Kaminski Elisabeth, Maudrich Tom, Bassler Pauline, Ordnung Madeleine, Villringer Arno, Ragert Patrick
Department of Movement Neuroscience, Faculty of Sport Science, Leipzig University, Leipzig, Germany.
Department of Neurology, Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany.
Front Aging Neurosci. 2022 Sep 20;14:935781. doi: 10.3389/fnagi.2022.935781. eCollection 2022.
Transferring a unimanual motor skill to the untrained hand, a phenomenon known as cross-limb transfer, was shown to deteriorate as a function of age. While transcranial direct current stimulation (tDCS) ipsilateral to the trained hand facilitated cross-limb transfer in older adults, little is known about the contribution of the contralateral hemisphere to cross-limb transfer. In the present study, we investigated whether tDCS facilitates cross-limb transfer in older adults when applied over the motor cortex (M1) contralateral to the trained hand. Furthermore, the study aimed at investigating short-term recovery of tDCS-associated cross-limb transfer. In a randomized, double-blinded, sham-controlled setting, 30 older adults (67.0 ± 4.6 years, 15 female) performed a short grooved-pegboard training using their left hand, while anodal (a-tDCS) or sham-tDCS (s-tDCS) was applied over right M1 for 20 min. Left (LH ) - and right-hand (RH ) performance was tested before and after training and in three recovery measures 15, 30 and 45 min after training. LH performance improved during both a-tDCS and s-tDCS and improvements persisted during recovery measures for at least 45 min. RH performance improved only following a-tDCS but not after s-tDCS and outlasted the stimulation period for at least 45 min. Together, these data indicate that tDCS over the M1 contralateral to the trained limb is capable of enhancing cross-limb transfer in older adults, thus showing that cross-limb transfer is mediated not only by increased bi-hemispheric activation.
将单手动运动技能转移到未受过训练的手上,即所谓的交叉肢体转移现象,已被证明会随着年龄的增长而变差。虽然对训练手同侧的经颅直流电刺激(tDCS)促进了老年人的交叉肢体转移,但对于对侧半球在交叉肢体转移中的作用知之甚少。在本研究中,我们调查了在训练手对侧的运动皮层(M1)上施加tDCS时,是否能促进老年人的交叉肢体转移。此外,该研究旨在调查与tDCS相关的交叉肢体转移的短期恢复情况。在一项随机、双盲、假对照试验中,30名老年人(67.0±4.6岁,15名女性)用左手进行了简短的带槽钉板训练,同时在右侧M1上施加阳极tDCS(a-tDCS)或假tDCS(s-tDCS),持续20分钟。在训练前后以及训练后15、30和45分钟的三项恢复测量中,测试了左手(LH)和右手(RH)的表现。在a-tDCS和s-tDCS期间,LH表现均有所改善,并且在恢复测量中至少持续45分钟。仅在a-tDCS后RH表现有所改善,而在s-tDCS后则没有,并且持续超过刺激期至少45分钟。总之,这些数据表明,在训练肢体对侧的M1上施加tDCS能够增强老年人的交叉肢体转移,从而表明交叉肢体转移不仅由双半球激活增加介导。