Origins and Pathways to Drug Abuse

Research Findings from May, 2004 Director's Report

This section lists selected summaries from NIDA funded research projects that investigate the origins and pathways to drug abuse. The summaries provided were selected from recent issues of the Director's Report to the National Advisory Council on Drug Abuse. For a more comprehensive listing of NIDA funded projects see the Director's Report.

Malleability of Early Social and Environmental Enrichment Effects in the Rat

Early social and environmental enrichment experiences have been shown to have profound effects on subsequent responsivity and vulnerability to drugs of abuse in animals. For example, studies on opiates have shown that group-housed rats are more sensitive than isolates to both antinociceptive and reinforcing effects of opioid mu agonists such as morphine and heroin. Previous studies suggest that these effects may be due to differences in opiate receptor density, which is increased under conditions of group housing. The present study examined the effects of these environmental manipulations on sensitivity to kappa opioid agonists. Animals were obtained at weaning (21 days) and assigned to isolate (IC) or group housed (enriched or EC) conditions for seven weeks. EC rats were reared in an enriched environment with various objects for exploration and interaction. The EC group was subsequently found to be significantly more sensitive to analgesia produced by highly selective kappa agonists. When tested for conditioned place preference, all animals spent less time in the compartment previously paired with a kappa agonist (as has previously been reported), but enriched rats were more sensitive to this effect. At week fourteen, the investigators reversed housing conditions in these two groups - isolates were switched to group housing with enrichment and group housed rats were switched to isolated housing. Seven weeks later tail-flick analgesia was re-determined and a reversal of the housing condition influence was observed. Hence, the kappa agonist produced less analgesia in previously EC animals switched to IC, and more analgesia in IC rats now living under EC conditions. While additional behavioral investigations need to be conducted to determine if this observation generalizes to direct measures of drug reinforcement and reward, it suggests that the effects of early, deleterious environmental conditions may be overcome by subsequent environmental stimulation. Smith, M.A., Bryant, P.S. and McClean, J.M. Social and Environmental Enrichment Enhances Sensitivity to the Effects of Kappa Opioids: Studies on Antinociception, Diuresis and Conditioned Place Preference. Pharmacol Biochem Behav, 76, pp. 93-101, 2003.

Early Environmental Enrichment Alters Nicotine's Behavioral Activating Effects

There are suggestions from the literature that adolescent animals may be more sensitive to both the behavioral stimulatory effects of nicotine, and to its reinforcing properties. Thus, it is important to investigate how environmental factors affect these differential sensitivities. Many previous investigations with animals have revealed that environmental enrichment (EC) conditions affect subsequent response to drugs of abuse. For example, EC rats are more sensitive to the acute behavioral and neurochemical effects of amphetamine than those raised in an impoverished (IC) environment. EC rats also exhibit less locomotor sensitization to repeated amphetamine treatment, probably due to this greater initial sensitivity. In the laboratory of Dr. Michael Bardo, investigators have been studying how early environmental conditions influence the behavioral effects of psychostimulants. In the present study, 21-day-old rats were assigned to EC, IC or a social (SC) enrichment condition. SC rats were group housed, and EC animals also had the additional stimulation of objects to explore in their environment. In two separate assessments, conducted at 51 days of age, animals were tested for locomotor effects of s.c. 0.2 or 0.8 mg/kg of nicotine, compared to a saline control injection. Eight drug challenges were performed -- one every 48 hours. On the ninth session, rats were tested for sensitization with 0.8 mg/kg nicotine. In Experiment 1, data from IC and EC rats were examined from the first and the last drug treatment (session 1 and 8). EC rats exhibited significantly less nicotine-induced locomotor change over the 60 min post injection than did IC animals. This was true of both early session hypoactivity, and later session hyperactivity produced by 0.2 mg/kg. On the high dose test for sensitization, EC rats again showed less locomotor effects from the nicotine injection. In Experiment 2, EC and SC groups were examined with only 0.2 mg/kg nicotine over a similar eight sessions. Neither group showed locomotor effects after nicotine on session one and there were few changes from saline controls on session 8. On a day nine challenge with 0.8 mg/kg, only SC rats exhibited nicotine hyperactivity, suggesting that EC blocked the development of behavioral sensitization. Overall, these observations suggest that early environmental enrichment induces a neurobiological substrate change that subsequently renders an animal less sensitive to nicotine's behavioral stimulation. Additional studies are needed to determine the effect of EC on the reinforcing properties of nicotine. Green, T.A., Cain, M.E., Thompson, M. and Bardo, M.T. Environmental Enrichment Decreases Nicotine-induced Hyperactivity in Rats. Psychopharmacol, 170, pp. 235-241, 2003.

