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D N Jackson

Publications and source records attributed to D N Jackson.

At least 19 recordsLinked to original sources
PubMed2000

What is beyond the big five? Plenty!

In a recent analysis of personality data, Saucier and Goldberg (1998) sought to answer the question, What is beyond the Big Five? Those authors evaluated numerous clusters of English person-descriptive adjectives that have been suspected of referring to non-Big Five dimensions of personality. Their results led them to conclude that most, if not all, traits of personality can be adequately subsumed within the Big Five factor space. In contrast, our reanalysis of Saucier and Goldberg's own data, using a more realistic criterion for deciding on whether a variable does or does not fall within a particular factor space, contradicts their claim. We are led to the conclusion that there are plenty of dimensions of behavior beyond the Big Five.

Female↗
PubMed2000

Acute head-down tilt decreases the postexercise resting threshold for forearm cutaneous vasodilation.

The purpose of this study was to evaluate the role of baroreceptor control on the postexercise threshold for forearm cutaneous vasodilation. On four separate days, six subjects (1 woman) were randomly exposed to 65 degrees head-up tilt and to 15 degrees head-down tilt during a No-Exercise and Exercise treatment protocol. Under each condition, a whole body water-perfused suit was used to regulate mean skin temperature (T(sk)) in the following sequence: 1) cooling until the threshold for vasoconstriction was evident; 2) heating ( approximately 7.0 degrees C/h) until vasodilation occurred; and 3) cooling until esophageal temperature (T(es)) and (T(sk)) returned to baseline values. The Exercise treatment consisted of 15 min of cycling exercise at 70% maximal O(2) uptake, followed by 15 min of recovery in the head-up tilt position. The No-Exercise treatment consisted of 30 min resting in the head-up tilt position. After the treatment protocols, subjects were returned to their pretreatment condition, then cooled and warmed again consecutively. The calculated T(es) threshold for cutaneous vasodilation increased 0.24 degrees C postexercise during head-up tilt (P < 0.05), whereas no difference was measured during head-down tilt. In contrast, sequential measurements without exercise demonstrate a time-dependent decrease for head-up tilt (0.17 degrees C) and no difference for head-down tilt. Pretreatment thresholds were significantly lower during head-down tilt compared with head-up tilt. We have shown that manipulating postexercise venous pooling by means of head-down tilt, in an effort to reverse its impact on baroreceptor unloading, resulted in a relative lowering of the resting postexercise elevation in the T(es) for forearm cutaneous vasodilation.

Adult↗
PubMed1996

Heritability of personality disorder traits: a twin study.

Genetic and non-genetic influences on the hierarchy of traits that delineate personality disorder as measured by the Dimensional Assessment of Personality Problems (DAPP-DQ) scale were examined using data from a sample of 483 volunteer twin pairs (236 monozygotic pairs and 247 dizygotic pairs). The DAPP-DQ assesses four higher-order factors, 18 basic dimensions and 69 facet traits of personality disorder. The correlation coefficients for monozygotic and dizygotic twin pairs ranged from 0.26 to 0.56 and from 0.03 to 0.41, respectively. Broad heritability estimates ranged from 0 to 58% (median value 45%). Additive genetic effects and unique environmental effects emerged as the primary influences on these scales, with unique environmental influences accounting for the largest proportion of the variance for most traits at all levels of the hierarchy.

Adolescent↗
PubMed1994

Categorical distinctions in the study of personality disorder: implications for classification.

This article discusses the historical underpinnings of psychiatric classification and examines empirical evidence relevant to (a) whether personality disorders are distinct from each other and from normal personality and (b) whether personality disorders should be classified separately from other mental disorders. At the phenotypic level, research evidence strongly supports the use of a dimensional model to delineate personality disorders; evidence about their genotypic representation is less conclusive though still supportive. Neither empirical nor rational arguments indicate strong justification for separating personality disorders from other mental disorders, as has been done in both the third and fourth editions of the Diagnostic and Statistical Manual of Mental Disorders. Distinctions between abnormal and disordered personality are considered, and suggestions are made for more satisfactory diagnostic classificatory schemes.

