The Sex Differences In Regulating Unpleasantemotion By Expressive Suppression:Extraversion Matters

Life experiences and empirical studies both indicate that the effects of emotion regulations may be influenced by sex and extraversion.Males are less emotionally expressive in human’s daily communication and engage more emotion-expressive suppression than females, supported by a number of empirical studies. Using Emotion Regulation Questionnaire(ERQ), Gross and colleagues found that males scored significantly higher than females in suppression scales when investigating individual differences in emotional regulation. It is noteworthy that what these researches measured is the frequency of using suppression strategy, rather than how effective the suppression strategy regulates emotional reaction. Despite abundant researches showing more frequent suppression of emotional expressions in males than in females, there is no direct evidence showing that males are better than females in dampening negative emotions by expressive suppression. Prior studies have also indicated that the tendency of emotional expressiveness is moderated by personality trait like extraversion. It has been indicated that higher extraversion is associated with greater excitability, increased emotional expressivity and better convey of nonverbal emotional information. Consistent with these findings, there is recent evidence showing that high extraversion is associated with increased difficulty in the suppression of emotional displays. Therefore, this academic thesis conducted two studies to investigate the following two questions: the first studyexplored whether there is a male advantage in regulating negative emotion by expressive suppression. We hypothesized that Males were associated with significantly smaller LPP amplitudes during expressive suppression relative to attending conditions, whereas this emotion regulation effect was absent in females. In the second study, we added extraversion to explore the interaction of sex and extraversion in the expressive suppression.We hypothesized that LPP amplitudes of ambivert males are significantly smaller during expressive suppression compared to viewing conditions, and this amplitude reduction would be less prominent in ambivertfemales. By contrast, this emotion regulation effect is probably absent in extraverts, irrespective of sex, based on the studies mentioned above.In the first study, 35 participants(17 males, 18 females) performed a picture viewing task. The experiment included 4blocks which consisted of 2 viewing blocks and 2regulating blocks. In attending blocks, participants just attended to neutral or negative pictures; whereas, in regulating blocks, participants were instructed to intentionally suppress the expression of emotional responses to pictures of cognitively reappraise pictures(e.g. think of pictures objectively). Event-Related brain Potentials(ERP) were recorded for the presentation of pictures. In electrophysiological results, Late Positive Potential(LPP), a posterior-parietal positive slow ERP, showed significantly more pronounced amplitudes during attending to negative relative to neutral pictures. More importantly, we observed interaction effects of regulating strategies and sex in the amplitudes of middle(2000~3000 ms) and late(3000~4000 ms) LPP windows. Males were associated with significantly smaller LPP amplitudes during expressive suppression relative to attending conditions in the 2000~4000ms time window, whereas this emotion regulation effect was absent in females. By contrast, LPP amplitudes were similar for reappraisal and attending conditions in all time windows, irrespective of sex.Event-related potentials were recorded while participants(17 extravert males, 16 ambivert males, 18 extravert females and 17 ambivert females) were required to view neutral or negative pictures,or intentionally suppress the expression of emotional responses to unpleasant pictures. Late Positive Potential(LPP) amplitudes showed an extraversion-moderated sex difference in the 2000-3000 ms and the 3000-4000 ms time epochs. LPP amplitudes were decreased during suppression versus viewing condition in ambivert males, while this effect was absent in ambivert females. However, the LPP amplitudes of extraverts were similar for suppression and viewing conditions, irrespective of sex and timing.In conclusion, these findings suggest that sex and extraversion should be considered in understanding the emotional consequences of suppression strategies.