Adolescent Sensitivity to Nicotine and Cross-sensitization to Cocaine Effects in Adulthood

In 2002, Dr. Sari Izenwasser reported that peri-adolescent rats were less sensitive to the development of behavioral sensitization with repeated cocaine administration than their adult counterparts. This was an important observation, as sensitization is believed to reflect an underlying change in the neurobiological substrate for reinforcing effects of drugs of abuse, and therefore may be involved in the addiction process. More recently, she has examined the behavioral and neurochemical effects of repeated nicotine treatments in this model. The study of nicotine mechanisms in adolescence is also an important area of investigation, since it has been reported that adolescents show a more rapid progression to dependence on smoking than do adults. Moreover, girls may show an even more precipitous course. In this study, adult and peri-adolescent rats (postnatal day 28 to 40) received 0.4mg/kg of nicotine/day via intra-peritoneal administration for 7 days. Matched age and sex control groups received vehicle instead. After each injection, locomotor activity was measured for one hour. On day 8, all rats were challenged with a cumulative dosing regimen of i.p. cocaine and their locomotor activity tested for 10-min after each injection to probe for cross-sensitization. This portion of the study design addresses concerns that smoking or nicotine exposure may "prime" subsequent illicit drug abuse. Both developmental and gender differences were observed in acute effects of nicotine and in the development of sensitization to locomotor stimulation: The young male group had a higher activity count (and greater stereotypy) after the first nicotine injection than all other groups, and did not show a behavioral sensitization. All other groups (female adolescent, and both adult groups) sensitized to nicotine's behavioral activating and stereotypy effects. However, female adolescents showed a significant sensitized response after only one nicotine exposure (versus adults, who showed significant sensitization on day five for both behavioral measures). Unlike their response on locomotor measures, male adolescents did show a sensitized stereotypy that emerged on the fourth nicotine injection. When all groups were challenged with cocaine on day 8, adolescent males - who had not shown locomotor sensitization to repeated nicotine - were sensitized to all doses of cocaine tested (i.e., had higher activity counts than males treated with vehicle) and, in fact, showed greater cross-sensitization than their adult counterparts. By contrast, neither female group showed any greater response than their chronic vehicle controls after cocaine. These findings, in conjunction with previous reports of gender differences in rats treated acutely, or chronically, with behaviorally active doses of nicotine, highlight potential neurobiological differences in the substrates for addictive processes in adolescence. Thus, although methodological differences between these various studies must be considered (e.g., varied routes of administration and schedules), male adolescents may be initially more behaviorally responsive to nicotine, whereas females may show a more rapid neuroadaptation that gives rise to changing behavioral profiles. Collins, S.L. and Izenwasser, S. Chronic Nicotine Differentially Alters Cocaine-induced Locomotor Activity in Adolescent vs. Adult Male and Female Rats. Neuropharmacology, Available online December 10, 2003.

Genetic and Environmental Influences on Substance Initiation, Use, and Problem Use in Adolescents

Dr. Thomas Crowley and colleagues at the University of Colorado conducted a sibling/twin/adoption study of substance initiation, use, and problem use, estimating the relative contribution of genetic and environmental influences on these phenotypes in adolescents. The participants were 345 monozygotic twin pairs, 337 dizygotic twin pairs, 306 biological sibling pairs, and 74 adoptive sibling pairs. Results showed that there were moderate to substantial genetic influences, with the exception of alcohol use and any drug use, and modest to moderate shared environmental influences on substance initiation, use, and problem use. For alcohol and any drug, heritability was higher and the magnitude of shared environmental influences was lower for problem use than for initiation or use. Environmental influences shared only by twin pairs had a significant effect on tobacco initiation, alcohol use, and any drug use. For tobacco use, tobacco problem use, and marijuana initiation, heritability was higher and the magnitude of shared environmental influences was lower in female than in male adolescents. There was no evidence for sex-specific genetic or shared environmental influences on any variable. The moderate to substantial heritabilities found for adolescents in the present study are comparable to those found in twin studies of adult substance use and substance use disorders. The finding that problem use is more heritable than initiation and use is also consistent with the results of adult twin studies. The significance of environmental influences shared only by twin pairs on tobacco initiation, alcohol use, and any drug use suggests the influences of peers, accessibility of substances, and sibling interaction. Soo Hyun Rhee, S.H, Hewitt, J.K, Young, S.E., Corley, R.P., Crowley, T.J. and Stallings, M.C. Archives of General Psychiatry, 60, pp. 1256-1264, 2003.