Comorbidity↗
PubMed1993

Genetic and environmental contributions to dimensions of personality disorder.

OBJECTIVE: The authors estimated the heritability of the basic dimensions of personality disorder and the relative proportions of the variance attributable to genetic and environmental sources. METHOD: The subjects were 175 volunteer twin pairs (90 monozygotic and 85 dizygotic) from the general population. Each twin completed the Dimensional Assessment of Personality Pathology, a questionnaire that assesses 18 dimensions of personality disorder. The questionnaire was developed on the basis of factor analytic studies that identified a stable structure underlying personality disorders in clinical and nonclinical subjects. Structural equation model-fitting methods were used to estimate the influence of additive genetic, common environmental, and unique environmental effects. RESULTS: The estimates of broad heritability ranged from 0%, for conduct problems, to 64%, for narcissism. Behaviors associated with submissiveness and attachment problems had low heritability. For most dimensions, the best-fitting model was one that specified additive genetic and unique environmental effects. CONCLUSIONS: These results are similar to those reported for normal personality and suggest a continuity between normal and disordered personality.

Adolescent↗
PubMed1992

Factorial structure of traits delineating personality disorders in clinical and general population samples.

Categorical and dimensional models for classifying personality disorders were evaluated by comparing the structure of personality pathology in a clinical sample (n = 158) with the structure in a general population sample (n = 274). Subjects completed 100 personality scales. Separate factor analyses revealed similar structures in the 2 samples. An underlying structure in a combined sample showed limited agreement with the concepts of the Diagnostic and Statistical Manual of Mental Disorders (American Psychiatric Association, 1987). Fifteen factors were retained: Generalized Distress, Rejection, Restricted Expression, Compulsivity, Stimulus Seeking, Insecure Attachment, Diffidence, Intimacy Problems, Oppositionality, Interpersonal Disesteem, Conduct Problems, Cognitive Dysfunction, Affective Reactivity, Narcissism, and Social Apprehensiveness. The results are consistent with a dimensional representation of personality disorder.

Adult↗
PubMed1992

Guidelines for developing, evaluating, and revising the classification of personality disorders.

The authors suggest ways to improve the classification of personality disorders by changing the way the classification is developed, evaluated, and modified. Specific proposals are intended to establish a system that can be evaluated and revised so that it successively approximates a valid system. The importance of stating the principles underlying the classification is emphasized. These principles include: the conception of personality disorder underlying each diagnosis, the structure used to define diagnoses, the nature of diagnostic items, and the model for organizing diagnostic decisions. A distinction is drawn among the theoretical, measurement, and diagnostic models underlying each diagnosis. The substantive aspects of the classification are discussed in terms of the evidence required to validate diagnostic concepts. It is argued that the first step in developing a classification is to ensure the content validity of diagnostic concepts because this is a prerequisite for other components of validity. Evaluation and revision of the classification are discussed in terms of the importance of convergent and discriminant evidence. It is recommended that the classification be evaluated and revised using criteria derived from the theoretical and measurement models associated with each diagnosis. It is also recommended that the classification be evaluated in terms of the degree to which diagnostic constructs are consistent across clinicians, different sets of diagnostic exemplars, and different samples of patients. Realization of these aims should provide a classification that may be verified, modified, or disproved in the scientific tradition.

Guidelines as Topic↗
PubMed1992

The dimensionality of Type A behavior within a stressful work simulation.

