Fisoun, Virginia MSc; Floros, Georgios MD; Siomos, Konstantinos PhD; Geroukalis, Dimitrios PhD; Navridis, Klimis PhD
New technologies are gradually diffusing into people's daily lives, altering their way of thinking, behaving, and acting in an increasingly changing world. Research data have shown that this new modality of communicating and recreation can create psychosocial problems similar to those suffered by individuals demonstrating addictive behaviors (Griffiths, 2000; Kaltiala-Heino et al., 2004; Christakis, 2010).
Abusive or addictive behaviors emerge in various forms and relate to various patterns other than the use of psychoactive substances, including gambling, sex, compulsive buying, or stealing (Thombs, 2006). Even though there is a great amount of research data on the Internet addiction issues, as well as many surveys focusing on the inappropriate use or addiction to legal and/or illegal substances, the link between these 2 problematic behaviors has not been established. Internet addiction disorder as a concept is reportedly finding its place in the appendix of suggested disorders that require more research and testing in the forthcoming Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (Miller and Holden, 2010), because there have not been conclusive evidence to place it under the “addictive behaviors” category. Therefore, research on the existence of any correlates between well-established addiction paradigms and Internet addiction would be helpful to determine future classification. Until then, there is a significant research and clinical hurdle concerning the choice of relevant criteria for classifying a person as being addicted to the Internet. By applying typical criteria for substance abuse (American Psychiatric Association, 1994), Internet “dependence” would refer to a chronic progressive disease that includes a compulsive need for internet use with lack of related control and disregard over the obvious adverse consequences. Such a phenomenon would necessarily include the development of tolerance (demonstrated by the reduced psychotropic effect of ongoing use and a concomitant need to increase the level of use), some form of withdrawal effects (including psychological malaise and psychosomatic disturbances), a loss of the sense of time spent online, dedicating a large amount of time offline on ruminating on future use or actively attempting to find a way to connect, prioritizing online time over offline activities regardless of their importance, and continuing this excessive level of use despite clear indications of the negative consequences or attempts to self-limit Internet use.
PERSONALITY CORRELATES OF ADDICTIVE BEHAVIORS—A COMMON ROLE OF DOPAMINE
Personality inventories have been used in the field of addiction studies for some time to ascertain whether users of addictive drugs share some common characteristics. The oldest model is the Eysenck's PEN model under which there are 3 major dimensions of personality: P (psychoticism), E (extraversion), and N (neuroticism), covering different areas of personality (H.J. Eysenck and M.W. Eysenck, 1985). Studies involving hallucinogenic drugs, chemical-dependents, and drug addicts with the use of the Eysenck's Personality Questionnaire (EPQ) have consistently demonstrated a pattern of scoring dubbed “high addiction scores,” namely high scores on the psychoticism and neuroticism factors and low scores on the lie factor (P+, N+ and L−) (Gossop and Eysenck, 1980; Kirkcaldy et al., 2004). We should note that although the psychoticism and neuroticism factors have been postulated to have biological underpinnings, the lie factor was originally included to provide a reliability scale. However, the lie factor appears to correlate with the typically high degree of social immaturity of drug addicts. Furthermore, the neuroticism component in the addiction personality typology has been reported as possibly being artificially inflated during the course of drug addiction and contact with corresponding services, rather than being a primary finding (Gossop and Eysenck, 1980).
The initial hypothesis that individual variability in dopamine functioning represents a neurobiological substratum for the psychoticism personality dimension (Lester, 1989) was provided with biological evidence from studies on receptor binding with single-photon emission computed tomography (Gray et al.,1994) and replicated elsewhere with the use of both functional magnetic resonance imaging and evoked potentials (Kumari et al., 2004; O'Gorman et al., 2006; Colzato et al., 2009; Papageorgiou et al., 2010).
