It again seems relatively straightforward to match Siever and Davis's (1991) dimension of affective instability to dysregulation in Gray's BAS or Depue's behavioral facilitation system (BFS), which in turn have been linked to extraversion/positive emotionality. Siever and Davis relate this dimension to the mood disorders on Axis I and to the “dramatic†Cluster B (especially borderline and histrionic personality disorders) on Axis II. As one example of parallel biological findings between these two types of disorders, they cite research documenting similar abnormalities in brain functioning during sleep (e.g., shorter and more variable times between falling asleep and the onset of rapid eye movements associated with dreaming) in both mood disorders and affectively unstable personality disrders.
In contrast to the almost universal association of personality disorder features with the high end of the neuroticism dimension, the two ends of this dimension are predicted to be associated with different disorders (Widiger, 1993). Specifically, histrionic personality disorder is predicted to be most strongly associated with the extraverted end of the dimension and avoidant and schizoid personality disorders with the introverted end. Similarly, when measures of personality and personality disorders were factored together, histrionic and schizoid personality disorders marked opposite ends of an extraversion-intro-version dimension (Wiggins & Pincus, 1994). As noted earlier, avoidant personality disorder loaded mostly strongly on the neuroticism dimension, but it also had a strong secondary loading on introversion.
As mentioned earlier, it is important to distinguish between the level or strength of the positive emotionality/BAS dimension and its variability. Its close association with mood disorder may stem from the fact that both level and variability are important in the manifestation of manic and depressive episodes. These two parameters, however, may be differentially important in personality disorders. When histrionic and schizoid personality disorders mark an extra-version—introversion dimension, the assumption is that the major parameter is level. However, association of this dimension with borderline personality disorder may be based more in the parameter of variability.
In a study of mood variability in nonpatients and patients with major depression, borderline personality disorder, or premenstrual syndrome (PMS), participants completed mood ratings in the morning and evening for 2 weeks (Cowdry, Gardner, O'Leary, Leibenluft, & Rubinow, 1991). Depressed patients had the lowest overall mood, followed by borderline patients; PMS patients did not differ from nonpatients on overall mood level. The greatest overall variability (largest SDs) was seen in PMS patients; depressed patients had the smallest SDs, while those of the borderline patients and nonpatients were between the two extremes. However, on a measure of the degree of randomness of the day-to-day variability, the borderline patients were higher than either depressed or PMS patients, but only the PMS patients differed from nonpatients on this index. Finally, borderline patients also showed the greatest average mood
change from morning to evening; again the depressed patients showed the least variability, with nonpatients and PMS patients falling between the two.
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change from morning to evening; again the depressed patients showed the least variability, with nonpatients and PMS patients falling between the two.
Slavney and Rich (1980) conducted a similar study comparing mood variability in patients with “hysterical personality disorder†versus a control group of “other personality and neurotic diagnoses†(p. 402). Participants completed mood ratings four times a day for 5 days. There was no difference in the overall mood level between the groups, but the patients with hysterical personality disorder showed significantly greater rating-to-rating and day-to-day variability than the control group. Regrettably, both these studies measured mood with a simple “worst mood ever†to “best mood ever†visual analog scale, so the extent to which variation in positive versus negative affect contributed to the overall variability is unknown. When these two affects were measured separately, greater variability in positive than negative affect was found in both a large undergraduate sample and a smaller sample of community-dwelling adult men (Watson & Clark, 1994), but whether these same results would be obtained using psychiatric patients is unknown as well. Nevertheless, it seems possible that poor regulation of the BAS may underlie the hyperreactive moodiness of those with dramatic cluster personality disorders.
Akiskal (1991) has taken the idea of a link between mood and these personality disorders a step further by proposing that many so-called personality disorders are, in fact, unrecognized manifestations of mood disorders. He describes “irritable-cyclothymic,†and “hyperthymic†temperaments that have close parallels in the DSM-IV descriptions of borderline and narcissistic personality disorders, respectively. He also describes a “depressive†temperament that is quite similar to the appended “depressive personality disorder.†The following is taken from Akiskal's description of the irritable cyclothymic patient: “Minor provocation resulted in angry outbursts [and] the emotional storm would not abate for hours or days…. Interpersonal crises are further amplified by their pouting, obtrusive, dysphoric, restless, and impulsive behavior…. A tempestuous life-style that creates interpersonal havoc… [largely due to] the volatile nature of the moods, and the erratic and high-risk behaviors†(pp. 47–48). It seems likely that most clinicians would consider this a description of borderline personality disorder.
