Evidence for Deficits in Reward Responsivity in Antisocial YouthWith Callous-Unemotional TraitsVictoria A. Marini and Timothy R. Stickle

University of Vermont

This study investigated reward responsivity in youth with high levels of callous-unemotional (CU) traits using a cross-sectional design. Whereas deficits in respondingto punishment cues are well established in youth with CU traits, it is unclear whetherresponsivity to rewarding stimuli is impaired as well. Participants were 148 predomi-nantly Caucasian, adjudicated adolescents between the ages of 11 and 17 (M � 15.1,SD � 1.4) who completed the Balloon Analogue Risk Task as part of a larger batteryinvestigating aggression and social information processing. A Reward Responsivityvariable was created to capture changes in participants’ responding after receiving areward. A hierarchical regression analysis indicated that higher levels of CU traitssignificantly predicted less reward responsivity, above and beyond gender, sensationseeking, and impulsivity. Results support Blair’s (2004) Integrated Emotion Systemsmodel that proposes individuals with CU traits are impaired in their responsivity to bothappetitive and aversive stimuli.

Keywords: callous-unemotional traits, reward responsivity, aggression, youth, Balloon AnalogueRisk Task

Evidence for Deficits in Reward Processingin Antisocial Youth with Callous-

Unemotional Traits

Recent empirical work has extended the two-factor model of psychopathy from adult popu-lations to youth in clinical, community, andforensic samples (e.g., Christian, Frick, Hill,Tyler, & Frazer, 1997; Kruh, Frick, & Clem-ents, 2005; Salekin, Rosenbaum, & Lee, 2008).Two correlated dimensions have been identifiedthat comprise the construct of psychopathy: im-pulsivity (IMP) and callous-unemotional (CU)traits. The latter, in conjunction with conductproblems, predicts a pattern of severe andchronic antisocial behavior (ASB) among youth

(e.g., Barry, Barry, Deming, & Lochman, 2008;Burke, Loeber, & Lahey, 2007; Frick, Stickle,Dandreaux, Farrell, & Kimonis, 2005). Giventhe documented risks conferred by elevated lev-els of CU traits, it is critical to better understandthe specific role of CU traits in youth develop-ment.

To date, there is considerable evidence dem-onstrating reduced responsivity to affectivestimuli in youth high in CU traits (e.g., Blair,Colledge, Murray, & Mitchell, 2001; Loney,Frick, Clements, Ellis, & Kerlin, 2003), andthere is reason to believe this reduced emotionalresponsivity is an underlying mechanism in spe-cific developmental trajectories to ASB. Re-search on normal conscience development sug-gests that emotional arousability and discomfortin response to punishment are essential compo-nents of conscience development and the result-ing moral socialization (e.g., Burton, Maccoby,& Allinsmith, 1961; Kochanska, 1993). Thus,within this framework, reduced emotional re-sponsivity likely interferes with conscience de-velopment and, particularly when coupled withimpulsivity, places an individual at increasedrisk for ASB.

Given this putative mechanism, much of theextant research on antisocial individuals withCU traits has focused on responsivity to pun-ishment and threat cues, and has consistently

Victoria A. Marini and Timothy R. Stickle, Departmentof Psychology, University of Vermont.

This research was funded in part by a grant from Childand Adolescent Psychology Training and Research Foun-dation and by financial support from University of VermontDean’s Faculty Fund awarded to the second author.

The authors thank Judith Christensen and detention cen-ter staff and teachers for their generous support and theirtime, and Mark Bouton, Michael Zvolensky, and Carl Le-juez for helpful comments on earlier drafts of this article.

Correspondence concerning this article should be ad-dressed to Timothy R. Stickle, John Dewey Hall, Universityof Vermont, 2 Colchester Avenue, Burlington, VT 05405-1764. E-mail: tstickle@uvm.edu

Personality Disorders: Theory, Research, and Treatment © 2010 American Psychological Association2010, Vol. 1, No. 4, 218–229 1949-2715/10/$12.00 DOI: 10.1037/a0017675

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demonstrated underresponsiveness to thesecues. However, there is also evidence indicatingthat responsivity to positive and negative stim-uli is controlled by the same neural systems,particularly the amygdala and related structures(Baxter & Murray, 2002). Given emergent sup-port for amygdala dysfunction in psychopathicadults (Patrick, 1994) and for reduced amygdalaresponsiveness to emotional stimuli in youthhigh in CU traits (Marsh et al., 2008), it istheoretically plausible that individuals with CUtraits are underresponsive to both positive andnegative emotional stimuli. However, there is anotable gap in understanding the role of CUtraits in responsivity to positively valencedcues.

Before reviewing literature on emotionalresponsivity in individuals with CU traits, itis necessary to define emotion and how theconstruct relates to motivational systems thatdetermine behavior. Emotions are generallycharacterized as occurring within two opposingmotivational systems (Izard, 1992; Lang, 1995).Approach motivation is the propensity to focusbehavior toward positive stimuli (e.g., rewards).Conversely, avoidance motivation is the pro-pensity to focus behavior away from negative orunfavorable stimuli (e.g., punishment; Jones &Gosling, 2008). Because emotions are driven bythese two motivational systems, deficits in emo-tional responsivity could, in part, reflect a defi-ciency in one or both of these systems.

Deficits in the avoidance motivational systemare central to the conceptualization of psychop-athy and have been well-documented empiri-cally. Using a unitary construct of psychopathy(i.e., total scores on psychopathy measures in-cluding CU traits and impulsivity/recklessness)and various avoidance behavior methodology,research has shown that the avoidance system inindividuals with psychopathic traits is less re-sponsive to a variety of negative stimuli (Blair,1999; Blair, Jones, Clark, & Smith, 1997; Flor,Birbaumer, Hermann, Ziegler, & Patrick, 2002;Lykken, 1957; Newman & Kosson, 1986; New-man, Patterson, & Kosson, 1987).

