| Records |
| Author |
Friedman, J.; Amiaz, A.; Korman, M. |
| Title |
The online and offline effects of changing movement timing variability during training on a finger-opposition task |
Type  |
Journal Article |
| Year |
2022 |
Publication |
Scientific Reports |
Abbreviated Journal |
Sci Rep |
| Volume |
12 |
Issue |
1 |
Pages |
13319 |
| Keywords |
Fingers; Humans; *Learning; *Motor Skills; Movement; Psychomotor Performance; Upper Extremity |
| Abstract |
In motor learning tasks, there is mixed evidence for whether increased task-relevant variability in early learning stages leads to improved outcomes. One problem is that there may be a connection between skill level and motor variability, such that participants who initially have more variability may also perform worse on the task, so will have more room to improve. To avoid this confound, we experimentally manipulated the amount of movement timing variability (MTV) during training to test whether it improves performance. Based on previous studies showing that most of the improvement in finger-opposition tasks comes from optimizing the relative onset time of the finger movements, we used auditory cues (beeps) to guide the onset times of sequential movements during a training session, and then assessed motor performance after the intervention. Participants were assigned to three groups that either: (a) followed a prescribed random rhythm for their finger touches (Variable MTV), (b) followed a fixed rhythm (Fixed control MTV), or (c) produced the entire sequence following a single beep (Unsupervised control MTV). While the intervention was successful in increasing MTV during training for the Variable group, it did not lead to improved outcomes post-training compared to either control group, and the use of fixed timing led to significantly worse performance compared to the Unsupervised control group. These results suggest that manipulating MTV through auditory cues does not produce greater learning than unconstrained training in motor sequence tasks. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
|
Editor |
|
| Language |
English |
Summary Language |
|
Original Title |
|
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
2045-2322 |
ISBN |
|
Medium |
|
| Area |
|
Expedition |
|
Conference |
|
| Notes |
PMID:35922460; PMCID:PMC9349301 |
Approved |
no |
| Call Number |
|
Serial |
115 |
| Permanent link to this record |
| |
|
| |
| Author |
Lowenthal-Raz, J.; Liebermann, D.G.; Friedman, J.; Soroker, N. |
| Title |
Kinematic descriptors of arm reaching movement are sensitive to hemisphere-specific immediate neuromodulatory effects of transcranial direct current stimulation post stroke |
Type |
Journal Article |
| Year |
2024 |
Publication |
Scientific Reports |
Abbreviated Journal |
Sci Rep |
| Volume |
14 |
Issue |
1 |
Pages |
11971 |
| Keywords |
Humans; *Transcranial Direct Current Stimulation/methods; Male; Female; Middle Aged; *Stroke/physiopathology/therapy; Biomechanical Phenomena; Aged; *Arm/physiopathology; *Movement/physiology; *Stroke Rehabilitation/methods; Single-Blind Method; Cross-Over Studies |
| Abstract |
Transcranial direct current stimulation (tDCS) exerts beneficial effects on motor recovery after stroke, presumably by enhancement of adaptive neural plasticity. However, patients with extensive damage may experience null or deleterious effects with the predominant application mode of anodal (excitatory) stimulation of the damaged hemisphere. In such cases, excitatory stimulation of the non-damaged hemisphere might be considered. Here we asked whether tDCS exerts a measurable effect on movement quality of the hemiparetic upper limb, following just a single treatment session. Such effect may inform on the hemisphere that should be excited. Using a single-blinded crossover experimental design, stroke patients and healthy control subjects were assessed before and after anodal, cathodal and sham tDCS, each provided during a single session of reaching training (repeated point-to-point hand movement on an electronic tablet). Group comparisons of endpoint kinematics at baseline-number of peaks in the speed profile (NoP; smoothness), hand-path deviations from the straight line (SLD; accuracy) and movement time (MT; speed)-disclosed greater NoP, larger SLD and longer MT in the stroke group. NoP and MT revealed an advantage for anodal compared to sham stimulation of the lesioned hemisphere. NoP and MT improvements under anodal stimulation of the non-lesioned hemisphere correlated positively with the severity of hemiparesis. Damage to specific cortical regions and white-matter tracts was associated with lower kinematic gains from tDCS. The study shows that simple descriptors of movement kinematics of the hemiparetic upper limb are sensitive enough to demonstrate gain from neuromodulation by tDCS, following just a single session of reaching training. Moreover, the results show that tDCS-related gain is affected by the severity of baseline motor impairment, and by lesion topography. |
| Address |
Faculty of Medicine, Tel-Aviv University, Tel Aviv, Israel. nachum@soroker.online |
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
|
Editor |
|
| Language |
English |
Summary Language |
|
Original Title |
|
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
2045-2322 |
ISBN |
|
Medium |
|
| Area |
|
Expedition |
|
Conference |
|
| Notes |
PMID:38796610; PMCID:PMC11127956 |
Approved |
no |
| Call Number |
|
Serial |
125 |
| Permanent link to this record |