Event-Related Functional Magnetic Resonance Imaging of Reward-Related Brain Circuitry in Children and Adolescents

Dr. Julie Fiez and colleagues at the University of Pittsburgh used functional magnetic resonance imaging to investigate the brain reward systems of normal children and adolescents. Regions and time-courses of reward-related activity were similar to those observed in adults with condition-dependent BOLD changes in the ventral striatum and lateral and medial orbital-frontal cortex. Reward-related activity in these regions exhibited larger responses to positive than to negative feedback. These results provide further a baseline from which to understand the pathophysiology of reward-related disorders, such as substance abuse, in youth. May, J.C., Delgado, M.R., Dahl, R.E., Stenger, V.A., Ryan, N.D., Fiez, J.A. and Carter, C.S., Biological Psychiatry, 55(4), pp. 359-366, 2004.

Neurobehavior Disinhibition in Childhood Predicts Substance Use Disorder in Young Adulthood

The development of substance use disorder (SUD) was prospectively investigated in 66 boys having fathers with SUD and 104 boys having fathers with no adult psychiatric disorder. Evaluations were conducted to determine the context in which neurobehavior disinhibition in relation to parental SUD, parental neglect of the child and child's social maladjustment culminated in a DSM-III-R diagnosis of SUD. A neurobehavior disinhibition latent trait reflecting prefrontal cortex disturbance was derived using indicators of behavior undercontrol, affect dysregulation and executive cognitive functioning in the boys when they were 10-12 and again at 16 years of age. The data were analyzed to determine whether the score on the neurobehavior disinhibition construct mediates the association between father's and mother's SUD and son's SUD. Several key results emerged. First, SUD in the mother and father predicted neurobehavior disinhibition in the son. Second, the neurobehavior disinhibition score of the sons at ages 10-12 predicted SUD at age 19. Third, neurobehavior disinhibition, in conjunction with social maladjustment and drug use frequency, mediated the association between paternal and maternal SUD and son's SUD. Fourth, neurobehavior disinhibition was unrelated to neglect of the child by either the father or mother; however, paternal but not maternal neglect at age 10-12 predicted SUD at age 19. These findings suggest that prefrontal cortex dysfunction contributes to SUD liability. Tarter R.E., Kirisci L., Habeych M., Reynolds M. and Vanyukov M. Neurobehavior Disinhibition in Childhood Predisposes Boys to Substance Use Disorder by Young Adulthood: Direct and Mediated Etiologic Pathways. Drug and Alcohol Dependence, 73, pp. 121-132, 2004.

Family Transmission of Marijuana Use, Abuse, and Dependence

This is the first family study to specifically examine the familial aggregation of marijuana use, abuse, and dependence. Subjects included adolescents recruited from residential and day treatment programs for youths with conduct and substance problems, matched controls, and all available family members. A total of 2,546 individuals from 781 families were interviewed with structured research instruments. Risk ratios of relatives of clinical cases were calculated compared with controls, for marijuana use, abuse, or dependence. Spousal, parent-offspring, and sibling correlations and the proportion of variance attributable to parent-offspring transmission were estimated using structural equation modeling. The results indicated that, for all three measures, the risk ratios were elevated in the family members of clinical probands, with estimates ranging from 1.5 to 3.3. Spousal correlations ranged from 0.33 to 0.70. Parent-offspring correlations ranged from 0.17 to 0.30. Sibling correlations ranged from 0.34 to 0.44. The proportion of variance attributable to factors transmitted from parents to children ranged between 25% and 44%. Results demonstrate significant parent-offspring transmission of risk, sibling environmental influences, and assortative mating for all three levels of marijuana use. Hopfer C.J., Stallings M.C., Hewitt J.K., and Crowley T.J. Family Transmission of Marijuana Use, Abuse, and Dependence. Journal of the American Academy of Child and Adolescent Psychiatry, 42, pp. 834-834, 2003.