However, a recently emerging conceptualiza-tion, Blair’s (2004, 2006) Integrated EmotionSystems (IES) model, suggests that individualswith high levels of CU traits, in particular,should be deficient in processing both positiveand negative stimuli (leading to deficits in ap-proach and avoidance motivation, respectively).

Despite emerging evidence supporting thismodel, few studies have examined basic ap-proach motivation, perhaps because most inves-tigations of reward and approach have used theresponse modulation paradigm. This paradigmhas been used to test Newman and colleagues’(e.g., Gorenstein & Newman, 1980; Newman,Patterson, Howland, & Nichols, 1990) responsemodulation hypothesis, which states that indi-viduals with psychopathic traits in general havedifficulty accommodating the meaning of con-textual environmental cues when engaged in agoal-directed activity. Consistent with this hy-pothesis, this methodological approach has pro-vided much empirical support for a reward-dominant response style (e.g., Fowles, 1988;O’Brien & Frick, 1996), which is demonstratedby difficulty in responding to the changing val-ues of reinforcements. Consequently, it hasbeen suggested that individuals with psycho-pathic traits are overresponsive to rewards.However, we argue that this framework pro-vides support for difficulties with regulating theapproach motivational system, yet does not ad-dress basic responsivity of the approach system.

Of the few studies that have investigated re-sponsivity of the approach system, several haveshown support for an underresponsive approachsystem (Blair, Peschardt, Budhani, Mitchell, &Pine, 2006; Mitchell, Richell, Leonard, & Blair,2006; Rubia et al., 2009; Verona, Patrick, Cur-tin, Bradley, & Lang, 2004); yet at least onestudy did not find a relation between total psy-chopathy scores and activation of the approachsystem (Kimonis, Frick, Fazekas, & Loney,2006). These limited, yet conflicting results re-garding whether and to what degree individualshigh in CU traits display deficits in their ap-proach system underscore a need to investigatefurther the relations among approach and avoid-ance motivation and CU traits.

Specifically, there are several limitations withthe existing research on CU traits, emotionalresponsivity, and motivational systems. First,except for Verona and colleagues (2004), theabove studies used total psychopathy scores intheir analyses, rather than CU (Factor 1) andIMP (Factor 2) domains separately. This ap-proach lends ambiguity to whether impairmentsare related to CU traits (affective domain) or toimpulsivity and/or attentional difficulties (cog-nitive domain). Because CU traits are concep-tually linked to emotional dysfunction, a unique

219REWARD RESPONSIVITY AND CU TRAITS

empirical relation would clarify whether deficitsin the approach and/or avoidance motivationalsystems are associated with this factor. Addi-tionally, most investigations of the approachsystem and psychopathy have been conductedwith adults (e.g., Newman & Kosson, 1986;Newman et al., 1990), with the exception ofO’Brien & colleagues’ (1994; 1996) with ado-lescents, thus lending ambiguity to the develop-mental timing of this vulnerability.

Furthermore, from a methodological stand-point, investigations of the approach systemhave utilized paradigms that typically includerewards and punishments of equal strength. Atask that has does not prime either motivationalsystem, yet pairs a strong reward contingencywith weak punishment may facilitate under-standing of the responsivity of the approachsystem independently from the avoidance sys-tem. A task with an asymmetry in the strengthof punishments and rewards has not yet beenutilized with youth.

Taken together, it remains unclear whether theapproach system in youth with high levels of CUtraits is overresponsive, underresponsive, or ap-propriately responsive. Understanding how youthhigh in CU traits respond to environmental cueshas implications for tailoring interventions,which is especially important given evidence ofthese youths’ poor response to treatment(Hawes & Dadds, 2005, 2007). Accordingly,we examined responsiveness of the approachsystem in a sample of adjudicated adolescents.Because this type of sample is most likely tohave sufficient numbers of youth with high lev-els of CU traits and these individuals have ahistory of delinquent behavior, this sample waswell-suited to investigate the approach systemand its relation to behavioral decision-making.The current study used the adolescent version ofthe Balloon Analogue Risk Task (BART-Y;Lejuez et al., 2007) to measure activation of theapproach system. The BART-Y is typicallyconceptualized as an experimental task that re-flects real-life reward-seeking behavior, whichconceptually should activate the approach sys-tem. This task was selected because (1) thepunishments are relatively weak compared tothe rewards (thus introducing asymmetry; dis-cussed in detail in the Method section), and (2)the punishment occurs according to a predeter-mined sequence so the participant cannot learnwhen to avoid it (thus a reward-dominant re-

sponse set is not established). The latter wasconsidered especially important because thecurrent study sought to investigate motivationalresponsivity rather than regulation.

Our primary hypothesis is that CU traits willexplain unique variance in approach motivation(operationalized as the pursuit of reward) aboveand beyond IMP and sensation seeking. IMPand sensation seeking were included becausethey have demonstrated relations to theBART-Y (Lejuez et al., 2007). To test the gen-eral emotional dysfunction hypothesis in indi-viduals with CU traits, we hypothesized thathigher levels of CU traits would predict signif-icantly less responsivity to reward, thereby sug-gesting that youth with high levels of CU traitshave an underresponsive approach motivationalsystem. Furthermore, because the BART-Y, asscored in these analyses, is hypothesized to be ameasure of simple reward responsivity with amild punishment, punishment responsivity wasexpected to be unrelated to CU traits.

Method

Participants

One hundred forty eight adolescents betweenthe ages of 11 and 17 (M � 15.1, SD � 1.4)were selected from a study investigating aggres-sion and social information processing in adju-dicated youth. The original sample consisted of150 adolescents; however due to a programmalfunction within the BART-Y, individualtrial data needed to compute the reward respon-sivity variable was lost on two participants. Theentire sample was recruited from two juveniledetention centers within the same state. Femaleswere oversampled by recruiting participantsfrom one all-female and one coed facility. Fe-males compose 41% of the present sample, ex-ceeding the detention population of approxi-mately 30% females. The present sample is14% ethnic minority, with approximately 2%African American, 7% Hispanic, and 5% fromother minority groups, which exceeds the statepopulation of approximately 5% minority. Ex-clusion criteria included (1) intellectual impair-ment that would limit ability to validly com-plete measures, as determined by a score lessthan or equal to 80 on the basic reading subtestof the Wide Range Achievement Test(WRAT-3; Wilkinson, 1993) and inadequate

220 MARINI AND STICKLE

academic functioning; (2) otherwise limitedmental competency, including any of the fol-lowing conditions: pervasive developmentaldisorders, mental retardation, selective mutism,organic mental disorders, schizophrenia, orother psychotic disorders; (3) the inability togive informed, written assent; and (4) residingat the detention center for less than 2 weeks toensure completion of the protocol. A total of 15youth were excluded for the following reasons:limited intellectual functioning (n � 5), beingunexpectedly transferred out of the facility be-fore completing all study measures (n � 5), ordeclining participation during the assent proce-dure (n � 5).