Dopamine functioning has been on the forefront of research on the biological underpinnings of addiction for some time. Although the central dopaminergic neurotransmission is complex, research findings point to the fact that a dysfunction of the dopamine transmission in the mesocorticolimbic reward pathway is associated with drug addiction (Bressan and Crippa, 2005). This system is critical for the acute rewarding effects of psychostimulant drugs and also has a more enabling function for all drugs of abuse (Koob and Volkow, 2009). The proposed dopamine hypothesis for addiction holds that since excessive dopamine functioning directly induced by psychostimulant use increases the incidence of addictive behaviors, individuals in whom inherent dopamine functioning is below par, and who typically present with high scores on the psychoticism factor of the PEN model, would be readily addicted to those types of behavior that are reinforcing, and will continue to indulge in these behaviors even after the circumstances giving rise to them have changed. Those individuals would be grouped as “addictive personalities.” (Eysenck, 1997; Dagher and Robbins, 2009). Research has long implicated the role of striatal dopaminergic system in the behavioral maladaptations associated with one addictive Internet behavior, video game playing (Koepp et al., 1998), and recent research has demonstrated that genetic polymorphisms of the dopaminergic system were more prevalent in individuals with excessive Internet video game playing an event that correlated with higher levels of reward dependence (Han et al., 2007).
PERSONALITY AND INTERNET ABUSE
A number of studies have suggested that certain personality traits correlate with online addictive behaviors. A study of 1471 adult online game users found that aggression and narcissistic personality traits were positively correlated with online game addiction (Kim et al., 2008). However, this model that included self-control, interpersonal relationships, and occupation only accounted for 20% of the variance in behavior. In a study of 752 Taiwanese high school students, Internet dependents scored significantly higher on overall sensation seeking and disinhibition than the Internet nondependents (Lin and Tsai, 2002). A study of 3662 Taiwanese high school students found that adolescents with Internet addiction were more likely to have substance use experience. High novelty seeking (NS), high harm avoidance (HA), and low reward dependence (RD) predicted a higher proportion of adolescents with Internet addiction, while high NS, low HA, and low RD predicted a higher proportion of adolescents with substance use experience (Ko et al., 2006). A survey of 2620 Chinese high school students examining a possible connection of chemical substance abuse and online addiction revealed that the Internet addiction group had significantly higher scores on the EPQ subscales of neuroticism, psychoticism, and lie than the control group (Cao and Su, 2007).
THE SITUATION IN GREECE REGARDING CHEMICAL SUBSTANCES AND INTERNET ADDICTION
The use of legal and illegal substances, especially among pupils, is a major public health issue in Greece. According to the results of the European School Survey Project on Alcohol and Other Drugs (ESPAD) research in 2007, 10% of the adolescents, aged between 14 and 17 years, stated that they have used an illegal substance at least once in their lives, whereas the use increases among the older adolescents (Hibell et al., 2009). With regards to the student population in Greece, the ESPAD study involved a nationwide sample of high school students aged 15 to 16 years. In 2007, 6% had ever tried marijuana or hashish. Inhalants' lifetime prevalence was reported by 9% of the students, while lifetime prevalence of amphetamines was reported by 3% of the sample, 2% reported ecstasy use, 2% reported LSD use as well. Results indicated a 5% yearly prevalence of cannabis use and a 3% prevalence of cannabis for the last month.
Recent large surveys have demonstrated the existence of Internet addiction as a health issue in Greece, with estimates of prevalence ranging from 8.2% in the 12 to 18 years age range (Siomos et al., 2008) to 11.6% in college students (Frangos and Kiohos, 2010). Efforts are being made to tackle the issue with the provision of specialized services (Siomos et al., 2010).
Goals and Research Hypotheses
The aim of this investigation is to study whether adolescent Internet abuse can be an important variable in the recognition of adolescent illegal substance use. Research hypothesis was formulated as follows: Increased levels of illicit substance use in the adolescent population would be correlated to increased levels of Internet abuse. An examination into the nature of an adolescent's Internet use would provide us with helpful information in determining whether there is an increased possibility of concurrent illicit substance use. This information would be nonredundant if we take into account sociodemographic factors such as offline activities, disruptive and antisocial behavior, and personality traits.