The present study was conducted to examine the dimensionality of overt Type A behaviors elicited in a simulated stressful work environment. University students played a managerial role while being subjected to time and work-load pressures, and completed the Survey of Work Styles (SWS; Jackson & Gray, 1989). Eighteen behaviors, coded by two raters based on audiovisual recordings, yielded relatively high interrater reliabilities. Principal components analysis revealed four primary factors: Hurriedness, Irritability, Tension of the Lower Extremities, and Restlessness. These factors contribute to an understanding of Type A behavior in that they are the first to be derived from a purely observational approach rather than a combination of observational and self-report methods. Consistent with previous research, differential correlations between the factors and the SWS subscales supported a multi-dimensional interpretation of the Type A behavior pattern. Present findings are compared to those of previous studies of Type A dimensionality.

Adolescent↗
PubMed1991

Dimensions of personality pathology.

The reliability of DSM-III-R diagnoses of personality disorders is poor and their validity has yet to be established. There is little evidence that the features of personality pathology cluster into these diagnostic entities. For these reasons, it is important to explore alternative ways of classifying personality disorders. In this preliminary study, reliable scales were developed to assess 100 personality dimensions which were systematically developed. The factorial structure underlying the dimensions was evaluated in a heterogeneous sample of 110 subjects from the general population. Sixteen components, accounting for 81.4% of the variance, were retained for rotation to oblique structure. The components were labelled social avoidance, narcissism, insecure attachment, compulsive behaviours, interpersonal disesteem, mobility, anxiousness, conduct problems, stimulus seeking, identity disturbance, self-harm, rejection, diffidence, and hypersensitivity. Two components were not interpreted because they only had one or two salient loadings.

Adult↗
PubMed1990

Fetal gastroschisis and omphalocele: is cesarean section the best mode of delivery?

There has always been controversy regarding the mode of delivery of fetuses with abdominal wall defects. Prior studies may have been biased in this evaluation as a result of the effects of delay in repair, transport of the fetus to level III facilities, and antenatal diagnosis compared with an unsuspected diagnosis. The purpose of this study was to evaluate mode of delivery at level III institutions with access to complete care to determine if cesarean section improved outcome. One hundred eight infants were treated in the study period for abdominal wall defects. Fifty-six infants met all criteria for admission to the study. No difference in neonatal morbidity or mortality was identified. No difference was found in infants who were born by elective cesarean section compared with infants delivered after labor ensued. In conclusion, we found no evidence that cesarean section or avoidance of labor improved outcome in fetuses with uncomplicated abdominal wall defects.

Abdominal Muscles↗
PubMed1990

Chronic parenting stress: moderating versus mediating effects of social support.

The present study contrasted the widely cited "buffer" model of social support with an alternative mediator model. Distinctions were drawn between the functions of social support under chronic vs. acute stress conditions, and between situation-specific stressors and major life events. Ongoing parenting stress was assessed in 96 mothers of deaf children and 118 matched controls. Tests of the competing models showed no moderating effects for social support. However, path analyses suggested that social support mediated the relationship between stressors and outcomes. Chronic parenting stress was associated with lowered perceptions of emotional support, and greater symptoms of depression and anxiety. Furthermore, parenting stress accounted for a substantial proportion of the variance in psychological distress scores in contrast to life event stress, which was only weakly related to psychological outcomes. The implications of mediational models for understanding adaptation to chronic stress are discussed.

Adaptation, Psychological↗
PubMed1990

Identification of a coronary-prone profile for business managers: comparison of three approaches to Type A assessment.

This study compares three approaches to Type A assessment for identifying a coronary-prone profile for business managers. The Survey of Work Styles (SWS), a profile measure of the Type A behavior pattern, was compared with the Structured Interview (SI), a categorical measure, and with the Jenkins Activity Survey (JAS) and Framingham Type A Scale, both continuous measures. The blood pressure, heart rate, and cardiac effort of 163 middle-aged male business managers (107 of whom were classified as Type A by the SI) were assessed during the SI. Neither the classification by the SI of the subjects into Type A and non-Type A groups nor Type A1, A2, X, B3, and B4 revealed differences in physiological arousal. Similarly, no relationship was found between physiological variables and Type A behavior that was assessed on a continuum by the JAS or Framingham Type A Scale. When business managers were classified by the SWS according to their pattern of Type A components, however, the results showed that men high on Anger but low on Competitiveness and Job Dissatisfaction had significantly higher levels of systolic blood pressure during the SI. The importance of recognizing individual differences in the expression of Type A behavior when assessing coronary-prone physiological reactivity is discussed.