Procedure

The complete protocol was approved by boththe University of Vermont and the VermontState Human Services Institutional ReviewBoards. Before participating in the study, youthparticipants, classroom teachers, and detentionstaff were advised of the project’s voluntarynature, goals, potential benefits, and compensa-tion. Because youth in the detention facilitieswere in legal custody of the state, prior to no-tifying youth of their eligibility to participate,consent for each youth was obtained from De-partment for Children and Families casework-ers. Participants then reviewed and completedassent forms. Eligible youth with signed con-sent had a private meeting with project staff tohave any questions about the study addressedand a representative from the Juvenile Defend-er’s Office was available on site or by phone toensure that youth could have all questions an-swered by a neutral party. Additionally, eachparticipant was notified by the detention direc-tor about periodic meetings held at the center bythe project staff (trained graduate students inclinical psychology) describing the study.Youth received $10 worth of gift certificatesupon completion of the protocol, and teachersand detention staff received an entry in a raffledrawing for each protocol they completed on ayouth. Raffle drawings for one of three awards(worth $25–50) were held after each 25 com-pleted youth protocols.

Project staff administered the protocol toyouth at the detention center. The protocol tookapproximately 2 hours to complete and con-sisted of a two-part, same-day assessment with

a 15-min break in between sections. All self-report measures were administered in a face-to-face interview format using standardized elec-tronic forms on a laptop computer to eliminatebias related to differences in reading ability orunderstanding of items. Additionally, the par-ticipant was provided color-coded cue cards foreach measure indicating the response scale andword anchors for possible responses. The inter-viewer entered participant responses on thecomputerized forms, which generated a data-base for each measure.

Measures

Demographics. Gender and ethnicity werecollected as part of the intake process at thedetention center, along with other demographicvariables not theoretically related to the presentstudy.

Impulsivity (IMP). The Antisocial ProcessScreening Device (APSD; Frick & Hare, 2001)was developed from the Psychopathy Checklist-Revised (PCL-R; Hare, 1991) for use in childand adolescent samples. It has been shown toidentify a subgroup of antisocial youth withtraits similar to those of adult psychopaths inadjudicated, clinical, and community samples(Essau, Sasagawa, & Frick, 2006; Frick, Bodin,& Barry, 2000). The APSD is a 20-item ratingscale with youth, parent, and teacher versions.Informants are asked to rate how true the state-ments are on a 3-point scale. Factor analyseshave identified three correlated factors: a cal-lous unemotional factor (CU; 6 items) relatingto a lack of guilt and remorse, low empathy, andshallow constricted affect; an impulsivity factor(IMP; 5 items) relating to impulsivity, reckless-ness, and a tendency toward boredom; and anarcissism factor (Narc; 7 items) related to thetendency to be charming, boastful, and manipulat-ive (Frick, O’Brien, Wootton, & McBurnett,1994). Only the IMP scale of this measure wasused in the current study to investigate whetherreward responsivity was related to the cogni-tive/impulsivity domain, and to account for em-pirical relations of impulsivity to the BART-Y(Lejuez et al., 2007). The Inventory of Callousand Unemotional Traits (described below) wasused to measure CU traits because the CU scaleof the APSD is of moderate reliability (Poyth-ress et al., 2006). Because narcissism was the-oretically unrelated to the study, this scale was

221REWARD RESPONSIVITY AND CU TRAITS

not used. Cronbach’s alpha for the multiinfor-mant composite of the IMP factor was .58.Generally, studies have indicated good stabilityand internal consistency for this factor (Frick etal., 2000).

Callous Unemotional Traits (CU). TheInventory of Callous and Unemotional Traits(ICU) is a 24-item measure with youth, parent,and teacher versions. The ICU was based on thesix-item CU scale of the APSD. Each of the fourAPSD items that consistently loaded on the CUscale in community and clinical samples wasexpanded into three positively worded and threenegatively worded items, thus comprising theICU. In an initial study using a large communitysample, internal consistency was reported as .77(Essau et al., 2006). Construct validity of theICU is demonstrated by positive relations to theexternalizing scale of the Youth Self Report(YSR; Achenbach, 1991) and to conduct disor-der symptoms from the Bremen Psychopathol-ogy Scale (Essau, 2000), and by negative or norelations to the internalizing scale of the YSRand to the Child and Adolescent Social andAdaptive Functioning Scale (Price, Spence,Sheffield, & Donovan, 2002). Results from thecurrent sample were consistent with those inEssau et al. (2006), with Cronbach’s alpha re-liability coefficient for the multiinformant com-posite at .80.

As noted above, multiinformant compositescores for the APSD (IMP) and ICU (CU) werecomputed from youth, teacher, and staff ratings.Following the recommendation of Piacentini,Cohen, and Cohen (1992) and consistent withpast research and the published APSD manual(Frick & Hare, 2001), these composites wereformed by considering endorsement of an itemby any informant to represent the presence ofthat trait or behavior. Thus, the highest scoreacross informants for each item was used toindex CU traits and IMP. Given that informantsare more likely to be motivated to underreportsocially undesirable traits than to overreportthem (Frick, Cornell, Barry, Bodin, & Dane,2003), this method of compiling multiple-informant data is likely the most sensitive fordetecting the presence of these behaviors.