This study was of a cross-sectional design with a sample consisting of 1270 teen students between 14 and 19 years of age of the island of Kos, Greece. The survey sample includes all students of the last 4 grades of high school in the island. Kos island is located at the South Aegean sea, population is in the 30,000 range and is a major tourist destination during summertime. It is famous for being the birthplace of Hippocrates and cradle of Western Medicine. The study was designed by the Psychiatric Unit of the University of Thessaly in collaboration with the Drug abuse prevention center “Hippokrates” of the Greek Organization against Illicit Drugs (OKANA). Proper permission for the study was sought for and granted by the official governing body of the educational system. Thirteen schools participated in the study (7 Gymnasiums and 6 Lyceums, the former being the junior grade and the latter the senior grade of high school education in Greece). The research material was distributed in schools and participation was voluntary and confidential.
Forty-nine students (3.85%) declined to participate in the study and were excluded. There were 587 boys (48.3% of the sample, mean age 15.99 years, SE = 0.053) and 634 girls (51.7% of the sample, mean age 16.02 years, SE = 0.048). Gender and age distribution were similar. Sample demographics are presented in Table 1.
Participants had to fill in a general demographics questionnaire, which included questions on offline behaviors. Study design excluded individuals who were receiving treatment of any kind for overt psychopathology and a provision was made for the referral of any individuals coming forward with psychic complaints to the local mental health services. All questionnaires were administered by mental health professionals with an emphasis on confidentiality.
The demographics questionnaire is a modified version of the self-report research instrument employed by the American National Institute on Drug Abuse (Hawkins and Nederhood, 1987). The Greek adaptation was carried out by the Section for Research and Evaluation of the Greek Therapy Center for Dependent Individuals (KETHEA). It included questions on sex, age, parents' educational and occupational background, family's financial status, school performance, and related goals. Questions on behaviors and activities included both creative and disruptive/illegal activities while there were also questions regarding patterns of computer and Internet usage. The EPQ scale has been validated for use with Greek populations (Dimitriou, 1986). The 20-question Internet Addiction Test (IAT) (Young, 1996) has been administered to our research participants to ascertain any Internet abuse. Results are categorized into 3 categories according to the typical cutoff ranges of 20 to 49 (typical use), 50 to 69 (increased use), and more than 70 (addictive use). The questions on the IAT scale summarize typical criteria for Internet addiction. Item 1 refers to loss of sense of time; items 2, 6, and 8 refer to loss of function and productivity; items 13 and 20 to withdrawal effects; items 11 and 15 to rumination about Internet use; items 3, 5, 7, and 19 to prioritization over other needs while failed attempts to cut down on use are addressed with item 17. The questionnaire also includes questions on typical activities, which are connected to overuse, such as e-mailing and online relationships but not online gaming, which was not especially prevalent at the time it was created (1996). Hence an analysis of online activities was considered important and was included in the study design.
Descriptive Statistics and Bivariate Correlations
Table 1 presents basic demographics for our sample. Findings on substance use experience are comparable to nation-wide demographics for Greece (Hibell et al., 2009). Table 2 presents correlations between age, personality factors, IAT score, and number of substances tried during the last year. IAT score correlated positively with the psychoticism and neuroticism factors (P < 0.001) and negatively with the lie factor (P < 0.001). Another statistically significant correlation was detected between IAT score and the total number of illicit substances sampled during the last year (P < 0.001). IAT score correlated statistically significantly with time spent online, Spearman ρ = 0.573 (P < 0.001), while there was a statistically significant difference between those classified as addicted and those who were not as to time spent online as well, χ2 (6) = 151.648, P < 0.001.
