The Hurst exponent of cardiac response to positive and negative emotional film stimuli using wavelet.

We examined the Hurst exponent of heart rate time series and its relation with the subjective measures of valence and arousal in two groups of subjects. The electrocardiogram (ECG) and the subjective valence and arousal were measured during the administration of emotional film stimuli (happiness, sadness, anger and fear). The results showed that there is a difference in the Hurst exponent for the happiness and sadness conditions but not between the negative emotion conditions (sadness, anger and fear). This seems to indicate that the Hurst exponent is an indicator of subjective valence.