Date of download: 5/27/2016 Copyright © 2016 SPIE. All rights reserved. The block diagram of tolerance test protocol. Figure Legend: From: Application of functional data analysis in classification and clustering of functional near-infrared spectroscopy signal in response to noxious stimuli J. Biomed. Opt. 2016;21(10): doi: /1.JBO

Date of download: 5/27/2016 Copyright © 2016 SPIE. All rights reserved. Placement of NIRS probes on a subject’s forehead. Six photodetectors collect the data for 6 channels. Channels 1 (right) and 4 (left) are in near distance from the sources and channels 2, 3 (right) and 5, 6 (left) are in far distance from the sources. Figure Legend: From: Application of functional data analysis in classification and clustering of functional near-infrared spectroscopy signal in response to noxious stimuli J. Biomed. Opt. 2016;21(10): doi: /1.JBO

Date of download: 5/27/2016 Copyright © 2016 SPIE. All rights reserved. Boxplots and histogram of subjects self-reported pain scores: (a) boxplots in four different temperatures, and (b) histogram. We used the thresholds 6.5 and lower for low-pain (44%) and 8 and higher for high-pain (56%) groups. Figure Legend: From: Application of functional data analysis in classification and clustering of functional near-infrared spectroscopy signal in response to noxious stimuli J. Biomed. Opt. 2016;21(10): doi: /1.JBO

Date of download: 5/27/2016 Copyright © 2016 SPIE. All rights reserved. Effect of using different orders for B-spline bases. B-spline basis (left), a sample HB signal estimated by 10 bases (right): (a) B- spline order 1, (b) B-spline order 2, (c) B-spline order 3, and (d) B-spline order 4. Figure Legend: From: Application of functional data analysis in classification and clustering of functional near-infrared spectroscopy signal in response to noxious stimuli J. Biomed. Opt. 2016;21(10): doi: /1.JBO

Date of download: 5/27/2016 Copyright © 2016 SPIE. All rights reserved. GCV method was used to find the optimum smoothing parameter for each trial. Figure Legend: From: Application of functional data analysis in classification and clustering of functional near-infrared spectroscopy signal in response to noxious stimuli J. Biomed. Opt. 2016;21(10): doi: /1.JBO

Date of download: 5/27/2016 Copyright © 2016 SPIE. All rights reserved. The effect of choosing a different number of basis (B-spline order 4): (a) 5 bases, (b) 10 bases, (c) 20 bases, and (d) 30 bases. Figure Legend: From: Application of functional data analysis in classification and clustering of functional near-infrared spectroscopy signal in response to noxious stimuli J. Biomed. Opt. 2016;21(10): doi: /1.JBO

Date of download: 5/27/2016 Copyright © 2016 SPIE. All rights reserved. RFE_SVM feature selection classification accuracy with FDA data. Basis=10, (a) using only near channels, (b) using only far channels, and (c) using all channels: First 15 coefficients which resulted in 94% accuracy are: (numbers in the parentheses show bases numbers which can be between 1 and 10, base 1 represents first 1/10 of the data, base 2 second 1/10 and so on): Far_left_Hb(10), Near_left_HbO2(10), Far_right_Hb(1), Far_left_HbO2(5), Far_left_Hb(1) Near_left_HbO2(4), Near_left_Hb(3), Far_right_Hb(7), Near_left_HbO2(2), Far_right_HbO2(4)Near_right_HbO2(7), Far_left_Hb(9), Far_right_HbO2(5), Near_left_HbO2(1), Near_left_Hb(2). Figure Legend: From: Application of functional data analysis in classification and clustering of functional near-infrared spectroscopy signal in response to noxious stimuli J. Biomed. Opt. 2016;21(10): doi: /1.JBO

Date of download: 5/27/2016 Copyright © 2016 SPIE. All rights reserved. HBO2 and HB curves for channel 5 and channel 6 (far channels on the left side) using 30 bases. First 30 numbers are coefficients for Channel 5 HbO2 signal, 31 to 60 are coefficients for Channel 5 Hb signal, 61 to 90 are coefficients for Channel 6 HbO2 signal, and 91 to 120 are coefficients for Channel 6 Hb signal. Low-pain and high-pain signals are shown in blue and red, respectively. Figure Legend: From: Application of functional data analysis in classification and clustering of functional near-infrared spectroscopy signal in response to noxious stimuli J. Biomed. Opt. 2016;21(10): doi: /1.JBO

Date of download: 5/27/2016 Copyright © 2016 SPIE. All rights reserved. Clustering of painful (P) and not-painful signals (N) based on their HBO2 fDA curves. Figure Legend: From: Application of functional data analysis in classification and clustering of functional near-infrared spectroscopy signal in response to noxious stimuli J. Biomed. Opt. 2016;21(10): doi: /1.JBO

Date of download: 5/27/2016 Copyright © 2016 SPIE. All rights reserved. Mean and error bars for channel 6 (far left) HbO2 curves: (a) painful stimuli cluster 1, (b) nonpainful stimuli, and (c) painful stimuli cluster 2. Figure Legend: From: Application of functional data analysis in classification and clustering of functional near-infrared spectroscopy signal in response to noxious stimuli J. Biomed. Opt. 2016;21(10): doi: /1.JBO