Common Predictors of Cigarette Smoking, Alcohol Use, Aggression, and Delinquency Among Inner-City Minority Youth

The present study examined the prevalence rates and common predictors of substance use, aggression, and delinquency among inner-city minority youth entering middle school. A survey was administered to 6th grade students (N = 5423) from 42 New York City schools. Aggressive behaviors were reported most frequently, followed by delinquent behaviors, alcohol use, and cigarette smoking. Across all behavioral outcomes, social and environmental influences explained the largest proportion of variance, followed by individual characteristics and skills, bonding to conventional institutions, and demographic variables. For the majority of predictor variables there was substantial overlap in patterns of prediction across outcomes. These findings indicate that several factors that correspond to the predominant psychosocial theories of adolescent development explain variation across different problem behavior outcomes among inner-city minority youth. Griffin, K.W., Botvin, G.J., Scheier, L.M., Doyle, M.M., and Williams, C., Common Predictors of Cigarette Smoking, Alcohol Use, Aggression, and Delinquency Among Inner-City Minority Youth. Addictive Behaviors, 28, pp. 1141-1148, 2003.

The Deterrence Hypothesis Reexamined: Sports Participation and Substance Use Among Young Adults

The widely held notion that sports participation reduces subsequent risk of substance use is evaluated with longitudinal survey data of a representative sample of 1,172 youth when they were in their preteen and young adult years. Unlike previous inquiries into the deterrence hypothesis, the present study controls for other major factors previously found to be predictive of alcohol and drug use, such as family structure and stress exposure. Results of analyses revealed that contrary to the deterrence hypothesis, playing high school sports does not appear to be a protective factor that lowers one's involvement in young adult alcohol or drug use--with one exception. Subgroup analyses revealed that among blacks, the greater the extent of high school sports participation the less the risk of substance use. In direct contradiction to the deterrence hypothesis, playing high school sports was found to be positively associated with alcohol use for whites, even in the context of other major predictors of alcohol use. Further analyses revealed that the positive association between sports participation and alcohol use appeared to exist only for white males. These findings cast doubt about the contention that playing high school sports is protective against alcohol and illegal substance use. Eitle, D., Turner, R.J. and Eitle, T.M. The Deterrence Hypothesis Reexamined: Sports Participation and Substance Use Among Young Adults. Journal of Drug Issues, 33, pp. 193-222, 2003.

Substance Use References in the Lyrics of Favorite Songs of African-American Adolescents

Concerns have been raised regarding the effect of media messages on health risk behaviors, particularly given that media with explicit content are often marketed toward adolescents under the age of 18 (Federal Trade Commission 2000). The goal of this study was to investigate the extent to which drug-related references were present in popular songs nominated by a sample of African-American adolescents. To address this issue, secondary data analyses were performed using data originally collected by the Reaching Adolescents, Parents, and Peers project (Project RAPP). In the spring of 1997, participants reported their five favorite songs. Songs that were nominated five or more times by the sample (popular songs) were coded for genre and drug-related content. Of the 93 popular songs, the most popular genres were R&B (34%), gangsta rap (32%), and non-gangsta rap (27%). The majority of rap (68%) and gangsta rap (80%) songs contained at least one reference to illicit drugs, whereas few R & B songs did (6%). Marijuana and stimulants were the most commonly referred to drugs. These findings substantiate the need for more research on the potential relationship between exposure to media messages and drug use among adolescents. Brookshire, C.D., Stevens, E., Bryant, S., Browne, D.C., and Clubb, P. Substance Use References in the Lyrics of Favorite Songs of African-American Adolescents. Journal of Young Investigators, 1(1), pp 1-7, 2003.

Childhood Compelled Sex and Its Relationship to Structural Disadvantage, Subcultural Norms, Violence, and Illicit Drug Use in Inner City Households

There are a number of studies that have linked child sexual abuse to various adverse outcomes, including substance abuse. This study is a retrospective, qualitative study that seeks to understand the etiology, significance, and response to early compelled sex within the social context of poor, inner-city, predominantly African-American households (approximately 72 households) in New York City. Adult sexual contact with girls was widespread, even the norm in many impoverished households, although it is not accepted behavior by everyone living in the inner city. 61% of female subjects reported having compelled sex by age 13. Typically this activity took place regularly over time and fit within the young girl's sexual development pathway leading to independent sexuality. Many adults do not regard compelled sex as a major problem, and compelled sex is consistent with other subcultural behaviors, including violence and the ever-present threat of violence. The primacy of drug use in the lives of many inner-city residents also supports the acceptance of these subcultural norms and the commodification of sexual behavior (exchange of sex for food, rent money, drugs). Dunlap, E., Golub, A. and Johnson, B. Girls' Sexual Development in the Inner City: From Compelled Childhood Sexual Contact to Sex-for-Things Exchanges. Journal of Child Sexual Abuse, 12(2), pp. 73-96, 2003.

