Transdermal Optical Imaging Reveal Basal Stress via Heart Rate Variability Analysis: A Novel Methodology Comparable to Electrocardiography

Figures

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  FIGURE 1. Illustration of the skin structure and the skin color model.

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  FIGURE 2. Set up of study.

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  FIGURE 3. Placement of ECG electrodes on participants’ body.

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  FIGURE 4. Nine regions of interests (ROIs) illustrated on the face of Paul Zheng, an author of this paper. All participants, whose image have been used for this paper, signed a written informed consent for release of their images in published articles prior to inclusion of their image in this paper.

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  FIGURE 5. (A) Mean and standard deviation of participants’ heart rate obtained from TOI and BIOPAC. (B) Mean and standard deviation of participants’ stress from TOI and BIOPAC.

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  FIGURE 6. (A) Bland–Altman Plot comparing measures of heart rate obtained from TOI and BIOPAC. (B) Bland–Altman Plot comparing measures of stress obtained from TOI and BIOPAC.

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  FIGURE 7. (A) Measures of heart rate from TOI and BIOPAC. (B) Measure of stress from TOI and BIOPAC.

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  FIGURE 8. Set up of TOI station with Kang Lee, a corresponding author of this paper, sitting as a participant. All participants, whose image have been used for this paper, signed a written informed consent for release of their images in published articles prior to inclusion of their image in this paper.