Although Akiskal focuses on temperament, and “emphasizes disposition[s] that are closest to the biological underpinnings of drive, affect, and emotion†(p. 43), his full view is that adult personality represents individuals' adaptation to ongoing environmental experiences, given biological predispositions. Indeed, twin studies (and to a lesser extent family and adoption data) have indicated that this dimension not only has a substantial genetic component, but is also—perhaps more than the other dimensions—subject to environmental influences (Nigg & Goldsmith, 1994; Tellegen et al., 1988). Most likely, a complex biopsychosocial model will be needed to account for all of the data.
Impulsivity/Aggression
As in the attempt to link Gray's fight-flight system with the temperamental dimensions discussed earlier, associating Siever and Davis's (1991) dimension of impulsivity/aggression with these dimensions is less clear-cut than for the BIS and BAS. However, as suggested earlier, a reasonable case may be made for linking impulsivity/aggression with the fight-flight system, the personality dimensions of disinhibition, psychoticism, low conscientiousness and low agreeableness, somatic anxiety, alarm reactions, and
the specific negative affect of hostility. It is noteworthy that Zuckerman's (1991) “impulsive unsocialized sensation seeking†dimension also has subfactors of impulsivity and aggression. Finally, Fowles (1993) has noted that recent work in “affective neuroscience†(Panksepp, 1992) suggests the existence of a fourth affective system, in which rage is separated off from panic. Thus, it remains unclear whether one or two dimensions/systems are needed to account for this general domain and, if two, what is the nature of their interrelation, for it seems unlikely that they would be completely independent of each other.
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the specific negative affect of hostility. It is noteworthy that Zuckerman's (1991) “impulsive unsocialized sensation seeking†dimension also has subfactors of impulsivity and aggression. Finally, Fowles (1993) has noted that recent work in “affective neuroscience†(Panksepp, 1992) suggests the existence of a fourth affective system, in which rage is separated off from panic. Thus, it remains unclear whether one or two dimensions/systems are needed to account for this general domain and, if two, what is the nature of their interrelation, for it seems unlikely that they would be completely independent of each other.
Tellegen (1985) has suggested that the dimension he calls Constraint reflects individual differences in a “‘preparedness’ to respond to a range of emotion-re-lated circumstances … with either caution … or with recklessness†(p. 697). This is consistent with Siever and Davis's (1991) characterization of impulsive/ aggressive individuals as action-oriented and as likely to have “difficulty anticipating the effects of their behavior, learning from undesirable consequences of their previous behaviors, and inhibiting or delaying action appropriately†(p. 1650). These characteristics are descriptive of certain personality disorders, especially antisocial and borderline, and an extraordinary amount of relevant research has been conducted on psychopathy. For example, impulsive behavior has been linked with serious delinquency that is stable over time (White et al., 1994). Similarly, men who score high on the Psychopathy Check List (Hare, 1980)—which assesses such characteristics as lack of empathy, shallow affect, and impulsivity—spend more time in prison than nonpsychopathic criminals, at least until about age 40. Most noteworthy in this regard is the dramatic increase in the criminal activity of psychopaths from the early to the late 20s, suggesting marked failure to adapt their behavior following release from incarceration (Hare, McPherson, & Forth, 1988).
There is some indication that cognitive factors play an important role in this domain. For example, research has demonstrated that psychopathic or antisocial individuals have impaired cognitive abilities (Smith, Arnett, & Newman, 1992), fail to leam from negative feedback (Patterson & Newman, 1993), and have difficulty delaying gratification (Sher & Trull, 1994). Antisocial behavior in adolescents—a precursor to adult personality disorder—is strongly predicted by neuropsychological deficits (Moffitt, 1993), especially in higher order “executive†cognitive functions. Neuropsychological dysfunction also has been found in individuals with borderline personality disorder (Judd & Ruff, 1993). Moreover, attention deficit disorder in childhood has been linked to both adolescent conduct disorder (Lilienfeld & Waldman, 1990) and adult antisocial personality disorder (Mannuzza, Klein, Bessler, & Malloy, 1993).