Table 3 presents the mean values for age, personality factors, and IAT score for all responders to the questions on lifetime and recent substance use by gender. Comparisons made revealed significant differences both between and within the groups. Results indicated that male gender was a risk factor for both recent (P < 0.001) and lifetime (P = 0.006) substance use experience. Age was not linked to substance use experience although there was a notable but not statistically significant trend in lifetime experience in both sexes (P = 0.062 for boys and 0.077 for girls). Substance users presented with distinct personality profiles. Boys and girls who have used an illicit substance at any point in time tended to have higher values for psychoticism (Mann-Whitney Z = 7.818 for boys and 6.705 for girls, P < 0.001), neuroticism (Mann-Whitney Z = 3.786 for boys and 4.448 for girls, P < 0.001), and lower values in the lie scale (Mann-Whitney Z = 6.858 for boys and 3.963 for girls, P < 0.001). Similarly, boys and girls who recently used an illicit substance tended to have higher values for psychoticism (Mann-Whitney Z = 7.629 for boys and 5.781 for girls, P < 0.001), neuroticism (Mann-Whitney Z = 3.75 for boys and 3.386 for girls, P < 0.001). Boys also presented with lower values in the extraversion scale (Mann-Whitney Z = 2.163, P = .031) and lie scale (Mann-Whitney Z = 4.453, P < 0.001). In all cases, both boys and girls who have used an illicit substance, either in the past or recently, had higher values in the IAT test (P < 0.001).
Table 4 presents the mean values for age and EPQ factors by sex and Internet usage categories. Group comparisons employed the χ2, Mann-Whitney, and Kruskal-Wallis statistics. There were some notable findings when comparing those groups. Boys tended to be heavier Internet users than girls (P < 0.001). The age differences between and within the sexes were nonsignificant. The EPQ profiles differed significantly both between and within the sexes. Boys presented with higher psychoticism values (Z = 8.342, P < 0.001) and girls with higher neuroticism values (Z = 9.348, P < 0.001). As Internet use increased in severity, boys tended to have higher values in the psychoticism (Kruskal Wallis χ2 = 58.168, P < 0.001) and neuroticism (Kruskal Wallis χ2 = 48.407, P < 0.001) factors and lower values in the extraversion (Kruskal Wallis χ2 = 12.71, P = 0.002) and lie (Kruskal Wallis χ2 = 42.206, P < 0.001). Girls also had higher values for psychoticism (Kruskal Wallis χ2 = 54.226, P < 0.001), neuroticism (Kruskal Wallis χ2 = 19.056, P < 0.001), and lie factors (Kruskal Wallis χ2 = 19.543, P < 0.001) but not for extraversion (Kruskal Wallis χ2 = 3.530, P = 0.171).
Table 5 presents the online activities favored by adolescents who used at least one illicit substance during the last month compared with those who did not. Results were adjusted for multiple comparisons with the employment of the stringent Bonferroni correction. There were 3 answers that remained statistically significant after this correction. Adolescents who sought online pornography or declined to answer as to their surfing habits were more likely to have tried an illicit substance during the last month, while those who reported having used the Internet to search for study-related information were less likely.
Binary Logistic Regression Outcomes
In the results presented earlier, there were obvious parallels between illicit substance abuse on the one hand and Internet abuse on the other with regards to the psychological profiles as defined by the EPQ factors. This association between illicit substance use, gender, age, personality factors, and scores on the Internet Addiction Test was further examined using binary logistic regression. The test outcomes were illicit substance use experience anytime during the lifetime and illicit substance use during the last month, with a 2-step design where Internet addiction scores were entered in the last step and the other variables served as control variables. Results presented in Table 6 demonstrate that Internet addiction test scores are an important predictor for recent substance use (P < 0.001) and lifetime substance use experience (P < 0.001) when controlling for gender, age, ethnicity, and personality factors.
