In concert with a growing awareness of the high prevalence and seriousness of social phobia have come questions about its diagnostic boundaries (Den Boer, 1997 and Stein, 1996). Of particular interest is the ambiguity surrounding social phobia’s distinction from normal shyness. Also, there is some popular concern that normative personality traits, such as shyness, are being pathologized (Stein, 1999).
A review of the literature has found that social phobia and shyness share many symptoms (see Henderson & Zimbardo, 2001; Turner, Beidel, & Townsley, 1990). Individuals who are shy and individuals with social phobia both experience heightened autonomic arousal in social situations (e.g., increased heart rate, blushing, sweating) (Beidel, Turner, & Dancu, 1985; Henderson, 1992 and Pilkonis, 1977). In addition, social skills deficits (e.g., limited eye contact, speech latencies), avoidance of social interactions, and cognitions reflecting fear of negative evaluation are characteristic of both groups (Heimberg et al., 1990, Herbert et al., 1992 and Ludwig and Lazarus, 1983; Zimbardo, 1977).
Although symptom profiles of social phobia and shyness overlap significantly, prevalence rates of the two constructs are different. Rates of shyness range from 40 to 50% (Carducci & Zimbardo, 1995; Zimbardo, 1977) while rates of social phobia range from 3 to 16% (Furmark et al., 1999 and Kessler et al., 1994; Wacker, Mullegans, Klein, & Battegay, 1992). Furthermore, at least 90% of college students report being shy at some point in their lives (Zimbardo, Pilkonis, & Norwood, 1975).
According to Turner et al. (1990), variables that may distinguish shyness from social phobia include severity of avoidance, level of impairment in social and occupational functioning, and course. More specifically, individuals who are shy report less avoidant behaviors and less impairment, and their symptoms often exhibit a transitory course compared to individuals with social phobia (Pilkonis, 1977; Schneier, Johnson, Hornig, Liebowitz, & Weissman, 1992; Turner, Beidel, & Larkin, 1986; Wells, Tien, Garrison, & Eaton, 1994). Differences between shyness and social phobia also may be explained by conceptualizing shyness subgroups. For example, Zimbardo (1977) proposed that there are two types of shy individuals; (1) shy introverts who prefer to be alone and lack social skills and, (2) shy extraverts who desire to interact with others, but lack social skills and experience internal distress and cognitive distortions about social situations. Similarly, Pilkonis (1977) divided shy individuals into publicly shy and privately shy subgroups. Using these conceptualizations, it may be that certain shyness subgroups are more likely to manifest social phobia than others.
Although it is easy to infer that shyness and social phobia are related, the empirical nature of this relationship remains unclear. Currently, there is only one study that presents data regarding the distribution of social phobia among highly shy individuals. St. Lorant, Henderson, and Zimbardo (2000) retrospectively reviewed charts of 114 patients presenting for treatment at a shyness clinic and reported that 97% of their sample had a generalized social phobia diagnosis. The rate of avoidant personality disorder, a disorder that is frequently comorbid with social phobia (Fahlen, 1995 and Herbert et al., 1992; Holt et al., 1992 and Schneier et al., 1991), was 67.1%.
In order to further conceptualize this relationship, a spectrum of shyness has been hypothesized (McNeil, 2001 and Stein, 1999). In this spectrum there are gradations of shyness: “average” levels of shyness are considered normative and are placed at one end of a continuum of severity while higher levels of shyness are proposed to merge with clinical disorders including, in order of severity, nongeneralized social phobia, generalized social phobia, and avoidant personality disorder (see Fig. 1). Additional data collected from a normative (as opposed to a treatment-seeking) sample are necessary to appreciate the dimensions of this hypothesized spectrum.
