Abstract:

Biological basis of social anxiety contained three correlated levels which were physiological reaction, hereditary association and evolutionary explanation. In terms of physiological reaction, social anxiety illustrated men had different characteristics in the three stages of expression. In the earlier identification stage, men had intensive alarm reaction to the expression of all types. The specific performance P1 was enlarged. The activation in bilateral occipital area was enhanced. In the mid-term awareness stage which was only sensitive to anger expression. The specific performance P2 was also enlarged. The activation of amygdala and cingulated cortex was enhanced. In the late reaction stage which had noticeable negative expression process bias. The specific performance of the later period ERPs, P3 was enlarged. The activation of frontal lobe enhanced caused the connection between central nervous system such as cingulo-opercular network and amygdale weakened. In hereditary association, social anxiety had the genetic phenomenon of parent-offspring transmission and high correlation. Besides that, it related to some genes such as 5-HTT, MAO-A, BDNF and DRD2. In evolutionary explanation, social anxiety was regarded as natural response and defense mechanism to social threat which could activate arousal levels which improved and helped the individual to mobilize the body respond to the threat. In addition, it could also impress the opposite sex to get mates which could increase the popularity of individual in groups which could help the individual get more chances of development.

Key words: social anxiety, physiological reaction, hereditary association, evolutionary explanation