Reward/Punishment Responsivity. Theadolescent version of the Balloon AnalogueRisk Task (BART-Y; Lejuez et al., 2007) wasdeveloped as a behavioral measure of risk tak-ing; however in the current study, the BART-Y

was conceptualized as a measure of the degreeof reward-seeking behavior, thereby providing ameasure of responsivity of the approach system.The BART-Y has been shown to correlate withcurrently occurring risk behaviors and to haveconvergent validity with sensation seeking andbehavioral dysregulation over and above impul-sivity (Lejuez et al., 2007). In this computerizedtask, participants accumulate points in a tempo-rary bank by pressing a button that inflates asimulated balloon. Each pump delivers pointsinto the temporary bank until the participantschoose to transfer their points into the perma-nent bank. However, the balloons are set toexplode to a predetermined sequence. If theparticipants do not transfer their points into thepermanent bank before exceeding the number ofpumps allotted for that trial, the balloon willexplode and the participants will lose the pointsearned for that trial. The points that are stored inthe permanent bank remain. Three prize boxeslabeled “small,” “medium,” and “large” wereavailable. If youth accrued enough points toreach the “Bonus” mark, they would receive anmp3 player. On completion of the task, youthchose an item from the prize box that corre-sponded to their total accumulated points.

For each nonpopped balloon, the number ofpumps for that trial is recorded. The typicaloutcome variable, Adjusted Average Pumps, isan average of the number of pumps for eachnonpopped balloon. Following the method ofTrotman (2007), a measure of reward respon-sivity was created by computing the differenceof the number of pumps on the trial preceding anonpopped balloon from the number of pumpsfollowing the nonpopped balloon. Because of aceiling effect created by a balloon popping, adifference score was created only when therewere at least two consecutive nonpopped bal-loons. A greater increase in pumps following anonpopped balloon indicates greater rewardresponsivity and thus greater engagement ofthe approach system. Because multiple changescores were computed for each individual (thenumber of change scores corresponds to thenumber of nonpopped balloons), the average ofthe change scores was computed for each par-ticipant. Therefore, each participant had a single“Reward Responsivity” score. A “PunishmentResponsivity” score for each participant wascreated in a similar manner, specifically bycomputing the difference of the number of

222 MARINI AND STICKLE

pumps preceding a popped balloon from thenumber of pumps on the trial following thepopped balloon (i.e., punishment).

Sensation Seeking. The Sensation SeekingScale (SSS-V; Zuckerman, Eysenck, & Eysenck,1978) is a 40-item measure of four factors thathave been shown to comprise the construct ofsensation seeking: thrill and adventure seeking,experience seeking, disinhibition, and suscepti-bility to boredom. Subjects are to choose whichstatement, from a pair of statements, best de-scribes their likes or feelings. The SSS has beenshown to be highly reliable (Zuckerman, 2007)to demonstrate construct and concurrent valid-ity (Zuckerman, 1984) and to correlate withself-reported risk-taking behaviors in adoles-cent samples (Greene, Krcmar, Walters, Rubin,& Hale, 2000; Zuckerman, Eysenck, & Ey-senck, 1978). Reliability in this sample wasconsistent with past studies, with total scalealpha of .79.

Missing Data

There was a small amount of missing data onthe variables included in the study. Missingvalues were a result of data entry errors (i.e., theresearch assistant did not enter the participant’sresponse into the laptop) and were missing atrandom (MAR). Thus, multiple imputation (MI)was deemed suitable to estimate missing data(Little & Rubin, 1997; Tabachnick & Fidell,2007), and Schafer’s NORM software and pro-cedure (Schafer, 1997) were used.

Results

Preliminary Analyses

Table 1 presents means and standard deviationsof the participants’ level of sensation seeking,

impulsivity, CU traits, adjusted average pumps,reward responsivity, and punishment responsiv-ity. Raw data of untransformed variables arepresented. Univariate descriptive statistics ofthe variables were examined for normality,skewness, and outliers. Skewness statistics forthe sensation seeking, impulsivity, reward re-sponsivity, and punishment responsivity vari-ables indicated violations of the normality as-sumption. Sensation seeking and impulsivitywere negatively skewed; therefore followingthe recommendation of Tabachnick and Fidell(2007), each variable was reflected and a squareroot transformation was applied. Additionally,the reward responsivity variable was positivelyskewed and was corrected with a square roottransformation. After the transformations, theskew for each of the variables was substantiallyimproved and the transformed data were used inall analyses. It should be noted that, althoughsensation seeking and impulsivity were re-flected before the transformations, the data wereinterpreted and reported in the remaining anal-yses with the variables reflected back to indicatethe true direction of the relations among thevariables. Each of the variables included in theanalyses was investigated for outliers. All ofCook’s distance influence statistics for the val-ues were less than 1; therefore, we are confidentthat no particular values exerted undue influ-ence on the regression line (Cohen, Cohen,West, & Aiken, 2003).

Zero-order correlations among gender, sensa-tion seeking, impulsivity, CU traits, pumps ad-justed average, reward responsivity, and pun-ishment responsivity were computed to assessfor multicollinearity, and no violations weredetected. As shown in Table 2, CU traits weresignificantly associated with gender (coded 0for girls and 1 for boys), sensation seeking, andIMP. Gender was also significantly associatedwith sensation seeking.

The typically used variable, adjusted averagepumps from the BART-Y, was included in thecorrelation table to examine its relation to theother study variables. It should be noted thatsensation seeking, as measured by the SSS, issignificantly and positively related to BART-Yadjusted average pumps. However, sensationseeking is unrelated to the reward responsivityvariable, thus distinguishing the reward respon-sivity variable from sensation seeking and risktaking and providing support for its construct

Table 1Means and Standard Deviations of UncorrectedVariables

Variable M SD Range

Reward responsivity 7.29 6.87 �4.60–31.20Punishment responsivity �8.31 5.94 �30.13–6.78BART pumps 38.64 14.80 3.43–79.10Sensation seeking 23.07 6.17 5–37Impulsivity 7.93 1.46 3–10CU traits 46.50 6.04 30–64

223REWARD RESPONSIVITY AND CU TRAITS

validity as a distinct measure of the approachsystem.

