A1 Journal article (refereed)
Optimal Number of Clusters by Measuring Similarity Among Topographies for Spatio-Temporal ERP Analysis (2022)

Mahini, R., Xu, P., Chen, G., Li, Y., Ding, W., Zhang, L., Qureshi, N. K., Hämäläinen, T., Nandi, A. K., & Cong, F. (2022). Optimal Number of Clusters by Measuring Similarity Among Topographies for Spatio-Temporal ERP Analysis. Brain Topography, 35(5-6), 537-557. https://doi.org/10.1007/s10548-022-00903-2

JYU authors or editors

Publication details

All authors or editors: Mahini, Reza; Xu, Peng; Chen, Guoliang; Li, Yansong; Ding, Weiyan; Zhang, Lei; Qureshi, Nauman Khalid; Hämäläinen, Timo; Nandi, Asoke K.; Cong, Fengyu

Journal or series: Brain Topography

ISSN: 0896-0267

eISSN: 1573-6792

Publication year: 2022

Publication date: 18/07/2022

Volume: 35

Issue number: 5-6

Pages range: 537-557

Publisher: Springer Science and Business Media LLC

Publication country: United States

Publication language: English

DOI: https://doi.org/10.1007/s10548-022-00903-2

Publication open access: Not open

Publication channel open access: 

Web address of parallel published publication (pre-print): https://arxiv.org/abs/1911.09415

Additional information: Correction: DOI: 10.1007/s10548-022-00918-9

Abstract

Averaging amplitudes over consecutive time samples (i.e., time window) is widely used to calculate the peak amplitude of event-related potentials (ERPs). Cluster analysis of the spatio-temporal ERP data is a promising tool to determine the time window of an ERP of interest. However, determining an appropriate number of clusters to optimally represent ERPs is still challenging. Here, we develop a new method to estimate the optimal number of clusters utilizing consensus clustering. Various polarity dependent clustering methods, namely, k-means, hierarchical clustering, fuzzy c-means, self-organizing map, spectral clustering, and Gaussian mixture model, are used to configure consensus clustering after assessing them individually. When a range of clusters is applied many times, the optimal number of clusters should correspond to the expectation, which is the average of the obtained mean inner-similarities of estimated time windows across all conditions and groups converge in the satisfactory thresholds. In order to assess our method, the proposed method has been applied to simulated data and prospective memory experiment ERP data aimed to qualify N2 and P3, and N300 and prospective positivity components, respectively. The results of determining the optimal number of clusters meet at six cluster maps for both ERP data. In addition, our results revealed that the proposed method could be reliably applied to ERP data to determine the appropriate time window for the ERP of interest when the measurement interval is not accurately defined.

Keywords: cognitive neuroscience; imaging; EEG; signal analysis; signal processing; cluster analysis

Free keywords: event-related potentials; optimal number of clusters; topographical analysis; time window; microstates; consensus clustering

Contributing organizations

Ministry reporting: Yes

Reporting Year: 2022

JUFO rating: 1