scholarly journals Influence of switching rule on motor learning

2018 ◽  
Author(s):  
Ken Takiyama ◽  
Koutaro Ishii ◽  
Takuji Hayshi
Keyword(s):  
Motor Learning ◽  
Sensory Stimulus ◽  
Reaching Movements ◽  
Movement Direction ◽  
Learning Effects ◽  
Visuomotor Rotation ◽  
Switching Rule ◽  
Arm Reaching ◽  
Partial Transfer ◽  
The Difference

AbstractHumans and animals can flexibly switch rules to generate appropriate motor commands; for example, actions can be flexibly produced toward a sensory stimulus (e.g., pro-saccade or pro-reaching) or away from a sensory stimulus (e.g., anti-saccade or anti-reaching). Distinct neural activities are related to pro- and anti-movement actions; however, the effects of switching rules on motor learning are unclear. Here, we study the effect of switching rules on motor learning using pro- and anti-arm-reaching movements and a visuomotor rotation task. Although previous results support the perfect availability of learning effects under the same required movements, we show that the learning effects trained in pro-reaching movements are partially rather than perfectly available in anti-reaching movements even under the same required movement direction between those two conditions. The partial transfer is independent of the difference in the visual cue, the cognitive demand, and the actual movement direction between the pro- and anti-reaching movements. We further demonstrate that the availability of learning effects trained with pro-reaching movements is partial not only in anti-reaching movements but in reaching movements with other rules and the availability of learning effects trained with anti-reaching movements is also partial in pro-reaching movements. We thus conclude that the switching rule causes the availability of learning effects to be partial rather than perfect even under same planned movements.New & NoteworthyMost motor learning experiments supported the involvement of planned movement directions in motor learning; the learning effects trained in a movement direction can be available at movement directions close to the trained one. Here, we show that the availability of motor learning effects is partial rather than perfect even under the same planned movements when rule is switched, which indicates that sports training and rehabilitation should include various situations under the same required motions.

scholarly journals Visuomotor learning is dependent on direction-specific error saliency

2018 ◽  
Vol 120 (1) ◽  
pp. 162-170 ◽  
Author(s):  
Wanying Jiang ◽  
Xianzhi Yuan ◽  
Cong Yin ◽  
Kunlin Wei
Keyword(s):  
Motor Learning ◽  
Athletic Training ◽  
Oblique Effect ◽  
Movement Direction ◽  
Visuomotor Rotation ◽  
Directional Effect ◽  
Initial Learning ◽  
Long Time ◽  
Cardinal Directions ◽  
Saving Effect

People perceive better in cardinal directions compared with oblique ones. This directional effect, called oblique effect, has been documented in perception studies for a long time. However, typical motor studies do not differentiate learning in different directions. In this study we identify a significant directional effect in motor learning using visuomotor rotation paradigms. We find that adaptation to visual perturbations yields more savings when both initial learning and relearning are performed in cardinal directions than in oblique directions. We hypothesize that this directional effect arises from relatively higher error saliency in cardinal directions. Consistent with this hypothesis, we successfully increased savings in the oblique directions, which showed no saving effect before, by enhancing the error saliency with augmented visual feedback during learning. Our findings suggest that movement direction plays an important role in motor learning, especially when learning signals are direction specific. Our results also provide new insights about the role of motor errors in the formation and retrieval of motor memory and practical implications for promoting learning in motor rehabilitation and athletic training. NEW & NOTEWORTHY People perceive better when the stimulus is in cardinal directions than in oblique directions. Whether a similar directional effect exists in motor learning is unknown. Using a motor learning paradigm, we show that people relearn to compensate for a previously encountered perturbation faster when they move in cardinal directions than when they move in oblique directions. Further experimentation supports that this motor directional effect likely results from better sensory saliency of motor errors in cardinal directions.

scholarly journals Target size matters: target errors contribute to the generalization of implicit visuomotor learning

2016 ◽  
Vol 116 (2) ◽  
pp. 411-424 ◽  
Author(s):  
Maayan Reichenthal ◽  
Guy Avraham ◽  
Amir Karniel ◽  
Lior Shmuelof
Keyword(s):  
Open Loop ◽  
Reaching Movements ◽  
Prediction Errors ◽  
Learning Mechanisms ◽  
Implicit Processes ◽  
Small Ball ◽  
Target Error ◽  
Arm Reaching ◽  
Before And After ◽  
The Difference