Multiple Regression Analysis

A hierarchical multiple regression analysiswas conducted to investigate reward responsiv-ity in youth with psychopathic traits. With re-ward responsivity as the outcome variable, gen-der was entered in step 1 of the regression toaccount for any differences in reward respon-sivity that may be attributed to gender. Sensa-tion seeking was entered into step 2 becausesensation seeking has been shown to be relatedto the typical BART outcome variable. Impul-sivity was entered in step 3, and CU traits wereentered into step 4. R-square change from step 3to 4 (squared semipartial correlation of CU withreward responsivity), as well as the directionand magnitude of the beta for step 4, were themain statistics of interest. Results for this anal-ysis are summarized in Table 3. Neither gender,sensation seeking, nor impulsivity was signifi-cantly associated with reward responsivity.Consistent with Blair’s hypothesis of emotionaldysfunction in individuals high in psychopathictraits, CU traits uniquely predicted reward re-sponsivity above and beyond gender, sensation

seeking, and impulsivity (� � �.17, p � .05).Results indicate higher levels of CU traits pre-dict less reward responsivity. Results of theregression indicated a small but significant ef-fect size for CU predicting reduced reward re-sponsivity, with CU traits accounting for 2.5%of the variance in reward responsivity. Al-though not central to the study, the interactionof CU and IMP as well as the interaction of CUand gender were tested in exploratory regres-sion analyses, and neither interaction was sig-nificant.

It should be noted that the strength of theassociation between CU traits and reward re-sponsivity increased from the zero-order corre-lation to the multiple regression when CU traitswere entered after accounting for the varianceattributed to gender, sensation seeking, andIMP. Because this increase in strength from thezero-order correlation to the multiple regressioncan be potentially attributed to a suppressorvariable, an investigation for suppression ef-fects was conducted; however, the criteria forsuppression effects were not met (Cohen &Cohen, 1983; Maassen & Baker, 2001). Be-cause of the gender difference in CU traits (i.e.,males, on average, score higher than females), apartial correlation analysis among gender, CUtraits, and reward responsivity was conducted toinvestigate whether the gender difference in CUtraits decreased the zero-order relation betweenCU traits and reward responsivity. Indeed, afteraccounting for the effect of gender, the relationbetween CU traits and reward responsivity wasconsistent between the partial correlation (r ��.14) and the multiple regression (� � �.17).Therefore, we were confident that the multipleregression and partial correlation analyses indi-cated the true relation between CU traits and

Table 2Correlations Among BART Variables and the Predictor Variables

Variables 1 2 3 4 5 6 7

1. Reward responsivity 1.00 �0.58��� 0.65��� 0.14 0.00 0.02 �0.112. Punishment responsivity 1.00 �0.08 0.04 0.09 0.06 0.073. Adjusted average pumps 1.00 0.27��� 0.17� 0.04 �0.014. Gender 1.00 0.20� 0.05 0.24��

5. Sensation seeking 1.00 0.14 0.22��

6. Impulsivity 1.00 0.35���

7. CU traits 1.00

� p � .05. �� p � .01. ��� p � .001.

Table 3Summary of Hierarchical Regression Analysis forVariables Predicting Reward Responsivity

Variable F B SE B � �R2

Gender 2.91 0.34 0.16 0.18 0.02Sensation seeking 0.07 0.00 0.10 0.00 0.00Impulsivity 0.03 0.15 0.19 0.07 0.00CU traits 3.70� �0.03 0.01 �0.17 0.02

� p � .05.

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reward responsivity after the gender bias in themeasurement of CU traits was removed.

A separate hierarchical regression was con-ducted to examine the relations among the pre-dictors and the punishment responsivity vari-able. As hypothesized, none of the variables inthe model significantly predicted punishmentresponsivity, providing support for the task asimposing only a mild punishment. To furtherensure that the punishment contingency wassmall, as proposed, CU traits were divided intolow and high groups based on gender-specificupper and lower quartiles. Mean levels of pun-ishment responsivity did not differ between thelow and high CU traits groups (Ms � 4.54and 4.58, respectively). The nonsignificant in-crease in pumps following a popped balloonsuggests that the punishment was too mild tosignificantly influence responding in eithergroup.

Discussion

The goal of this study was to investigateresponsiveness of the approach motivationalsystem in youth with CU traits. Consistent withour primary hypothesis, higher levels of CUtraits predicted lower levels of responsivity toreward, above and beyond gender, sensationseeking, and impulsivity. Results suggest thatdeficits associated with emotional responsivitythat may underlie the expression of CU traitsextend to the approach motivational system.Furthermore, because of the lack of associationamong sensation seeking, impulsivity, and re-ward responsivity, these results are consistentwith the idea that a decrease in responsivenessto rewards results from emotionally based def-icits, rather than from executive function/cognitive deficits resulting in impulsivity. Ad-ditionally, that sensation seeking did not predictthe reward responsivity variable created to testour hypothesis provides support for the con-struct validity of the reward responsivity vari-able and its distinction from a measure of risk-taking for which the BART-Y was developed.

These results can be interpreted withinBlair’s (2004, 2006) Integrated Emotion Sys-tems (IES) theory, which suggests that individ-uals with CU traits should be deficient in pro-cessing both positive and negative stimuli(which would lead to deficits in approach andavoidance motivation, respectively). Blair

(2004) hypothesized that individuals with CUtraits present with amygdala dysfunction, whichleads to difficulties in making affect represen-tations. An affect representation refers to “anemotional “tone” that is tagged to a stimulus”(Everett, Cardinal, Parkinson, & Robbins, 2003,p. 234, as cited in Blair, 2006). Thus, it ishypothesized that individuals with CU traitshave difficulty processing incoming affectivecues (that, in turn, activate the approach oravoidance system) because, though they canidentify the cues, these cues do not elicit anemotional response.

