lateralised motor control: hemispheric damage and the loss of deftness
Methods: This study investigated the inter-task differences in manual movement asymmetry (such as speed, accuracy, and independent finger movement) in patients with left unilateral lesions (LHD)
Or the right hemisphere (RHD)
And normal control (C).
Results: normal subjects showed maximum right-hand preference for a task requiring rapid coordination and precise independent finger movements (coin rotation).
Both hemisphere damaged groups showed lateral motion defects, but significant differences in the degree of asymmetry were found (RHD>C>LHD)
Subjects with LHD had side-to-side and side-to-side defects.
The biggest homelike defects in LHD subjects are those tasks that require precision (
Nail plate with slot and coin rotation).
Conclusion: the degree of Hemisphere specialization partly depends on the nature of the exercise task, and for tasks requiring precise and coordinated movement of independent fingers, movement control of the left hemisphere is necessary.
Methods the sample of subjects consisted of 86 right handed, determined by profit hand inventory, and 10 recruited and tested at the New Orleans Veterans Administration Medical Center.
Subjects included 60 normal controls (C)
13 cases of unilateral lesions were confined to the left hemisphere (LHD)
13 cases of unilateral lesions in the right hemisphere (RHD; see appendix A).
The age of the subjects ranged from 40 to 79 (Meancontrols = month number. 9, meanLHD=58. 5, meanRHD=63. 4).
Screening patients for a history of neurological and mental illness or a history of severe alcohol/drug abuse.
If the patient is not treated, they are also excluded from the study
Nervous system disease that may cause motor disability, or if they are unable to complete the exercise test with both hands.
It is unusual for the two patients to have exactly the same size, structure and location of the lesion.
In addition, there are individual differences in the size, location and configuration of gyri and sulci, even in morbid cases.
Therefore, there was no study that fully matched the left and right hemisphere lesions, in which subjects were entered in sequence and did not attempt to find subjects whose hemisphere lesions accurately mirror each other (or each other).
View this table: View the inline View pop-up table 1 representation (SD)
For motor tasksView, this table: View the average asymmetric quotient ((R−L)/R)
Through group View this table: View the clinical and lesion data of patients with inline View popupAppendix LHD and RHD, pair by testing grip strength with hand held parking force meter
The grip score is based on the average of the three trials per hand, expressed in the applied pressure kg.
We used several tests to evaluate dexterity, including: finger tapping test (
Measure the speed of open loop motion, 11 and nail plate test with grooves (
Evaluate closed loop accuracy.
The nail plate of the groove is composed of 5 × 5 key hole shape hole matrix in different directions.
The score of the groove DingTalk plate is the amount of time required to complete the task, including the additional time when the subject put down the DingTalk.
Because the nail plate of the groove mainly measures the accuracy of the near-side movement, we use the new \"Coin rotation\" Task 13 designed by Mendoza and colleagues to measure the accuracy of the far-side movement.
This test also requires the cooperation of independent finger movements.
In this coin rotation task, the subject rotated 180 degrees as quickly as possible between the thumb, index finger and middle finger, 20 times.
The examiner measures the time it takes to complete the task, including episodes where coins fall.
Unlike finger tap and groove nail board tests, clinicians can use coin spin tests at the bedside without having to buy or carry additional equipment.
Finally, we tested the subjects with handheld devices (Lion)tapping device.
Unlike previous tests, this test does not require independent finger movements or precision.
The score of finger and hand strokes is the average number of hits in five 10-second trials.
Abnormal trials from the fastest to the slowest range of more than 5 points were not discarded.
Each subject was subjected to three trials of coin rotation and grip force tasks for each hand.
However, the nail plate test for the groove is performed only once per hand, while the finger and hand-held tapping test for each hand is performed five times.
Each subject was tested in a balanced order in all exercise tests, starting with the dominant hand and alternating between the hands.
In order to allow direct comparison of motion tasks between the RHD and LHD groups, the data is converted to a standard score of mean 0 and standard deviation (SD)
1 Based on the performance of the control object.
The normalization of motion tasks is the means and SD based on the control objects of each motion task (Z score = (
Mean of the performance of subjects with control lesions)Control/SD)
SD lower than the control group indicated the damage in the lesion group (
Z score = 0 in the control group;
See Figure 1 and Figure 2).
This normalization was also carried out in order to be able to compare performance between task requirements.
In order to explore the hand differences in motion performance between LHD and RHD groups, asymmetric indices were derived.
In this study, the manual asymmetry of each subject was calculated using the formula preferred right hand (R)minus non-
Preferred left hand (L)
Divided by the preferred right hand ((R−L)/R)
For sports tasks, positive scores indicate better performance for the first player.
Download figureOpen in the new tabDownload powerpoint figure 1 motor task standardized Z score for the left hemisphere impaired group.
Download figureOpen in the new tabDownload powerpoint figure 2 to standardize the Z score for the exercise tasks of the right hemisphere impaired group.
Results: there were significant differences in grip strength between the two groups for R preference (F(2, 85)=12. 9, p