Substance Use Disorders Related to Attempted Suicide in Adolescents

This study examined the effects of psychiatric disorders on attempted suicide among adolescents with substance use disorders (SUD). Age of onset for psychiatric disorders, age of first suicide attempt, and the relationship of psychiatric disorder with attempted suicide were investigated in a sample of 503 adolescents with DSM-IV defined SUD (age range: 12.2-19.0 years). Results indicated that males who attempted suicide had a significantly earlier onset of alcohol use disorders (AUD) and significantly more mood, AUD, and disruptive behavior disorder symptoms compared to non-attempting males. Females who attempted suicide had a significantly earlier onset and higher counts of mood disorders and SUD symptoms compared to non-attempting females. Hazard analysis revealed that mood disorders represent the highest psychiatric risk for attempted suicide in both the genders. Attention deficit-hyperactivity disorder (ADHD) increased the risk for attempted suicide among males. The interaction of mood disorder and AUD increased the risk for attempted suicide among females. The investigators conclude that clinicians should closely monitor SUD adolescents for suicide risk and be aware of gender differences for suicidal behavior based on course and severity of psychiatric disorder in this population. Kelly, T.M., Cornelius, J.R. and Clark, D.B. Psychiatric Disorders and Attempted Suicide Among Adolescents with Substance Use Disorders. Drug And Alcohol Dependence, 73(1), pp. 87-97, 2004.

Review of Twin and Adoption Studies of Adolescent Substance Use

This paper reviews studies of adolescent substance use and abuse with twin and adoption studies. Results were presented by design, sample, and stage of drug use. Of 19 studies that used adolescent samples, 18 examined initiation or use of substances and 1 examined abuse. Of the 7 retrospective studies using adult samples, 6 examined problematic behaviors such as substance dependence. Genetic and shared environmental influences on adolescent substance use appear to be moderated by the specific substance, age, gender, specific contexts, religiousness, and region. There is some evidence for a common genetic influence on substance use across substances. Genetic influences on adolescent substance use may act through an influence on disinhibited behavior. Shared environment contributed to adolescent substance use consistently across all adolescent samples and common shared environmental factors influenced initiation into tobacco and alcohol use. While parental alcohol use had a small influence on adolescent shared environment, sibling influences were substantial. In summary, twin and adoption studies have increased our understanding of genetic and environmental influences on adolescent substance use and its initiation, although more studies focusing on clinical syndromes of abuse and dependence are needed. Hopfer, C.J., Crowley, T.J., and Hewitt, J.K. Review of Twin and Adoption Studies of Adolescent Substance Use. Journal of the American Academy of Child and Adolescent Psychiatry, 42, pp. 710-719, 2003.

Sensation Seeking is a Moderator of Peer Effects and Perceived Peer Marijuana Use on Cigarette and Marijuana Use

This study tested the concurrent effects of peer influence and protective cognitive variables on marijuana and cigarette use to determine if they are contingent on adolescent sensation seeking. It tested two hypotheses: (1) low sensation-seekers would be more likely to resist pressures from risk-taking peers than their high-sensation-seeking counterparts and (2) low sensation seekers are more likely to be deterred from cigarette and marijuana use by the perceived negative consequences of harm than high sensation-seekers. Data are based on survey responses of 3127 eighth graders from 10 small towns and rural communities. Findings indicate that sensation seeking is a risk factor for drug use among high but not low sensation seekers; however, sensation seeking does not become a risk factor in the absence of social pressures to use substances. Aspirations inconsistent with marijuana use appeared protective for high sensation seekers. Since low sensation seekers appear to be at relatively low risk even in the presence of peer risk factors or the absence of cognitive factors, the primary audience for substance use prevention efforts should be the sensation-seeking young adolescents and should seek to channel this group into alternative arousing and risk taking activities with nonsubstance-using peers. Slater, M.D. Sensation-Seeking as a Moderator of the Effects of Peer Influences, Consistency with Personal Aspirations, and Perceived Harm on Marijuana and Cigarette Use among Younger Adolescents. Substance Use and Misuse 38, pp. 865-880, 2003.