A student who used an illicit substance during the last month was older, identified himself as member of a separate ethnic group, and had higher psychoticism and Internet addiction scores (χ2 = 170.081, df = 12, P < 0.001). Gender, extraversion, neuroticism, and lie factor scores were not significantly associated with illicit substance use under this model. The benefit in model fit between the 2 steps was statistically significant (Δχ2 = 23.503, df = 1); thus, the inclusion of the IAT score in the model was justified. The 2-step model has an estimated Nagelkerke R2 equal to 0.452, indicating that 45.2% of the variance in whether a student took an illicit substance or not during the last month can be predicted from the linear combination of the variables in the model. Tolerance values for all variables were higher than 1 − r2 (54.8) indicating acceptable levels of collinearity. Results are similar for a student who had lifetime substance use experience and would typically be older with higher psychoticism and Internet addiction scores (χ2 = 185.19, df = 12, P < 0.001). Again, the inclusion of the IAT score in the model was justified (Δχ2 = 31.33, df = 1). The corresponding Nagelkerke R2 value was 0.346, indicating that 34.6% of the variance in whether a student had ever used an illicit substance can be predicted by the model.
Personality Correlates of Internet and Substance Abuse
Our study has replicated earlier findings on correlations between Internet abuse on the one hand and personality factors on the other (Cao and Su, 2007). Our findings suggest that the PEN personality profile of an Internet user presents distinct differences as the level of pathological use increases, from moderate to heavy and on to addictive use. Likewise, subjects with lifetime or recent experience of illicit substance use had different PEN personality profiles than those with no such experience.
Those postulates are in accordance with our findings. Our logistical regression model includes Eysenck's “psychoticism” factor as a significant risk factor for substance abuse but not the “neuroticism” or “lie” factors. This demonstrates that in our adolescent, general population sample, the psychoticism trait has primacy among the factors ascertained by the Eysenck personality model with regards to addiction. The fact that the score of the IAT test remains a statistically significant predictor after controlling for age, sex, ethnicity, and personality demonstrates that Internet addiction shares certain components with chemical addictions, which remain unaccounted for in our study, possibly of familial or wider social context. Since those factors are usually hard to determine while screening large populations, the inclusion of a simple self-report instrument that measures the degree of Internet abuse can be beneficial for early-catchment programs.
Seeking online pornography was the sole Internet activity that tended to be more frequent among adolescents who had a recent experience of illicit substance use. A related review presented research evidence regarding an association of drug-seeking behavior and novelty-seeking behaviors, including an interest in seeking and watching pornography (Bardo et al.,1996). In this review, the authors put forward the hypothesis that individual differences in response to novelty and drugs may relate to individual differences in the mesolimbic dopamine (DA) system of the brain, a hypothesis that appears to fit our aforementioned findings.
Seeking study-related information on the Internet tended to be less frequent among the same adolescents. Research has shown that the psychoticism trait has been associated with an aversion to school work (McCown and Johnson, 1991) and testing for differences in our sample replicated this finding, those users who did not use the Internet for study tended to have statistically significantly higher values for psychoticism than those who did (t = 6.089, df = 1015, P < 0.001).
Relationship Between Internet Abuse and Drug Abuse—Implications for Research, Prevention, and Clinical Practice
We detected increased levels of Internet abuse both among adolescents who had a recent experience of illicit substance use and among those adolescents who have had a similar experience anytime during their lifetime. A positive correlation was discovered between IAT scores and having used multiple illicit substances (polydrug use). Polydrug use among adolescents can be an indicator of early initiation, risk behaviors, or deviance. It can also be symptomatic of more established patterns of multiple substance use, potentially carrying long-term health problems and acute risk during leisure time. Those adolescents eager to try any illicit substance are a prime target for early intervention programs. Reaching out to adolescents who do not have established patterns of use can be problematic since they do not have a self-representation as a “user” nor can they be identified by the adverse effects of established drug use. Our findings show that there may be some merit in specifically targeting the young population, which tends to overindulge in Internet use, with drug prevention programs. Using an Internet-based prevention and treatment program may be the ideal way for a first contact with the services by specifically promoting it in typical venues where Internet overuse occurs (Byun et al., 2009; Douglas, Mills, Niang et al., 2008), namely online gaming sites, social networking sites, and programming and hacking communities. Furthermore, a cost analysis study should reveal whether promoting not only specific Web-based programs but general anti–drug use campaigns on those venues has additional merit compared with traditional dissemination.
