Complexity analysis of fNIRS signals in ADHD children during working memory task

Figure 1. fNIRS activation maps for 0-back condition (A) and 1-back condition (B). The beta values are indicated by color. The light colors represent strong cortical activations, and vice versa. Bar plots of beta values showing the beta values of channel 3 in each conditions for the ADHD and control group (C). Error bars represent the standard error of the mean. *p < 0.05; **p < 0.01.

Figure 2. PE maps for the 0-back condition (A) and 1-back condition (B). The PE values are indicated by color. The light colors represent large PE values (high complexity), and vice versa. Bar plots of PE values showing the PE values of channel 3 in each conditions for the ADHD and control group (C). Error bars represent the standard error of the mean. *p < 0.05.

Figure 3. Scatter plots showing the correlation between the PE values and the cortical activations (A), and the ADHD index (B). The PE values were negatively correlated to the cortical activations (\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$r=-0.515$$\end{document}r=−0.515, \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$p=0.003$$\end{document}p=0.003) and positively correlated to the ADHD index (\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$r=0.448$$\end{document}r=0.448, \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek}…

Figure 4. Schematic of the experimental procedure. The order of the task conditions was random across subjects. The adjacent two tasks were separated by 30 s periods of rest. Just one possible order was shown in this figure.

Figure 5. Schematic arrangement of the fNIRS probe array. (A) Location of optodes (red = emitters; blue = detectors) and channels (numbers) over a standard brain model. (B) Anatomical areas covered by the probe array. Different colors represent different anatomical areas.

Figure 6. (A) Six motifs for the embedding dimension of 3. M represents motif. (B) A segment of fNIRS data used in this study. (C) The number of every order pattern at \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$m=2$$\end{document}m=2, 3, 4 and 5. Horizontal ordinate represents the order pattern. Vertical ordinate represents the number of the order pattern.