Cotroneo Silvia Federica, Ala-Salomäki Heidi, Parkkonen Lauri, Liljeström Mia, Salmelin Riitta
Department of Neuroscience and Biomedical Engineering, Aalto University, Espoo, Finland.
Aalto NeuroImaging, Aalto University School of Science, Aalto, Finland.
Imaging Neurosci (Camb). 2024 Jun 5;2. doi: 10.1162/imag_a_00182. eCollection 2024.
Reliable individual-level measures of neural activity are essential for capturing interindividual variability in brain activity recorded by magnetoencephalography (MEG). While conventional group-level analyses highlight shared features in the data, individual-level specificity is often lost. Current methods for assessing reproducibility of brain responses focus on group-level statistics and neglect subject-specific temporal and spatial characteristics. This study proposes a combined ICA algorithm (comICA), aimed at extracting within-individual consistent MEG evoked responses. The proposed hypotheses behind comICA are based on the temporal profiles of the evoked responses, the corresponding spatial information, as well as independence and linearity. ComICA is presented and tested against simulated data and test-retest recordings of a high-level cognitive task (picture naming). The results show high reliability in extracting the shared activations in the simulations (success rate >93%) and the ability to successfully reproduce group-level results on reproducibility for the test-retest MEG recordings. Our model offers means for noise reduction, targeted extraction of specific activation components in experimental designs, and potential integration across different recordings.
可靠的个体水平神经活动测量对于捕捉脑磁图(MEG)记录的大脑活动中的个体间变异性至关重要。虽然传统的组水平分析突出了数据中的共同特征,但个体水平的特异性往往会丧失。当前评估大脑反应可重复性的方法侧重于组水平统计,而忽略了个体特定的时间和空间特征。本研究提出了一种组合独立成分分析算法(comICA),旨在提取个体内部一致的MEG诱发反应。comICA背后提出的假设基于诱发反应的时间轮廓、相应的空间信息以及独立性和线性。本文介绍了comICA,并针对模拟数据和一项高级认知任务(图片命名)的重测记录进行了测试。结果表明,在模拟中提取共享激活方面具有高可靠性(成功率>93%),并且能够在重测MEG记录的可重复性方面成功重现组水平结果。我们的模型提供了降噪手段、在实验设计中针对性提取特定激活成分的方法以及跨不同记录进行潜在整合的能力。