Familism, Parental Monitoring & Knowledge as Predictors of Adolescent Drug Use

The authors investigated relationships between marijuana and inhalant use and measures of familism, parental monitoring, drug use knowledge and acculturation as well as demographic factors in 1,094 Anglo and Hispanic youth from 5 school districts in southwest Arizona. Outcome measures addressed lifetime and 30-day marijuana and inhalant use. Hispanics exhibited higher use across all measures. Among Hispanic youth, high acculturation was associated with low marijuana but high inhalant use. In both Hispanics and Anglos positive family relations and parental monitoring were strongly associated with reduced marijuana use but only among youth most knowledgeable about drugs. Familism and monitoring were not associated with diminished use among the less knowledgeable. For inhalants, monitoring combined with high knowledge or with high familism was associated with attenuated use. The role of knowledge in reducing drug use suggests continuing to disseminate factual material. Prevention strategies also should incorporate a family component to inform parents and open lines of communication. Ramirez, J.R., Crano, W.D., Quist, R. Burgoon, M., Alvaro, E.M. and Grandpre, J. Acculturation, Familism, Parental Monitoring, and Knowledge as Predictors of Marijuana and Inhalant Use in Adolescents. Psychology of Addictive Behaviors. 18(1), pp. 3-11, March 2004.

Maternal Influences on Urban Adolescent Girls' Smoking Intentions

Prior research has shown that parents who smoke are more likely to have children who smoke. Moreover, adolescents have been found to overestimate the number of adults and teenagers who smoke. This overestimation produces an expectation of smoking as normative and has been associated with an increase use of cigarettes among adolescents. This study examined maternal social influences on cigarette usage among urban minority girls with interview data from 450 mother-daughter dyads recruited from 30 New York City public and parochial middle schools. Girls in this sample ranged in age from 11 to 15 years and reported smoking rates of about 18% and smoking intention rates of 24%. Most of the sample was either Black or Latina, with smaller percentages of other groups (White, Native American, Asian). Neither mothers' reports of their own smoking nor maternal attitudes toward children's smoking were predictive of girls' experimental smoking and intentions to smoke in the next year. However, girls who perceived their mothers to be smokers were more likely to have tried smoking and to say that they intend to try smoking compared to girls who perceived their mothers to be nonsmokers. Compared to girls with low normative expectations of adult smoking, girls with high normative expectations were 2.89 times more likely to have tried cigarettes and 2.32 times more likely to intend to smoke. These findings suggest that preventive interventions aimed at correcting normative expectations of smoking among parents and youth may be helpful in deterring smoking among children. Nichols, T.R., Graber, J.A., Brooks-Gunn, J., and Botvin, G.J. Maternal Influences on Smoking Initiation Among Urban Adolescent Girls. Journal of Research on Adolescence, 14, pp. 73-97, 2004.

Brief Measures of Sensation Seeking for Screening and Large-Scale Surveys

Sensation seeking is central to research on the prevention of risky health behaviors, but most measures of sensation seeking are fairly long. To increase the chances of inclusion of sensation seeking in research projects, the authors developed and evaluated two brief indices of sensation seeking, a four-item measure that retains the framework of the Sensation Seeking Scale-Form V (which is an 8-item measure), and a two-item measure focused on the risk-taking elements of sensation seeking. The performance of these new indices was compared with that of two well-documented longer measures of sensation seeking, based on data provided by more than 5,000 youth in grades seven through eleven. Psychometric analyses indicated that the internal consistency of the two new measures was very good overall and across grade and sex categories. Additionally, the new indices correlated with a series of risk and protective factors as well as tobacco, alcohol, and marijuana use. Since both indices performed in ways remarkably similar to the established measures of sensation seeking, they should prove useful for future research involving risky health behaviors. Stephenson, M.T., Hoyle, R.H., Palmgreen, P., Slater, M.D. Brief Measures of Sensation Seeking for Screening and Large-Scale Surveys Drug and Alcohol Dependence, 72, pp. 279-286, 2003.