Although the effect of CU traits alone wassmall, this was expected because responding torewards captures only a small facet of approachresponsivity that includes other factors such asphysiological responsivity and responding toother emotional stimuli. An important aspect ofwork in this area is to consider CU traits inconjunction with other factors that may contrib-ute to antisocial outcomes. Deficits in emotionalresponsivity are likely one of several underlyingprocesses related to psychopathy in youth. Fu-ture studies incorporating brain imaging tech-niques as well as multiple measures of emo-tional responsivity (positive and negative) willdelineate the particular emotional deficits re-lated to CU traits and investigate whether thesedeficits are, in fact, associated with reducedamygdala responsivity. Additionally, investiga-tions of the structural and functional integrity ofother brain areas associated with reward, suchas the nucleus accumbens and prefrontal cortex,will help to delineate specific reward-relatedimpairments that are to be expected in this pop-ulation.

Additionally, within the motivational frame-work, it is possible to reconcile conflictingevidence of responsivity to rewards in past stud-ies. In tasks that measure responsivity via re-sponse latencies to emotional pictures, such asthat employed by Kimonis and colleagues(2006), it is possible that the positively valenced(pleasure) pictures were not sufficiently arous-ing to elicit a differential response from indi-viduals with and without high levels of psycho-pathic traits. To create an adolescent variant ofthis task, erotic pictures (i.e., nude couples)were removed; however, reported ratings ofarousal in adult samples indicate that eroticpictures produce the highest levels of arousal.Because arousal is related to variations in acti-

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vation of the motivational systems (Lang,1995), it is possible that the removal of eroticpictures could have precluded small differencesbetween groups from emerging.

Nonetheless, the results of the current studyneed to be considered with several limitations inmind. First, this study was cross-sectional indesign; therefore, the temporal relation betweenCU traits and reward responsivity requires test-ing with a longitudinal design. Second, thisstudy was conducted on a sample of adjudicatedyouth; therefore, generalizability of these re-sults to individuals outside the juvenile justicesystem is decreased. On the other hand, therecruitment of an adjudicated sample was astrength of the study because it allowed us torecruit enough participants with high levels ofCU traits to fully test our hypothesis. Addition-ally, this sample was 86% Caucasian, reducingits generalizability to other ethnic groups andprecluding any meaningful analyses of ethnicdifferences. Because the ethnic composition ofour adjudicated sample is not representative ofthe population of adjudicated youth in theUnited States, it is recommended that this studybe replicated with samples of adjudicated ethnicminority youth. Furthermore, the reliability ofthe IMP factor was relatively low (.58); how-ever, because this factor was of secondary in-terest, it was deemed adequate for use in thisstudy.

Despite these limitations, this study wasstrengthened by the large sample size and largenumber of females in the sample. Moreover,this study measured CU traits from multipleinformants and used an experimental task tomeasure responsiveness to rewards. In addition,the task used in the current study allowed for ameasure of simple responsivity to rewards,without the complication of a strong punish-ment contingency or the establishment of a re-ward-dominant response set. Because the re-sults of this study indicate a small effect of CUtraits on approach responsivity, the BART taskwas potentially better able to capture small def-icits in the approach motivational system thatmay have been obscured by tasks that havestrong punishment contingencies, or by thosethat measure attentional or cognitive abilitiesrather than emotional responsivity. Though us-age of the BART-Y was a strength, recent risk-taking modeling approaches, such as the auto-matic response procedure used by Pleskac and

colleagues (2009), may provide an even moreaccurate measure of reward responsivity andrisk-taking. These approaches account for theceiling effect produced on BART-Y trials inwhich the balloon pops yet the participantwould have continued to pump.

Because of advances made in understandingthe development of psychopathic traits, it isbecoming clear that understanding emotionaldeficits in these youth is essential to early de-tection and intervention efforts. Approaches todesigning interventions that incorporate an un-derstanding of causal mechanisms leading toantisocial behavior are critical to improve theeffectiveness of interventions for youth high inCU traits (Stickle & Frick, 2002). Current treat-ment that considers CU traits/emotional dys-function is limited and youth with these traitsshow a poorer response to traditional treatments(Hawes & Dadds, 2005, 2007). It is possiblethat, given support for underresponsivity to re-wards, it may be beneficial to emphasize func-tional analysis to determine what these youthfind rewarding, which would then determinewhich reward contingencies to integrate intotreatment. This type of analysis could be incor-porated into existing treatments that are designedto be tailored for youth with severe behavioralproblems, such as Multisystemic Therapy(Henggeler, Schoenwald, Borduin, Rowland, &Cunningham, 1998) or Contingency Management(e.g., Lott & Jencius, 2009). A tailored approachthat considers emotional and temperamental char-acteristics of the youth may prove to increase theeffectiveness of traditional approaches for thispopulation.

References

Achenbach, T. M. (1991). Manual for Teacher’s Re-port Form and 1991 Profile. Burlington, VT: Uni-versity of VT, Department of Psychiatry.

Barry, T. D., Barry, C. T., Deming, A. M., & Loch-man, J. E. (2008). Stability of psychopathic char-acteristics in childhood: The influence of socialrelationships. Criminal Justice and Behavior, 35,244–262.

Baxter, M. G., & Murray, E. A. (2002). The amyg-dala and reward. Neuroscience, 3, 563–573.

Blair, R. J. R. (1999). Responsiveness to distress cuesin the child with psychopathic tendencies. Person-ality and Individual Differences, 27, 135–145.

226 MARINI AND STICKLE

Blair, R. J. R. (2004). The roles of orbital frontalcortex in the modulation of antisocial behavior.Brain and Cognition, 55, 198–208.

Blair, R. J. R. (2006). Subcortical brain systems inpsychopathy: The amygdala and associated struc-tures. In C. J. Patrick (Ed.), Handbook of psychop-athy (pp. 296–312). New York: Guilford Press.

Blair, R. J. R., Colledge, E., Murray, L., & Mitchell,D. G. V. (2001). A selective impairment in theprocessing of sad and fearful expressions in chil-dren with psychopathic tendencies. Journal of Ab-normal Child Psychology, 29, 491–498.