A study of 283 male adoptees revealed that having a delinquent or criminal biologic parent was associated with increased attention deficit disorder, aggressivity, and antisocial personality disorder in the adopted away sons, suggesting a genetic basis for the observed relations (Cadoret & Stewart, 1991). Taken together these data describe a pattern of genetically based neurophysiological and neuropsychological abnormalities that are linked with attentional deficits and poor ability to monitor and self-regulate behavior. The difficulties in self-regu-lation encompass both deficits in inhibiting inappropriate behavior (impulsive behaviors) and in exhibiting strongly active responses (aggressive behaviors). The resulting impulsive/aggressive behavior pattern has been studied primarily in psychopathic or antisocial individuals, but this pattern can be observed in individuals with other personality disorders as well, especially those in the
“dramatic†cluster (borderline, histrionic, and narcissistic). Especially intriguing is the question of why more males than females are diagnosed with antisocial and narcissistic personality disorder, whereas more females than males are diagnosed with borderline and histrionic personality disorder. Perhaps the different socialization experiences of men and women with impulsive/aggressive styles lead to different behavioral expressions of this trait (Lilienfeld, 1992). In any case, it is unlikely that biological factors alone will be able to account for the observed differences.
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“dramatic†cluster (borderline, histrionic, and narcissistic). Especially intriguing is the question of why more males than females are diagnosed with antisocial and narcissistic personality disorder, whereas more females than males are diagnosed with borderline and histrionic personality disorder. Perhaps the different socialization experiences of men and women with impulsive/aggressive styles lead to different behavioral expressions of this trait (Lilienfeld, 1992). In any case, it is unlikely that biological factors alone will be able to account for the observed differences.
Empirical Tests of the Proposed Integrated Model
Linking these three sets of dimensions with the emotion-related criteria of the Axis II personality disorders, several specific hypotheses—shown in table 9-6— can be made about how they should be associated. Specifically, because they contain specific anxiety-related criteria (see table 9-4), schizotypal, avoidant, and dependent personality disorders were hypothesized to correlate with the anxious-inhibited/negative emotionality/BIS dimension. Because affective instability and excessive emotionality are defining characteristics of borderline and histrionic personality disorder, they were hypothesized to correlate with the affective instability/positive emotionality/BAS dimension. Finally, because they contained criteria specifically related to anger, aggression, and impulsivity, paranoid, antisocial, and borderline personality disorders were hypothesized to correlate with the third impulsive-aggressive/disinhibited/fight-flight dimension. These are not, by any means, the only hypotheses that one could make regarding relations between personality disorders and these dimensions (e.g., Widiger's 1993 summary of relations between the personality disorders and the dimensions of the five-factor approach includes many more possibilities), but these seem a priori the most clearly substantiable.
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It is interesting to consider what existing empirical data might be used to test these hypothesized relations. One relevant type of data is the observed pattern of comorbidity among personality disorders: Disorders that are hypothesized to relate to the same dimension should co-occur more frequently than those that are not. An examination of Widiger and Rogers's (1989) review of the comorbidity data provides some support for the stated hypotheses. First, examining the co-occurrence of schizotypal, avoidant, and dependent personality disorders, which were all hypothesized to relate to the anxiety/inhibition dimension, avoidant personality disorder was found to co-occur most frequently with schizotypal (26%) and dependent (20%) personality disorders; however, schizotypal and dependent personality disorders were not highly co-occurent (5%). Second, borderline and histrionic personality disorders—which were hypothesized to share the affective instability dimension—each co-occurred most strongly with the other (46%). Finally, paranoid, antisocial, and borderline personality disorders all were hypothesized to score high on the impulsivity/ag-gression dimension. There was a high degree of overlap between antisocial and borderline personality disorders (26%, which was the greatest overlap for antisocial and second greatest for borderline). However, neither of these disorders overlapped with paranoid personality disorder (1% and 5%, respectively), which was likely due in large part to its very low prevalence (7%) in these data. (By contrast, all of the other disorders compared here were two to five times more prevalent.)
