was flexed from an extended position and then re-extended. This was performed for three types of muscle tone intensities (mild, moderate, and severe), and the peak velocity, angle ratio, velocity time, and movement time were recorded using SAMO. These data were then compared using analysis of covariance. It was found that the SAMO elbow joint kinematic data generated by therapists differed significantly from those of students for different muscle tones. Multiple comparisons showed that the therapeutic motion techniques of students were associated with a higher peak velocity, smaller peak angle ratio, and shorter peak velocity time and movement time than those of the therapists. Thus, when students learn therapeutic motion techniques, they should be taught to (1) deal with multiple muscle tone intensities and (2) reduce the joint movement speed applied to the patient to extend the exercise time and ensure maximum joint movement range.

Two components of muscle activation: scaling with the speed of arm movement

1992 ◽  
Vol 67 (4) ◽  
pp. 931-943 ◽  
Author(s):  
M. Flanders ◽  
U. Herrmann
Keyword(s):  
Muscle Activation ◽  
Movement Time ◽  
Vertical Plane ◽  
Arm Movement ◽  
Movement Speed ◽  
Weighting Coefficient ◽  
Emg Activity ◽  
Tonic Component ◽  
Force Element ◽  
Weighting Coefficients

1. The temporal waveform of muscle activity was related to the speed of arm movement. Speed was expressed in terms of the duration of a fixed amplitude movement or the "movement time." 2. Human subjects moved their arms to targets in three-dimensional space. The right arm started at a standard initial position and moved directly to the target in a single stroke. The targets were placed in various directions in a vertical plane. The arm movements consisted of shoulder and elbow rotations. 3. Subjects were required to vary the speed of their movements. In most of the experiments, trials with different movement times were randomly ordered. One of the experiments also included randomly interspersed static trials, in which the subject held the arm still at the initial posture, the final posture, or halfway between the two extremes. 4. Electromyographic (EMG) activity was recorded from several superficial elbow and/or shoulder muscles. The time base of rectified EMG records was normalized for movement time such that records from movements with various speeds were compressed to align the ending times of the movements. 5. A principal component (PC) analysis revealed that the compressed EMG waveforms could be described by a summation of PC1 and PC2 waveforms; each individual EMG waveform was approximated by a weighted sum of these two components. 6. The PC1 weighting coefficients scaled down in a monotonic relationship with movement time such that the fastest movement corresponded to a large positive weighting coefficient and the slowest movement corresponded to a small positive weighting coefficient. The PC2 weighting coefficients exhibited a similar monotonic scaling, but the values ranged from positive to negative. Further analysis demonstrated that these two components can be mathematically transformed into a tonic waveform with a constant mathematically transformed into a tonic waveform with a constant weighting coefficient and a phasic waveform with positive weighting coefficients that scale down with movement time. 7. The amplitude scaling of EMG records cannot be described by a single component, but instead requires a summation of two separate components. The tonic component may correspond to the force element needed to counteract gravity, because the magnitude of this element does not scale with movement speed. The phasic component may correspond to the force element that scales quadratically to produce a linear increase in velocity.

Organizing principles for single-joint movements. II. A speed-sensitive strategy

1989 ◽  
Vol 62 (2) ◽  
pp. 358-368 ◽  
Author(s):  
D. M. Corcos ◽  
G. L. Gottlieb ◽  
G. C. Agarwal
Keyword(s):  
Muscle Activation ◽  
Human Subjects ◽  
Movement Time ◽  
Initial Position ◽  
Joint Torque ◽  
Movement Speed ◽  
Movement Kinematics ◽  
Antagonist Muscles ◽  
Speed Accuracy ◽  
Organizing Principles

1. Normal human subjects made discrete flexions of the elbow over a fixed distance in the horizontal plane from a stationary initial position to a visually defined target. We measured joint angle, acceleration, and electromyograms (EMGs) from two agonist and two antagonist muscles. 2. Changes in movement speed were elicited either by explicit instruction to the subject or by adjusting the target width. Instructions always required accurately stopping in the target zone. 3. Peak inertial torques and accelerations, movement times, and integrated EMGs were all highly correlated with speed. We show that inertial torque can be used as a linking variable that is almost sufficient to explain all correlations between the task, the EMG, and movement kinematics. 4. When subjects perform tasks that require control of movement speed, they adjust the rate at which torque is developed by the muscles. This rate is modulated by the way in which the muscles are activated. The rate at which joint torque develops is correlated with the rate at which the agonist EMG rises as well as with integrated EMG. 5. The antagonist EMG shows two components. The latency of the first is 30-50 ms and independent of movement dynamics. The latency of the second component is proportional to movement time. The rate of rise and area of both components scale with torque. 6. We propose organizing principles for the control of single-joint movements in which tasks are performed by one of two strategies. These are called speed-insensitive and speed-sensitive strategies. 7. A model is proposed in which movements made under a speed-sensitive strategy are executed by controlling the intensity of an excitation pulse delivered to the motoneuron pool. The effect is to regulate the rate at which joint torque, and consequently acceleration, increases. 8. Movements of variable distance, speed, accuracy, and load are shown to be controlled by one of two consistent sets of rules for muscle activation. These rules apply to the control of both the agonist and antagonist muscles. Rules of activation lead to distinguishable patterns of EMG and torque development. All observable changes in movement kinematics are explained as deterministic consequences of these effects.

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