Blair, R. J. R., Jones, L., Clark, F., & Smith, M.(1997). The psychopathic individual: A lack ofresponsiveness to distress cues? Psychophysiol-ogy, 34, 192–198.

Blair, R. J. R., Peschardt, K. S., Budhani, S., Mitch-ell, D. G. V., & Pine, D. S. (2006). The develop-ment of psychopathy. Journal of Child Psychologyand Psychiatry, 47, 262–275.

Burke, J. D., Loeber, R., & Lahey, B. B. (2007).Adolescent conduct disorder and interpersonal cal-lousness as predictors of psychopathy in youngadults. Journal of Clinical Child and AdolescentPsychology, 36, 334–346.

Burton, R. V., Maccoby, E. E., & Allinsmith, W.(1961). Antecedents of resistance to temptation infour year old children. Child Development, 32,689–710.

Christian, R., Frick, P. J., Hill, N., Tyler, L. A., &Frazer, D. (1997). Psychopathy and conduct prob-lems in children: II. Subtyping children with con-duct problems based on their interpersonal andaffective style. Journal of the American Academyof Child and Adolescent Psychiatry, 36, 233–241.

Cohen, J., Cohen, P., West, S. G., & Aiken, L. S.(2003). Applied multiple regression/correlationanalysis for the behavioral sciences (3rd ed.).Mahwah, NJ: Erlbaum.

Cohen., J., & Cohen, P. (1983). Applied multipleregression/correlation analysis for the behavioralsciences (2nd ed.). Mahwah, NJ: Erlbaum.

Essau, C. A. (2000). Angst und Depression bei Ju-gendlichen (Anxiety and depression in adoles-cents). Habilitationschrift (thesis for a postdoctoraldegree), University of Bremen.

Essau, C. A., Sasagawa, S., & Frick, P. J. (2006).Callous-unemotional traits in a community sampleof adolescents. Assessment, 13, 464–469.

Flor, H., Birbaumer, N., Hermann, C., Ziegler, S., &Patrick, C. J. (2002). Aversive Pavlovian condi-tioning in psychopaths: Peripheral and central cor-relates. Psychophysiology, 39, 505–518.

Fowles, D. C. (1988). Psychophysiology and psy-chopathy: A motivational approach. Psychophysi-ology, 25, 373–391.

Frick, P. J., Bodin, S. D., & Barry, C. T. (2000).Psychopathic traits and conduct problem in commu-

nity and clinic-referred samples of children: Furtherdevelopment of the Psychopathy Screening Device.Psychological Assessment, 12, 382–393.

Frick, P. J., Cornell, A. H., Barry, C. T., Bodin, S. D.,& Dane, H. A. (2003). Callous-unemotional traitsand conduct problems in the prediction of conductproblem severity, aggression, and self-report ofdelinquency. Journal of Abnormal Child Psychol-ogy, 31, 457–470.

Frick, P. J., & Hare, R. D. (2001). The AntisocialProcess Screening Device. Toronto: Multi-HealthSystems.

Frick, P. J., O’Brien, B. S., Wootton, J. M., &McBurnett, K. (1994). Psychopathy and conductproblems in children. Journal of Abnormal Psy-chology, 103, 700–707.

Frick, P. J., Stickle, T. R., Dandreaux, D. M., Farrell,J. M., & Kimonis, E. R. (2005). Callous-Unemo-tional traits in predicting the severity and stability ofconduct problems and delinquency. Journal of Ab-normal Child Psychology, 33, 471–487.

Gorenstein, E., & Newman, J. P. (1980). Disinhibi-tory psychopathology: A new perspective and amodel for research. Psychological Review, 87,301–315.

Greene, K., Krcmar, M., Walters, L. H., Rubin, D. L.,& Hale, J. L. (2000). Targeting adolescent risk-taking behaviors: The contribution of egocentrismand sensation seeking. Journal of Adolescence, 23,439–461.

Hare, R. D. (1991). The Hare Psychopathy Chechlist-Revised. Toronto: Multi-Health Systems.

Hawes, D. J., & Dadds, M. R. (2005). The treatmentof conduct problems in children with callous-unemotional traits. Journal of Consulting andClinical Psychology, 73, 737–741.

Hawes, D. J., & Dadds, M. R. (2007). Stability andmalleability of callous-unemotional traits duringtreatment for childhood conduct problems. Journalof Clinical Child and Adolescent Psychology, 36,347–355.

Henggeler, S. W., Schoenwald, S. K., Borduin,C. M., Rowland, M. D., & Cunningham, P. B.(1998). Multisystemic treatment of antisocial be-havior in children and adolescents. New York:Guilford Press.

Izard, C. E. (1992). Basic emotions, relations amongemotions, and emotion–cognition relations. Psy-chological Review, 99, 561–565.

Jones, A. C., & Gosling, S. D. (2008). Individualdifferences in approach and avoidance motivationin animals. In A. J. Elliot (Ed.), Handbook ofapproach and avoidance motivation (pp. 165–185). New York: Psychology Press.

Kimonis, E., R., Frick, P. J., Fazekas, H., & Loney,B. R. (2006). Psychopathy, aggression, and theprocessing of emotional stimuli in non-referred

227REWARD RESPONSIVITY AND CU TRAITS

girls and boys. Behavioral Sciences and theLaw, 24, 21–37.

Kochanska, G. (1993). Toward a synthesis of paren-tal socialization and child temperament in earlydevelopment of conscience. Child Develop-ment, 64, 325–347.

Kruh, I. P., Frick, P. J., & Clements, C. B. (2005).Historical and personality correlates to the vio-lence patterns of juveniles tried as adults. CriminalJustice and Behavior, 32, 69–96.

Lang, P. J. (1995). The emotion probe: Studies ofmotivation and attention. American Psycholo-gist, 50, 372–385.

Lejuez, C. W., Alkin, W., Daughters, S., Zvolensky,M., Kahler, C., & Gwadz, M. (2007). Reliabilityand validity of the youth version of the BalloonAnalogue Risk Taks (BART-Y) in the assessmentof risk-taking behavior among inner-city adoles-cents. Journal of Clinical Child and AdolescentPsychology, 36, 106–111.

