ORCID Profile
0000-0002-9072-5122
Current Organisations
Lithuanian Sports University
,
KU Leuven
Does something not look right? The information on this page has been harvested from data sources that may not be up to date. We continue to work with information providers to improve coverage and quality. To report an issue, use the Feedback Form.
Publisher: Public Library of Science (PLoS)
Date: 28-02-2014
Publisher: Elsevier BV
Date: 03-2009
DOI: 10.1016/J.BRAINRES.2009.01.023
Abstract: The study examined the neurophysiological correlates of age-related changes in the coordination of hand and foot movements. Young and older adults (N=30) performed cyclical isodirectional and non-isodirectional hand-foot movements with contralateral and ipsilateral limb combinations. Motor evoked potentials (MEPs) and silent period durations following transcranial magnetic stimulation (TMS) were measured from the right extensor carpi radialis (ECR) muscle during the interlimb coordination tasks. Older adults demonstrated lower coordination stability than younger adults, particularly when performing non-isodirectional movements with ipsilateral limbs. For all coordination tasks, MEP litude was lower in older compared with young participants. Young adults showed significantly longer silent period durations when the coordination pattern involved ipsilateral limbs than during contralateral limb coordination. In contrast, silent period durations did not differ between contralateral and ipsilateral limb coordination in older adults. These results suggest that deterioration in motor performance with advancing age may be associated with a decreased ability to modulate inhibitory function.
Publisher: Elsevier BV
Date: 06-2014
DOI: 10.1016/J.NEUBIOREV.2014.04.001
Abstract: The ability to inhibit actions, one of the hallmarks of human motor control, appears to decline with advancing age. Evidence for a link between changes in inhibitory functions and poor motor performance in healthy older adults has recently become available with transcranial magnetic stimulation (TMS). Overall, these studies indicate that the capacity to modulate intracortical (ICI) and interhemispheric (IHI) inhibition is preserved in high-performing older in iduals. In contrast, older in iduals exhibiting motor slowing and a declined ability to coordinate movement appear to show a reduced capability to modulate GABA-mediated inhibitory processes. As a decline in the integrity of the GABA-ergic inhibitory processes may emerge due to age-related loss of white and gray matter, a promising direction for future research would be to correlate in idual differences in structural and/or functional integrity of principal brain networks with observed changes in inhibitory processes within cortico-cortical, interhemispheric, and/or corticospinal pathways. Finally, we underscore the possible links between reduced inhibitory functions and age-related changes in brain activation patterns.
Publisher: Elsevier BV
Date: 04-2016
DOI: 10.1016/J.CORTEX.2016.02.007
Abstract: Even though it has been suggested that the dorsolateral prefrontal cortex (DLPFC) and dorsal premotor cortex (PMd) are highly involved in the planning of bimanual movements, the exact nature (facilitatory or inhibitory) of their role is not well understood. Using a dual-site transcranial magnetic stimulation (TMS) paradigm, we examined the functional influence from DLPFC and PMd to the contralateral primary cortex (M1) during the preparation of a complex bimanual coordination task in which inter-hand movement frequency was manipulated. Only the left PMd showed inter-hand frequency-specific modulations in the interaction with the contralateral M1. Left PMd-right M1 interaction became facilitatory during the preparation phase when the left hand had to move faster than the right hand, while inhibitory modulation was observed when the movement frequency arrangement was reversed. Interestingly, bilateral DLPFC showed a facilitatory interaction with the contralateral M1s during the preparation period only in difficult conditions, irrespective of the inter-hand frequency ratio, suggesting a less task-specific role in the organization of complex bimanual actions. Observed task-related modulations in DLPFC-M1 and left PMd-right M1 interactions during preparation were significantly correlated with up-coming performance, predicting successful bimanual movements. These observations highlight the distinct roles of DLPFC and left PMd in the preparation of bimanual movements that require a differential contribution of each limb.