The process of sensorimotor adaptation is considered to be driven by errors. While sensory prediction errors, defined as the difference between the planned and the actual movement of the cursor, drive implicit learning processes, target errors (e.g., the distance of the cursor from the target) are thought to drive explicit learning mechanisms. This distinction was mainly studied in the context of arm reaching tasks where the position and the size of the target were constant. We hypothesize that in a dynamic reaching environment, where subjects have to hit moving targets and the targets' dynamic characteristics affect task success, implicit processes will benefit from target errors as well. We examine the effect of target errors on learning of an unnoticed perturbation during unconstrained reaching movements. Subjects played a Pong game, in which they had to hit a moving ball by moving a paddle controlled by their hand. During the game, the movement of the paddle was gradually rotated with respect to the hand, reaching a final rotation of 25°. Subjects were assigned to one of two groups: The high-target error group played the Pong with a small ball, and the low-target error group played with a big ball. Before and after the Pong game, subjects performed open-loop reaching movements toward static targets with no visual feedback. While both groups adapted to the rotation, the postrotation reaching movements were directionally biased only in the small-ball group. This result provides evidence that implicit adaptation is sensitive to target errors.

scholarly journals Effect of Trial Order and Error Magnitude on Motor Learning by Observing

2010 ◽  
Vol 104 (3) ◽  
pp. 1409-1416 ◽  
Author(s):  
Liana E. Brown ◽  
Elizabeth T. Wilson ◽  
Sukhvinder S. Obhi ◽  
Paul L. Gribble
Keyword(s):  
Motor Learning ◽  
Force Field ◽  
Reaching Movements ◽  
Error Magnitude ◽  
Orderly Fashion ◽  
Nature Of Information ◽  
The Difference ◽  
Movement Curvature

Watching an actor make reaching movements in a perturbing force field provides the observer with information about how to compensate for that force field. Here we asked two questions about the nature of information provided to the observer. Is it important that the observer learn the difference between errant (curved) movements and goal (straight) movements by watching the actor progress in a relatively orderly fashion from highly curved to straight movements over a series of trials? Or is it sufficient that the observer sees only reaching errors in the force field (FF)? In the first experiment, we found that observers performed better if they observed reaches in a FF that was congruent, rather than incongruent, with the FF used in a later test. Observation-trial order had no effect on performance, suggesting that observers understood the goal in advance and perhaps learned about the force-field by observing movement curvature. Next we asked whether observers learn optimally by observing the actor's mistakes (high-error trials), if they learn by watching the actor perform with expertise in the FF (low-error trials), or if they need to see contrast between errant and goal behavior (a mixture of both high- and low-error trials). We found that observers who watched high-error trials were most affected by observation but that significant learning also occurred if observers watched only some high-error trials. This result suggests that observers learn to adapt their reaching to an unpredictable FF best when they see the actor making mistakes.

scholarly journals Performing a reaching task with one arm while adapting to a visuomotor rotation with the other can lead to complete transfer of motor learning across the arms

2015 ◽  
Vol 113 (7) ◽  
pp. 2302-2308 ◽  
Author(s):  
Jinsung Wang ◽  
Yuming Lei ◽  
Jeffrey R. Binder
Keyword(s):  
Motor Learning ◽  
Visuomotor Adaptation ◽  
The Other ◽  
Movement Direction ◽  
Error Feedback ◽  
Initial Training ◽  
Visuomotor Rotation ◽  
Reaching Task ◽  
Model Free ◽  
And Task

