Whittaker Heather T, Khayyat Lina, Fortier-Lavallée Jessica, Laverdière Megan, Bélanger Carole, Zatorre Robert J, Albouy Philippe
Cognitive Neuroscience Unit, Montreal Neurological Institute, McGill University, Montréal, QC, Canada.
International Laboratory for Brain, Music and Sound Research (BRAMS) - Centre for Research on Brain Language and Music (CRBLM), Montreal, QC, Canada.
Front Neurosci. 2024 Apr 4;18:1355565. doi: 10.3389/fnins.2024.1355565. eCollection 2024.
Rhythmic transcranial magnetic stimulation (rhTMS) has been shown to enhance auditory working memory manipulation, specifically by boosting theta oscillatory power in the dorsal auditory pathway during task performance. It remains unclear whether these enhancements (i) persist beyond the period of stimulation, (ii) if they can accelerate learning and (iii) if they would accumulate over several days of stimulation. In the present study, we investigated the lasting behavioral and electrophysiological effects of applying rhTMS over the left intraparietal sulcus (IPS) throughout the course of seven sessions of cognitive training on an auditory working memory task.
A limited sample of 14 neurologically healthy participants took part in the training protocol with an auditory working memory task while being stimulated with either theta (5 Hz) rhTMS or sham TMS. Electroencephalography (EEG) was recorded before, throughout five training sessions and after the end of training to assess to effects of rhTMS on behavioral performance and on oscillatory entrainment of the dorsal auditory network.
We show that this combined approach enhances theta oscillatory activity within the fronto-parietal network and causes improvements in auditoryworking memory performance. We show that compared to individuals who received sham stimulation, cognitive training can be accelerated when combined with optimized rhTMS, and that task performance benefits can outlast the training period by ∼ 3 days. Furthermore, we show that there is increased theta oscillatory power within the recruited dorsal auditory network during training, and that sustained EEG changes can be observed ∼ 3 days following stimulation.
The present study, while underpowered for definitive statistical analyses, serves to improve our understanding of the causal dynamic interactions supporting auditory working memory. Our results constitute an important proof of concept for the potential translational impact of non-invasive brain stimulation protocols and provide preliminary data for developing optimized rhTMS and training protocols that could be implemented in clinical populations.
节律性经颅磁刺激（rhTMS）已被证明可增强听觉工作记忆操作，特别是通过在任务执行期间提高背侧听觉通路中的θ振荡功率来实现。目前尚不清楚这些增强效果是否（i）在刺激期之后持续存在，（ii）是否可以加速学习，以及（iii）是否会在数天的刺激过程中累积。在本研究中，我们调查了在七节认知训练课程中，对左侧顶内沟（IPS）施加rhTMS对听觉工作记忆任务的持久行为和电生理影响。
14名神经健康的参与者组成的有限样本参加了听觉工作记忆任务的训练方案，同时接受θ（5Hz）rhTMS或假TMS刺激。在训练前、整个五次训练过程中以及训练结束后记录脑电图（EEG），以评估rhTMS对行为表现和背侧听觉网络振荡夹带的影响。
我们表明，这种联合方法增强了额顶网络内的θ振荡活动，并改善了听觉工作记忆表现。我们表明，与接受假刺激的个体相比，结合优化的rhTMS可以加速认知训练，并且任务表现的益处可以在训练期后持续约3天。此外，我们表明训练期间招募的背侧听觉网络内的θ振荡功率增加，并且在刺激后约3天可以观察到EEG的持续变化。
本研究虽然样本量不足以进行确定性的统计分析，但有助于增进我们对支持听觉工作记忆的因果动态相互作用的理解。我们的结果构成了非侵入性脑刺激方案潜在转化影响的重要概念验证，并为开发可在临床人群中实施的优化rhTMS和训练方案提供了初步数据。