Publisher: Society for Neuroscience
Date: 10-02-2016
DOI: 10.1523/JNEUROSCI.3355-15.2016
Abstract: Changes in both brain structure and neurophysiological function regulating homotopic as well as heterotopic interhemispheric interactions (IHIs) are assumed to be responsible for the bimanual performance deficits in older adults. However, how the structural and functional networks regulating bimanual performance decline in older adults, as well as the interplay between brain structure and function remain largely unclear. Using a dual-site transcranial magnetic stimulation paradigm, we examined the age-related changes in the interhemispheric effects from the dorsolateral prefrontal cortex and dorsal premotor cortex onto the contralateral primary motor cortex (M1) during the preparation of a complex bimanual coordination task in human. Structural properties of these interactions were assessed with diffusion-based fiber tractography. Compared with young adults, older adults showed performance declines in the more difficult bimanual conditions, less optimal brain white matter (WM) microstructure, and a decreased ability to regulate the interaction between dorsolateral prefrontal cortex and M1. Importantly, we found that WM microstructure, neurophysiological function, and bimanual performance were interrelated in older adults, whereas only the task-related changes in IHI predicted bimanual performance in young adults. These results reflect unique interactions between structure and function in the aging brain, such that declines in WM microstructural organization likely lead to dysfunctional regulation of IHI, ultimately accounting for bimanual performance deficits. SIGNIFICANCE STATEMENT The structural and functional changes in the aging brain are associated with a decline in movement control, compromising functional independence. We used MRI and noninvasive brain stimulation techniques to investigate white matter microstructural organization and neurophysiological function in the aging brain, in relation to bimanual movement control. We found that less optimal brain microstructural organization and task-related modulations in neurophysiological function resulted in poor bimanual performance in older adults. By interrelating brain structure, neurophysiological function, and behavior, the current study provides a comprehensive picture of biological alterations in the aging brain that underlie declines in bimanual performance.
Publisher: Elsevier BV
Date: 03-2017
DOI: 10.1016/J.NEUROBIOLAGING.2016.11.012
Abstract: Functional motor declines that often occur with advancing age-including reduced efficacy to learn new skills-can have a substantial impact on the quality of life. Recent studies using noninvasive brain stimulation indicate that priming the corticospinal system by lowering the threshold for the induction of long-term potentiation-like plasticity before skill training may facilitate subsequent skill learning. Here, we used "priming" protocol, in which we used transcranial direct current stimulation (tDCS) applying the cathode over the primary motor cortex (M1) before the anode placed over M1 during unimanual isometric force control training (FORCE
Publisher: Cold Spring Harbor Laboratory
Date: 05-05-2023
DOI: 10.1101/2023.05.03.539327
Abstract: The efficacy of transcranial alternating current stimulation (tACS) is thought to be brain state-dependent, such that tACS during task performance would be hypothesised to offer greater potential for inducing beneficial electrophysiological changes in the brain and associated behavioural improvement compared to tACS at rest. However, to date, no empirical study has directly tested this postulation. Here we compared the effects of tACS applied during a stop signal task (online) to the effects of the same tACS protocol applied prior to the task (offline) and a sham control stimulation. A total of 53 young, healthy adults (32 female 18-35 yrs) received dual-site beta tACS over the right inferior frontal gyrus (rIFG) and pre-supplementary motor area (preSMA), which are thought to play critical roles in action cancellation, with phase-synchronised stimulation for 15 min with the aim of increasing functional connectivity. EEG connectivity analysis revealed significantly increased task-related functional connectivity following online but not offline tACS. Correlation analyses suggested that an increase in functional connectivity in the beta band at rest following online tACS was associated with an improvement in response inhibition. Interestingly, despite the lack of changes in functional connectivity at the target frequency range following offline tACS, significant improvements in response inhibition were still observed, suggesting offline tACS may still be efficacious in inducing behavioural changes, likely via a post-stimulation early plasticity mechanism. Overall, the results indicate that online and offline dual-site beta tACS are beneficial in improving inhibitory control via distinct underlying mechanisms.
No related grants have been discovered for Oron Levin.