Evaluating valence level of pictures stimuli in heart rate variability response

Low and high valence were induced in 20 male volunteers using two groups of pictures stimuli. Heart response was compared between two groups from RR series extracted from recorded ECG measurements. Mean heart rate and heart rate variability measures including time, frequency and Poincare domain were extracted. The results revealed that HRV triangular index, SDNN and SD2 were the only statistically significant parameters between groups (p<;0.05). Mean heart rate and power in LF and HF bands were also different between low and high valence groups however level of significance was not reached..