Distinct Emotion Theory – Physiological Arousal

SNS/PNS Changes. In general, the three self-conscious emotions cause SNS activation.  A physiological change specific to embarrassment is blushing.

In one  study (Freed & D’Andrea, 2015), researchers investigated how the ANS changes during self-conscious emotions.  In this study, the physiology of 25 female participants diagnosed with PTSD was taken at baseline and during a slideshow.   The slides included 12 trauma-related images pertaining to the event that caused the PTSD.  After viewing each slide, participants reported the amount of fear/anxiety and shame/guilty they felt. Two minutes after the slideshow ended, participants self-reported their emotional states again.  Dependent variables included a measures of respiratory sinus arrythmia (RSA) and skin conductance level (SCL).  In this study, when shame/guilt was elicited by the trauma slides, participants showed in a reduction in RSA but no change in SCL and these findings held in the 2-minute period after the slides ended.  Similarly, when participants reported fear/anxiety after the slides, their RSA decreased and their SCL did not change. Although these findings suggest guilt/shame and fear/anxiety cause PNS deactivation and no change in SNS, they should be taken with caution due to the small sample size.  But, other research (Gerlach et al., 2003) tasked healthy controls and social phobic individuals to watch a video of themselves singing a song in front of other people.  During the video, RSA did not change  for either group but skin conductance and heart rate increased, suggesting embarrassment causes SNS activation but no changes in the PNS system.  Blushing, a physiological change experienced during embarrassment is caused by SNS activation .  When we blush, the SNS opens our blood vessels in our face, neck, and ears essentially overflowing these areas with blood, causing a red and hot face! Even Darwin (1872) identified blushing as an important indication of emotions describing blushing as “the most peculiar and most human of all expressions” (1872, p. 310).

Kreibig’s review (2010, study described here) included a meta-analysis of physiological changes of embarrassment.  Kreibig states that eliciting embarrassment in the laboratory typically includes humiliating the participants, asking participants to watch a video of themselves singing, or even imagining an embarrassing situation.  These eliciting events resulted in SNS activation and PNS withdrawal (see Table 8).  But Kreibig does point out that too few studies have been conducted on physiological chances in embarrassment to draw any definitive conclusions.  In conclusion, research suggests that self-conscious emotions cause SNS activation and either PNS deactivation or no changes in PNS activity.