The extent to which motor learning is generalized across the limbs is typically very limited. Here, we investigated how two motor learning hypotheses could be used to enhance the extent of interlimb transfer. According to one hypothesis, we predicted that reinforcement of successful actions by providing binary error feedback regarding task success or failure, in addition to terminal error feedback, during initial training would increase the extent of interlimb transfer following visuomotor adaptation ( experiment 1). According to the other hypothesis, we predicted that performing a reaching task repeatedly with one arm without providing performance feedback (which prevented learning the task with this arm), while concurrently adapting to a visuomotor rotation with the other arm, would increase the extent of transfer ( experiment 2). Results indicate that providing binary error feedback, compared with continuous visual feedback that provided movement direction and amplitude information, had no influence on the extent of transfer. In contrast, repeatedly performing (but not learning) a specific task with one arm while visuomotor adaptation occurred with the other arm led to nearly complete transfer. This suggests that the absence of motor instances associated with specific effectors and task conditions is the major reason for limited interlimb transfer and that reinforcement of successful actions during initial training is not beneficial for interlimb transfer. These findings indicate crucial contributions of effector- and task-specific motor instances, which are thought to underlie (a type of) model-free learning, to optimal motor learning and interlimb transfer.

Cerebellar neuronal activity related to whole-arm reaching movements in the monkey

1989 ◽  
Vol 62 (1) ◽  
pp. 198-211 ◽  
Author(s):  
P. A. Fortier ◽  
J. F. Kalaska ◽  
A. M. Smith
Keyword(s):  
Reaction Time ◽  
Reaching Movements ◽  
Movement Direction ◽  
Sample Population ◽  
Response Patterns ◽  
Cortical Cells ◽  
Cerebellar Neurons ◽  
Starting Position ◽  
Preferred Direction ◽  
Arm Reaching

1. Three monkeys were trained to make whole-arm reaching movements from a common central starting position toward eight radially arranged targets disposed at 45 degrees intervals. A sample of 312 cerebellar neurons with proximal-arm receptive fields or discharge related to shoulder or elbow movements was studied in the task. The sample included 69 Purkinje cells, 115 unidentified cortical cells, 65 interpositus neurons, and 63 dentate units. 2. The reaching task was divided into three movement-related epochs: a reaction time, a movement time, and holding over the target. All neurons demonstrated significant changes in discharge during one or more of these three epochs. Almost all of the cells (95%) showed a significant change in activity during the movement, whereas 68-69% of the cells showed significant changes from premovement activity during the reaction time and holding periods. 3. During the combined reaction time-movement period, 231/312 cells were strongly active in the task. Of these, 151 cells (65.4%) demonstrated unimodal directional responses. Sixty-three had a reciprocal relation to movement direction, whereas 88 showed only graded increases or decreases in activity. A further 37 cells (16.0%) were nondirectional, with statistically uniform changes in discharge in all eight directions. The remaining 43 cells (18.6%) showed significant differences in activity for different directions of movement, but their response patterns were not readily classifiable. 4. The proportion of directional versus nondirectional cells was consistent across the four cell populations. However, graded response patterns were more common and reciprocal responses less common among Purkinje and dentate neurons than among unidentified cortical cells and interpositus neurons. 5. The distribution of preferred directions of the population of cerebellar neurons covered all possible movement directions away from the common central starting position in the horizontal plane. When the preferred direction of each cell in the sample population was aligned, the mean direction-related activity of the cerebellar population formed a bell-shaped tuning curve for the activity recorded during both the reaction time and the movement, as well as during the time the arm maintained a fixed posture over the targets. A vector representation also showed that the overall activity of the cerebellar population during normal reaching arm movements generated a signal that varied with movement direction. 6. These results demonstrate that the cerebellum generates a signal that varies with the direction of movement of the proximal arm during normal aimed reaching movements and is consistent with a role in the control of the activity of muscles or muscle groups generating these movements.

Accuracy of Children on an Open-Loop Pointing Task

1978 ◽  
Vol 47 (3_suppl) ◽  
pp. 1079-1082 ◽  
Author(s):  
L. Hay
Keyword(s):  
Open Loop ◽  
Reaching Movements ◽  
Manual Pointing ◽  
Pointing Task ◽  
The Difference ◽  
Passive Movements

The accuracy of active and passive movements was measured in 4-yr.- to 11-yr.-old children and in adults performing a visuo-manual pointing task without seeing their limbs. Accuracy varied according to age and nature of movement. The younger children performed accurate movements. At age 7 the accuracy suddenly decreased while the difference between active and passive movements increased. Between 7 and 11 yr., the active performance improved progressively until attaining an adult-like level, while the passive performance remained unchanged. It is concluded that a change occurs in the manner of controlling reaching movements at age 7.