Little, R., & Rubin, D. B. (1997). The analysis ofsocial science data with missing values. Sociolog-ical Methods and Research, 18, 292–326.

Loney, B. R., Frick, P. J., Clements, C. B., Ellis,M. L., & Kerlin, K. (2003). Callous-unemotionaltraits, impulsivity, and emotional processing inadolescents with antisocial behavior problems.Journal of Clinical Child and Adolescent Psychol-ogy, 32, 66–80.

Lott, D. C., & Jencius, S. (2009). Effectiveness ofvery low-cost contingency management in a com-munity adolescent treatment program. Drug & Al-cohol Dependence, 102, 162–165.

Lykken, D. T. (1957). A study of anxiety in thesociopathic personality. Journal of Abnormal andSocial Psychology, 55, 6–10.

Maassen, G. H., & Bakker, A. B. (2001). Suppressorvariables in path models. Sociological Methodsand Research, 30, 241–270.

Marsh, A. A., Finger, E. C., Mitchell, D. G. V., Reid,M. E., Sims, C., Kosson, D. S., . . . Balir, R. J. R.(2008). Reduced amygdala response to fearfulexpressions in children and adolescents with cal-lous-unemotional traits and disruptive behaviordisorders. Archives of General Psychiatry, 165,712–720.

Mitchell, D. G. V., Richell, R. A., Leonard, A., &Blair, R. J. R. (2006). Emotion at the expense ofcognition: Psychopathic individuals outperformcontrols on an operant response task. Journal ofAbnormal Psychology, 115, 559–566.

Newman, J. P., & Kosson, D. S. (1986). Passiveavoidance learning in psychopathic and nonpsy-chopathic offenders. Journal of Abnormal Psy-chology, 95, 257–263.

Newman, J. P., Patterson, C. M., Howland, E. W., &Nichols, S. L. (1990). Passive avoidance in psy-

chopaths: The effects of reward. Personality andIndividual Differences, 11, 1101–1114.

Newman, J. P., Patterson, C. M., & Kosson, D. S.(1987). Response perseveration in psychopaths.Journal of Abnormal Psychology, 96, 145–148.

O’Brien, B. S., & Frick, P. J. (1996). Reward dom-inance: Associations with anxiety, conduct prob-lems, and psychopathy in children. Journal of Ab-normal Child Psychology, 24, 223–240.

O’Brien, B. S., Frick, P. J., & Lyman, R. D. (1994).Reward dominance among children with disrup-tive behavior disorders. Journal of Psychopathol-ogy and Behavioral Assessment, 16, 131–145.

Patrick, C. J. (1994). Emotion and psychopathy: Star-tling new insights. Psychophysiology, 31, 319–330.

Piacentini, J. C., Cohen, P., & Cohen, J. (1992).Combining discrepant diagnostic information frommultiple sources: Are complex algorithms betterthan simple ones? Journal of Abnormal Child Psy-chology, 20, 51–63.

Pleskac, T. J., Wallsten, T. S., Wang, P., & Lejuez,C. W. (2009). Development of an automatic res-pose mode to improve the clinical utility of se-quential risk-taking tasks. Experimental and Clin-ical Psychopharmacology, 16, 555–564.

Polythress, N. G., Douglas, K. S., Falkenbach, D.,Cruise, K., Lee, Z., Murrie, D. C., & Vitacco, M.(2006). Internal consistency reliability of the self-report Antisocial Process Screening Device. As-sessment, 13, 107–113.

Price, C. S., Spence, S. H., Sheffield, J., & Donovan,C. (2002). The development and psychometricproperties of a measure of social and adaptivefunctioning for children and adolescents. Journalof Clinical Child and Adolsecent Psychology, 31,111–122.

Rubia, K., Smith, A. B., Halari, R., Matsukara, F.,Mohammad, M., Taylor, E., & Brammer, M. J.(2009). Disorder-specific dissociation of orbito-frontal dysfunction in boys with pure conduct dis-order during reward and ventrolateral prefrontaldysfunction in boys with pure ADHD during sus-tained attention. American Journal of Psychiatry,166, 83–94.

Salekin, R. T., Rosenbaum, J., & Lee, Z. (2008).Child and adolescent psychopathy: Stability andchange. Psychiatry, Psychology and Law, 15,224–236.

Schafer, J. L. (1997). Analysis of incomplete multi-variate data. London: Chapman & Hall.

Stickle, T. R., & Frick, P. J. (2002). Developmentalpathways to severe antisocial behavior: Interven-tions for youth with callous-unemotional traits.Expert Review of Neurotherapeutics, 2, 511–522.

Tabachnick, B. G., & Fidell, L. S. (2007). Using mul-tivariate statistics (5th ed.). Boston: Allyn & Bacon.

228 MARINI AND STICKLE

Trotman, A. J. M. (2007). The relationship betweenrisk-taking and psychopathy in a sample of inner-city drug users. Unpublished doctoral dissertation,University of Maryland, College Park.

Verona, E., Patrick, C. J., Curtin, J. J., Bradley, M. M.,& Lang, P. J. (2004). Psychopathy and physiologicalresponse to emotionally evocative sounds. Journal ofAbnormal Psychology, 113, 99–108.

Wilkinson, G. S. (1993). Wide Range AchievementTest–Revision 3. Wilmington, DE: Jastak Associ-ation.

Zuckerman, M. (1984). Experience and desire: Anew format for sensation seeking scales. Journal ofBehavioral Assessment, 6, 101–114.

Zuckerman, M. (2007). The sensation seeking scaleV (SSS-V): Still reliable and valid. Personality &Individual Differences, 43, 1303–1305.

Zuckerman, M., Eysenck, S. B., & Eysenck, H. J.(1978). Sensation seeking in England and Amer-ica: Cross-cultural, age, and sex comparisons.Journal of Consulting and Clinical Psychol-ogy, 46, 139–149.

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