There is also a serious comorbidity issue since there is no study regarding any adverse effect of concurrent pathological Internet use in drug abuse treatment. Although this problem may be temporarily relegated to a secondary role if the subject presents with chemical substance abuse, there is no relevant theoretical framework with regards to this novel “dual” addiction. A number of important questions arise such as whether having Internet addiction hampers the psychological effect of substance abuse treatment programs, or whether increased Internet use may be considered a behavioral “substitute” that may be promoted in cases where the subject cannot control an urge to relapse to a chemical substance. These issues are common with other addictive behaviors that do not include the use of chemical substances such as gambling (Winters and Anderson, 2000), kleptomania (Sarasalo et al., 1996), and other impulse-control disorders (McElroy et al., 1992). The Internet, however, has the unique quality of a medium that is not morally frowned upon or stigmatized in the community but rather promoted as a significant contributor to modern advances in all aspects of our technical civilization. One would expect that a substance abuser may not consider his pathological Internet use as a significant problem compared with his substance abuse difficulties and negate to report it, or consider it a harmless alternative to substance abuse. However, since Internet abuse has considerable negative impact on all aspects of sociability and general well-being, it may pose a risk for the long-term effectiveness of substance abuse treatment programs. There is, therefore, a need for future research examining the views and habits of substance abusers regarding pathological Internet use and the effect it may have on long-term abstinence from the substance. Furthermore, the inclusion of at least one valid self-report instrument regarding Internet addiction in the typical screening procedure of substance abuse treatment programs may be of substantial help with the planning of a personalized treatment regime.
A clear limitation of this study is the reliance on subjective reports on drug use since questionnaires can be affected by socially desirable responding or impression management. However, this method has been frequently employed in the task of gaining insight on the prevalence of drug use and it is widely accepted as a reasonable alternative to more rigorous and costly alternatives (Darke, 1998; Boca and Noll, 2000). Likewise, self-report questionnaires on the subject of Internet addiction may be affected by the same factors. Research on the field is generally hampered by the lack of a common set of diagnostic criteria or even a universally accepted definition. This problem may be addressed in the future editions of psychiatric nosological manuals as the Diagnostic and Statistical Manual of Mental Disorders (Miller and Holden, 2010). Our research demonstrates some commonalities with an established addiction paradigm, which could be of value in this wider discussion currently under way.
Adolescents who have used illicit substances and are abusing the Internet as well appear to share some common personality characteristics, namely those that are classified under the label of “psychoticism.” The possible existence of a common biological factor remains to be researched and this research could benefit from targeting the dopamine pathways of the brain.
We found that an increase in the severity of pathological Internet use can be linked to increased chances of having used an illicit substance. Since excessive Internet use can be readily observed in a home environment, it is of some interest whether it can be considered a predictive factor for ascertaining possible substance abuse. Our results indicate that while taking into account any common personality attributes, Internet addiction can still be useful as a predictor variable for substance use experiences.
Our results may have important implications for early catchment programs since Internet abusers may be more easily reached through the Internet itself; a dissemination of a drug prevention program to this specific population may be beneficial. The next steps in this field should include the experimental targeting of those special populations with specific campaigns and treatment programs while evaluating for cost effectiveness.
The authors thank the staff of the ‘Hippocrates' Center for Drug abuse prevention in carrying out this research project.
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adolescents; internet addiction; personality; substance use