Changes in motor cortex activity during reaching movements with similar hand paths but different arm postures

1995 ◽  
Vol 73 (6) ◽  
pp. 2563-2567 ◽  
Author(s):  
S. H. Scott ◽  
J. F. Kalaska
Keyword(s):  
Motor Cortex ◽  
Sagittal Plane ◽  
Single Cells ◽  
Reaching Movements ◽  
Movement Direction ◽  
Tonic Activity ◽  
Population Vector ◽  
Significant Difference ◽  
Direction Of Movement ◽  
Kinematics And Kinetics

1. Neuronal activity was recorded in the motor cortex of a monkey that performed reaching movements with the use of two different arm postures. In the first posture (control), the monkey used its natural arm orientation, approximately in the sagittal plane. In the second posture (abducted), the monkey had to adduct its elbow nearly to shoulder level to grasp the handle. The path of the hand between targets was similar in both arm postures, but the joint kinematics and kinetics were different. 2. In both postures, the activity of single cells was often broadly tuned with movement direction and static arm posture over the targets. In a large proportion of cells, either the level of tonic activity, the directional tuning, or both, varied between the two postures during the movement and target hold periods. 3. For most directions of movement, there was a statistically significant difference in the direction of the population vector for the two arm postures. Furthermore, whereas the population vector tended to point in the direction of movement for the control posture, there was a poorer correspondence between the direction of movement and the population vector for the abducted posture. These observed changes are inconsistent with the notion that the motor cortex encodes purely hand trajectory in space.

Sensorimotor knowledge from task-irrelevant feedback contributes to motor learning

2021 ◽  
Author(s):  
Wanying Jiang ◽  
Yajie Liu ◽  
Yuqing Bi ◽  
Kunlin Wei
Keyword(s):  
Motor Learning ◽  
Perceptual Learning ◽  
Implicit Learning ◽  
Motor Adaptation ◽  
Strategic Learning ◽  
Visuomotor Rotation ◽  
Saving Effect ◽  
Sensorimotor Knowledge ◽  
Sensory Processes ◽  
Task Irrelevant

Exposure to task-irrelevant feedback leads to perceptual learning, but its effect on motor learning has been understudied. Here we asked human participants to reach a visual target with a hand-controlled cursor while observing another cursor moving independently in a different direction. While the task-irrelevant feedback did not change the main task's performance, it elicited robust savings in subsequent adaptation to classical visuomotor rotation perturbation. We demonstrated that the saving effect resulted from a faster formation of strategic learning through a series of experiments, not from gains in the implicit learning process. Furthermore, the saving effect was robust against drastic changes in stimulus features (i.e., rotation size or direction) or task types (i.e., for motor adaptation and skill learning). However, the effect was absent when the task-irrelevant feedback did not carry the visuomotor relationship embedded in visuomotor rotation. Thus, though previous research on perceptual learning has related task-irrelevant feedback to changes in early sensory processes, our findings support its role in acquiring abstract sensorimotor knowledge during motor learning. Motor learning studies have traditionally focused on task-relevant feedback, but our study extends the scope of feedback processes and sheds new light on the dichotomy of explicit and implicit learning in motor adaptation as well as motor structure learning.

Role of Non-Lesioned Hemisphere in Affected Arm Reaching Movements After Severe Stroke: A Pilot Study

2014 ◽  
Vol 95 (10) ◽  
pp. e26
Author(s):  
Sambit Mohapatra ◽  
Evan Chan ◽  
Rachael Harrington ◽  
Alexander Dromerick ◽  
Peter Turkeltaub ◽  
...  
Keyword(s):  
Pilot Study ◽  
Reaching Movements ◽  
Severe Stroke ◽  
Arm Reaching

Feedback Control of Functional Electrical Stimulation for 2-D Arm Reaching Movements

2018 ◽  
Vol 26 (10) ◽  
pp. 2033-2043 ◽  
Author(s):  
Reza Sharif Razavian ◽  
Borna Ghannadi ◽  
Naser Mehrabi ◽  
Mark Charlet ◽  
John McPhee
Keyword(s):  
Electrical Stimulation ◽  
Feedback Control ◽  
Functional Electrical Stimulation ◽  
Reaching Movements ◽  
Arm Reaching
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