**Author details**

**3. Conclusion**

112 Drug Addiction

emotion regulation of the ANS for IA abusers.

**Acknowledgements**

assisting this study.

IA is a hot and serious issue worldwide, and psychophysiological relationship between emotion and IA using physiological signals was studied. This study was not only a hypothesis testing research, but also a hypothesis generating research. Emotion and physiological signals play important roles in (dynamic) expression and regulation of emotional responses to IA. Emotional induction experiments were conducted to acquire respiratory signals (thoracoabdominal movements), ECG signals, facial images, and self-assessed emotional intensity of IA abusers and IGD abusers. Complementary Ensemble Empirical Mode Decomposition (CEEMD) was also adopted as a feature extraction method for respiratory signals without phase loose or distortion. The power values, respiratory amplitude, of dominant frequency from thoracic movement and the abdominal movement in HIA and LIA groups were analyzed. The HIA group and the LIA group expressed different respiratory response upon positive and negative emotional inductions. The induction effects of emotional picture and film stimulation were also different. The autonomic nervous responses were also considered. RSA and HRV index computed from the ECG signals, reflected autonomic nervous system (ANS) activity, and particularly vagus nerve regulation (RSA reactivity). The results revealed that the HIA group had a lower RSA level than the LIA group. IA abusers (HIA) exhibited stronger RSA reactivity following negative emotion, but exhibited weaker RSA reactivity following positive emotion. The emotional responses of IGD abusers were also examined. IGD abusers had stronger happiness feelings to positive emotional online game films, and felt multiple negative emotions to negative emotional online game films. IGD abusers have more positive emotion, and stronger sympathetic activity, but weaker physiological activity to the online game films than those of people without IGD. This study provides results of respiration, HRV index, and RSA reactivity, the ANS and vagus nerve activity of IA abusers, and assists further study of the

This work was fully supported by the Taiwan Ministry of Science and Technology under Grant Numbers MOST 103-2221-E-009-139, MOST 105-2221-E-009-159, and MOST 105-2634- E-009-003. This work was also supported in part by the "Aim for the Top University Plan" of the National Chiao Tung University and Ministry of Education, Taiwan, R.O.C. This study was approved by the Institutional Review Board of the National Taiwan University Hospital Hsinchu Branch (Hsinchu, Taiwan), under the research project: A study of interactions between cognition, emotion and physiology (Contract No: 100IRB-32), and was approved by the Research Ethics Committee for Human Subject Protection of National Chiao Tung University (Hsinchu, Taiwan), Contract No: NCTU-REC-102-009-e. Thanks team members, Hong-Ming Ji, Shang-Chun Hsieh, Yi-Hua Huang, and Yao-Ming Wu, for Dai-Ling Hsieh<sup>1</sup> and Tzu-Chien Hsiao2 \*

\*Address all correspondence to: labview@cs.nctu.edu.tw

1 Institute of Computer Science and Engineering, National Chiao Tung University, Hsinchu, Taiwan

2 Institute of Biomedical Engineering, Department of Computer Science, National Chiao Tung University, Hsinchu, Taiwan
