Higher similarity in beta topography between tasks than subjects
- 111 Downloads
We have recently provided evidence for highly idiosyncratic topographic distributions of beta oscillations (as well as slow potentials) across individuals. More recently, by emphasizing the analysis of similarity instead of differences across tasks, we concluded that differences between an attention task and quiet resting may be negligible or at least unsystematic across subjects. Due to the possibility that individual differences could be due to noise in a wide sense or some inherent instability of beta activity, we designed a replication study to explicitly test whether pairs of individuals matched for head size and shape would still present less similar beta topography than each individual between sessions or tasks. We used independent component analysis (ICA) for an exhaustive decomposition of beta activity in a visual attention task and in quiet resting, recorded by 256-channel EEG in 20 subjects, on two separate days. We evaluated whether each ICA component obtained in one task and in one given individual could be explained by a linear regression model based on the topographic patterns of the complementary task (correlation between one component with a linear combination of components from complementary conditions), of the same task in a second session and of a matched individual. Results again showed a high topographic similarity between conditions, as previously seen between reasoning and simple visual attention beta correlates. From an overall number of 16 components representing brain activity obtained for the tasks (out of 60 originally computed where the remaining were considered noise), over 92% could satisfactorily be explained by the complementary task. Although the similarity between sessions was significantly smaller than between tasks on each day, the similarity between sessions was statistically higher than that between subjects in a highly significant way. We discuss the possible biases of group spatial averaging and the emphasis on differences as opposed to similarities, and noise in a wide sense, as the main causes of hardly replicable findings on task-related forms of activity and the inconclusive state of a universal functional mapping of cortical association areas.
KeywordsCortical function EEG Beta rhythm Individual variability Functional mapping
This work was supported by grant 2013/07236-0 from FAPESP (Fundação de Amparo à Pesquisa do Estado de São Paulo). We once more wish to thank Mauro de Salles Aguiar for his serious recognition of our work and most special support.
- Barch DM, Burgess GC, Harms MP, Petersen SE, Schlaggar BL, Corbetta M, Glasser MF, Curtiss S, Dixit S, Feldt C, Nolan D, Bryant E, Hartley T, Footer O, Bjork JM, Poldrack R, Smith S, Johansen-Berg H, Snyder AZ, Van Essen DC (2013) WU-Minn HCP Consortium. Function in the human connectome: task-fMRI and individual differences in behavior. Neuroimage 80:169–189. https://doi.org/10.1016/j.neuroimage.2013.05.033. (Epub 2013 May 16)CrossRefPubMedPubMedCentralGoogle Scholar
- Basile LF, Sato JR, Pasquini HA, Lozano MD, Nucci MP, Velasques B, Ribeiro P, Ramos RT, Anghinah R (2015) Individual topographic variability is inherent to cortical physiology but task-related differences may be noise. PLoS One 10(5):e0128343. https://doi.org/10.1371/journal.pone.0128343. (Erratum in: PLoS One)
- Finn ES, Shen X, Scheinost D, Rosenberg MD, Huang J, Chun MM, Papademetris X, Constable RT (2015) Functional connectome fingerprinting: identifying individuals using patterns of brain connectivity. Nat Neurosci 2015 Nov 18(11):1664–1671. https://doi.org/10.1038/nn.4135 (Epub 2015 Oct 12)Google Scholar
- Herholz K, Thiel A, Wienhard K, Pietrzyk U, von Stockhausen HM et al. (1996) Individual functional anatomy of verb generation. Neuroimage 3(3 Pt 1):185–194Google Scholar
- Noppeney U, Friston KJ, Price CJ (2004) Degenerate neuronal systems sustaining cognitive functions. J Anatomy Vol 205:6Google Scholar
- Pandya DN, Yeterian EH (1990) Prefrontal cortex in relation to other cortical areas in rhesus monkey: arquitecture and connections. Progress in brain research, vol 85. Uylings HBM, Van Eden CG, De Bruin JPC, Corner MA, Feenstra MGP. (eds). Elsevier Science Publishers BV. 63–94Google Scholar
- Pandya DN, Seltzer B, Barbas H (1988) Input-output organization of the primate cerebral cortex. Comp Primate Biol 4:39–80Google Scholar