Adult↗
PubMed1990

The structured nonverbal assessment of personality.

This article describes the development of a structured nonverbal measure of personality based on Murray's (1938) system of needs. The items of the Nonverbal Personality Questionnaire consist of line drawings of a central figure performing trait-relevant behaviors in specific situations; respondents are asked to indicate the likelihood of engaging in similar behaviors. The nonverbal form was administered to three Canadian samples of respondents and one Finnish sample. Reliability and validity data for the initial item pool and for a revised form are reported. The utility of the nonverbal inventory for cross-cultural and theoretical work in personality is discussed.

Adult↗
PubMed1989

Validation of the survey of work styles: a profile measure of the type A behaviour pattern.

The present study compares the Type A classification accuracy of the Jenkins Activity Survey (JAS), The Framingham Type A Scale, and a new Type A behaviour pattern (TABP) measure. The Survey of Work Styles (SWS), a self-report measure of the TABP, was developed using a construct approach to scale construction. It consists of six content scales. Impatience, Anger, Work Involvement, Time Urgency, Job Dissatisfaction and Competitiveness. In addition to the six content scales, a seventh scale, Scale A, is comprised of items empirically selected to relate to the Rosenman Structured Interview. In the present study the SWS was found to be significantly related to both the JAS, and the Framingham Type A Scale in a sample of 163 business managers. Median reliability of the SWS subscales was 0.82, and for the total scale 0.90. Discriminant function analysis using cross validational jackknifing procedures resulted in a classification accuracy of 83% of the Type A managers in relation to the Structured Interview. Classification using the SWS was found to correlate significantly higher with the Structured Interview than did either classification with the JAS or with the Framingham Type A Scale. Modal profile analysis yielded three independent bipolar typal dimensions, indicating that a single dimension or classification of the TABP represents an oversimplification of a complex behaviour pattern. These results support the reconceptualization of the TABP in terms of distinct facets and profile patterns.

Adult↗
PubMed1987

Common dimensions of psychopathology from the MMPI and the Basic Personality Inventory.

The MMPI and the Basic Personality Inventory (BPI) were administered to 235 male hospitalized psychiatric patients who were undergoing treatment for alcoholism. The 13 validity and clinical scales from the MMPI and the 12 scales from the BPI were subjected to principal axes factor analysis and Varimax rotation. The five factors retained for interpretation, which accounted for more than 96% of the common variance, each had loadings from both the MMPI and the BPI. Factors were identified as Inadequate Impulse Control, Generalized Anxiety, Depression and Somatization, Psychotic Processes, and Depressed Withdrawal. Given the high percentage of variance accounted for by the factors, it was concluded that the MMPI and BPI measure the same broad domain of psychopathology.

Adult↗
PubMed1986

Clinical judgments of depression.

In an effort to reevaluate Gough's (1954) classic study of common misconceptions about neuroticism, an investigation was undertaken of the degree to which judges could simulate the Basic Personality Inventory (BPI) responses of a clinically depressed patient group. Judgments were recorded of the probability of responding to each of 240 BPI items by a total of 56 university student judges. Judges were assigned randomly to one of two information conditions, one that had only the label "clinical depression" and another that had, in addition, a more extensive definition. Judgmental profiles of depressed patients indicated very high reliabilities (.99) across information conditions, a high association with actual profiles of clinically depressed patients, and differentiation from other psychiatric patients and normal controls. Results were interpreted as supporting the accuracy of judgments of psychopathology, particularly when certain preconditions are met, namely, the use of a meaningful construct of psychopathology and the prediction of behavior relevant to that construct.

Depressive Disorder↗