In addition to these tests based on reported comorbidity patterns, data also were available from two independent samples of patients to test these hypotheses. Participants in both samples completed the Structured Interview for DSM-III-R Personality (SIDP-R; Pfohl, Blum, Zimmerman, & Stangl, 1989), a semistructured interview for personality disorders used to rate each DSM-III-R criteria on a four-point scale ranging from “not present†to “prominent symptom.†Ratings for each criteria were summed to form a total score for each Axis II diagnosis. Participants also completed the Schedule for Nonadaptive and Adaptive Personality (SNAP; Clark, 1993), a true-false format, 375-item self-report measure of 15 trait dimensions relevant to personality disorder. Incorporated into the SNAP are the three scales of the GTS (Clark & Watson, 1990) described earlier. table 9-6 also presents the correlations in each sample for each of the hypothesized dimension-disorder relations.
These data confirmed most of the hypothesized relations. Clearly, the anxi-ety/inhibition component of schizotypal personality disorder was not supported, but both avoidant and dependent personality disorder, as hypothesized, were related to negative emotionality. Contrary to hypothesis, positive emotionality was not related to borderline personality disorder and was only weakly related to histrionic personality disorder. Most likely this reflects the fact that the GTS scale taps typical positive mood level, whereas the hypothesized relation is with dysregulation in this mood dimension. Therefore, a measure of mood variability such as Depue's General Behavior Inventory (1987) would probably provide a better test of this hypothesis. The third hypothesis—that the dimension of impulsivity/aggression, operationalized here using the GTS Disinhibition scale, would be related to paranoid, antisocial, and borderline personality disorders—was strongly confirmed.
It is important to emphasize the replicability of the supported relationships. As mentioned, these data sets were collected entirely independently; the only
thing they have in common is their use of the same measures. The larger data set was collected in Texas and represents a heterogeneous patient sample drawn from both inpatient and outpatient settings, including a state hospital, a college counseling center, a community mental health center, a private practice, and a hospital-based family practice clinic. The smaller data set was collected by Pfohl and colleagues in the Department of Psychiatry at the University of Iowa Hospitals and Clinics. Therefore, it is reasonable to conclude that these findings are robust across diverse samples, although whether they would be replicated with different measures of the dimensions and the disorders remains to be tested.
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thing they have in common is their use of the same measures. The larger data set was collected in Texas and represents a heterogeneous patient sample drawn from both inpatient and outpatient settings, including a state hospital, a college counseling center, a community mental health center, a private practice, and a hospital-based family practice clinic. The smaller data set was collected by Pfohl and colleagues in the Department of Psychiatry at the University of Iowa Hospitals and Clinics. Therefore, it is reasonable to conclude that these findings are robust across diverse samples, although whether they would be replicated with different measures of the dimensions and the disorders remains to be tested.
In addition to hypotheses based on the DSM criteria, other hypotheses formulated from the literature may also be examined using Widiger and Rogers (1989) comorbidity data. For example, both borderline and antisocial personality disorders may be characterized as high on the impulsive/aggressive, fight-flight/disinhibition dimension, whereas they should differ on anxiety/inhibi-tion, BIS, negative affect, neuroticism, with antisocial individuals scoring low and borderline individuals scoring high. By contrast, those in the “anxious†Cluster C (avoidant, dependent, and obsessive-compulsive personality disorders) would appear to anchor the high end of the anxiety/inhibition dimension and the constrained end of disinhibition. This analysis suggests there should be the lowest comorbidities between antisocial personality disorder and the Cluster C diagnoses, intermediate comorbidity between borderline personality disorder and the Cluster C diagnoses, and high comorbidities among the Cluster C diagnoses.
Partial confirmation of these hypotheses is again found in Widiger and Rogers's (1989) review, which reported only a 2% overlap of avoidant and dependent personality disorders with antisocial personality disorder, and no overlap at all between antisocial and obsessive-compulsive personality disorder in any of the four studies. Borderline personality disorder showed intermediate level overlap with avoidant and dependent personality disorder (19% each), which were themselves also moderately comorbid (20%). However, none of the diagnoses overlapped with obsessive-compulsive personality disorder, which again was likely due in large part to its very low prevalence (6%). Thus, from a different viewpoint, we again find reasonable confirmation of the hypothesized phenomenological relations. Of course, these analyses do not test the proposed links with the underlying biological dimensions.
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