آیا کمرویی و جامعه پذیری هنوز یک ترکیب خطرناکی برای استفاده از مواد مخدر است؟ مدارک و شواهد از ایالات متحده آمریکا و کانادا نمونه

A number of studies have suggested that shyness and sociability may be orthogonal dimensions of personality, each of which is associated with distinct behavioral and psychophysiological correlates, and that a combination of shyness and sociability may be a risk factor for illicit drug use. We examined whether self-reported shyness, sociability, and sensation seeking measures predicted substance use and substance use related behaviors in separate samples of undergraduates in the US and Canada. We found that a combination of shyness and sociability predicted substance use related behaviors in the US sample above and beyond either shyness or sociability alone, replicating and extending previous research. However, this pattern was not found for the Canadian sample. Interestingly, individuals in the Canadian sample who were low in shyness and low in sociability were likely to report high substance use. We also noted that individuals who scored high on measures of sensation seeking were likely to score high on substance use and substance use related behaviors across both samples, replicating previous work. Findings suggest that, while shyness alone may be a protective factor for substance use, a combination of shyness and sociability may be a possible risk factor for substance use and abuse in some cultural contexts.

Over the last 20 years, there has been a growing interest directed toward identifying personality correlates of substance use. The importance of identifying personality factors that predict substance use cannot be overlooked. Substance use in young adults and adolescents has been consistently associated with academic failure (Wills, Vaccaro, & McNamara, 1992), the loss of familial and interpersonal relationships (Newcomb & Earlywine, 1996; Stockwell, Hodgson, & Rankin, 1982), and delinquent behavior (Huizinga & Jakob-Chien, 1998; Loeber, Stouthamer-Loeber, & Raskin-White, 1999). Not surprisingly, the extant literature in the field is diverse. The range of research has included personality factors such as the five-factor model of personality (Gullone & Moore, 2000; Loukas, Krull, Chassin, & Carle, 2000), sensation-seeking (Liraud & Verdoux, 2000; Zuckerman & Kuhlman, 2000), social phobia (Lepine & Pelissolo, 1998), shyness and sociability (Page, 1990; Tucker et al., 1995), behavioral inhibition (Sher, Bartholow, & Wood, 2000), and other anxiety disorders (Kushner, Sher, & Erickson, 1999; Lewis & O’Neill, 2000). However, there appears to be little to no agreement concerning the extent to which these diverse factors contribute to substance use and abuse. Furthermore, few studies have extended the research focus beyond any one particular personality factor. There are some personality styles that have been implicated in risk-taking behaviors and substance use more so than others. For example, the relation between individual differences in sensation seeking and substance use is ubiquitous. Sensation seeking can be described as seeking “novel, complex, and intense sensations and experiences, and the willingness to take physical, legal, social and financial risks for the sake of such experiences” (Zuckerman, 1994). Zuckerman argued that individuals scoring high on measures of sensation seeking anticipate positive arousal from participating in risky behaviors. Several studies have independently shown that sensation seeking was associated with high alcohol consumption (Johnson, 1989; Lagrange, Jones, Erb, & Reyes, 1995) and illicit drug use (Zuckerman, 1994; Zuckerman, Neary, & Brustman, 1970). Although less well-documented, studies of the relation between shyness and related constructs (e.g., social anxiety and social phobia) and substance use are growing in research popularity. Hartman (1986), for example, reported that a significantly higher proportion of shy than non-shy individuals admitted using alcohol and drugs to lessen social anxiety. Similarly, social phobia patients often suffer from comorbid alcohol problems (Mannuzza et al., 1995) and report that alcohol lessens their fearfulness and anxiety in social situations (Smail, Stockwell, Canter, & Hodgson, 1984). The short-term anxiolytic effects of alcohol and some illicit substances have been well described (see, e.g., Kushner, Sher, & Beitman, 1990; Kushner et al., 1999; Sher, 1987). Researchers therefore argue that shy and socially anxious individuals often use substances and illicit drugs to “self-medicate”, serving as a coping mechanism for psychosocial difficulties (Arndt, Tyrell, Flaum, & Andreasen, 1992). However, others have failed to find a consistent relation between shyness and alcohol use (Cheek & Melchior, 1990; Leary & Kowalski, 1995). The studies described above have treated shyness as a unitary construct. Researchers have, however, long recognized that different forms of shyness exist, and that these may emerge as a result of differences in sociability (Asendorpf, 1990; Asendorpf & Meier, 1993; Cheek & Buss, 1981). For example, some individuals are quiet and reserved in social situations (i.e., they are introverts); others are quiet and inhibited in social situations because they are fearful (i.e., they are shy); and still others may be highly avoidant of social situations, but desire to affiliate with others, and these individuals appear socially reticent and anxious because of an approach–avoidant conflict. Cheek and Buss (1981) examined the relation between shyness and sociability and demonstrated that the two dimensions were only modestly related; contrary to lay judgements, shyness is not merely low sociability. Individuals scoring high on measures of shyness did not necessarily report low sociability. Cheek and Buss also noted that some highly shy individuals varied on measures of sociability, and combinations of these two factors were related to distinct behavioral manifestations. For example, Cheek and Buss found that high shy/high social individuals exhibited more overt behavioral anxiety and appeared interpersonally impaired during social interactions compared with high shy/low social and low shy groups. This view has been supported in studies of children as well (e.g., Coplan, Rubin, Fox, Calkins, & Stewart, 1994). In addition, other work by Schmidt and his colleagues (Schmidt, 1999; Schmidt and Fox, 1994 and Schmidt and Fox, 1995) has noted that shyness and sociability are distinguishable on measures of central (i.e., regional EEG) and autonomic (i.e., heart rate) psychophysiology, and that high shy/high social individuals (i.e., the conflicted group) are distinguishable from the other three high and low combinations of shyness and sociability on these measures. Despite this growing corpus of research, little research attention has been directed toward understanding the contribution of both shyness and sociability to substance use and abuse. Over a decade ago, Page (1990) used the Cheek and Buss (1981) measurement model of shyness and sociability to understand personality risk factors that predict illicit substance use in a sample of male adolescents. He reasoned that high shy/high social individuals were at an increased risk for substance use because these behaviors may help them cope with an approach–avoidance conflict that they experience during and/or in anticipation of social interactions. Page found that males scoring high on measures of shyness were significantly more likely to use illicit substances than those low on measures of shyness. Furthermore, adolescents scoring high on both shyness and sociability reported significantly more use of hallucinogenic substances and slightly more use of cocaine and marijuana compared with other combinations of shyness and sociability. Page suggested that, although shyness alone was an important risk factor, shyness in combination with sociability further increased the risk for substance use. He argued that these individuals might resort to substance use in an attempt to overcome interpersonal impairment as suggested by Cheek and Buss (1981). More recently, however, a study investigating alcohol dependence and shyness in a sample of US Navy men found that, while shy males consumed alcohol in order to “reduce social awkwardness and anxiety”, no differences were found in regards to reported sociability ( Mann, 2000), suggesting that the relation among shyness, sociability, and substance use is not a foregone conclusion. Overall, there were two goals of the present study. The primary goal was to extend the Cheek and Buss (1981) measurement model on the relative independence of shyness and sociability to substance use measures in young adults in separate countries, and in so doing, also clarify previous literature on whether a combination of shyness and sociability is a risk factor for substance use. A second goal was an attempt to extend and clarify inconsistencies in the extant literature on the role that personality, in general, plays in substance use by considering several different measures of personality.