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Biomedical subjects

J Block

Publications and source records attributed to J Block.

At least 19 recordsLinked to original sources
PubMed1995

On the relation between IQ, impulsivity, and delinquency: remarks on the Lynam, Moffitt, and Stouthamer-Loeber (1993) interpretation.

A recent report by D. Lynam, M. Moffitt, & M. Stouthamer-Loeber (1993) examined the inverse relation between IQ and delinquency and concluded that the observed relation represents "an influence of compromised intelligence on delinquent behavior" (p. 193). Specifically, the role of impulsivity in understanding this relation was discounted. The author considers the conceptual, operational, and analytical bases of the Lynam et al. report and argues that their neurologically based view of "executive dysfunction" as underlying delinquency is selectively portrayed. It is further contended that IQ scores, used as their index of brain-behavior relations, are only remotely related to specifiable neurological functioning. The Lynam et al. conclusion that impulsivity cannot appreciably explain the relation between IQ and delinquency is shown to depend on the analytical approach used. Analyzed alternatively, impulsivity emerges as the more important predictor that can mediate the observed IQ and delinquency relation. Social policy implications of these differing interpretations are noted.

Brain↗
PubMed1995

Overly positive self-evaluations and personality: negative implications for mental health.

The relation between overly positive self-evaluations and psychological adjustment was examined. Three studies, two based on longitudinal data and another on laboratory data, contrasted self-descriptions of personality with observer ratings (trained examiners or friends) to index self-enhancement. In the longitudinal studies, self-enhancement was associated with poor social skills and psychological maladjustment 5 years before and 5 years after the assessment of self-enhancement. In the laboratory study, individuals who exhibited a tendency to self-enhance displayed behaviors, independently judged, that seemed detrimental to positive social interaction. These results indicate there are negative short-term and long-term consequences for individuals who self-enhance and, contrary to some prior formulations, imply that accurate appraisals of self and of the social environment may be essential elements of mental health.

Adaptation, Psychological↗
PubMed1995

A contrarian view of the five-factor approach to personality description.

The 5-factor approach (FFA) to personality description has been represented as a comprehensive and compelling rubric for assessment. In this article, various misgivings about the FFA are delineated. The algorithmic method of factor analysis may not provide dimensions that are incisive. The "discovery" of the five factors may be influenced by unrecognized constraints on the variable sets analyzed. Lexical analyses are based on questionable conceptual and methodological assumptions, and have achieved uncertain results. The questionnaire version of the FFA has not demonstrated the special merits and sufficiencies of the five factors settled upon. Serious uncertainties have arisen in regard to the claimed 5-factor structure and the substantive meanings of the factors. Some implications of these problems are drawn.

Factor Analysis, Statistical↗
PubMed1990

Adolescent drug use and psychological health. A longitudinal inquiry.

The relation between psychological characteristics and drug use was investigated in subjects studied longitudinally, from preschool through age 18. Adolescents who had engaged in some drug experimentation (primarily with marijuana) were the best-adjusted in the sample. Adolescents who used drugs frequently were maladjusted, showing a distinct personality syndrome marked by interpersonal alienation, poor impulse control, and manifest emotional distress. Adolescents who, by age 18, had never experimented with any drug were relatively anxious, emotionally constricted, and lacking in social skills. Psychological differences between frequent drug users, experimenters, and abstainers could be traced to the earliest years of childhood and related to the quality of parenting received. The findings indicate that (a) problem drug use is a symptom, not a cause, of personal and social maladjustment, and (b) the meaning of drug use can be understood only in the context of an individual's personality structure and developmental history. It is suggested that current efforts at drug prevention are misguided to the extent that they focus on symptoms, rather than on the psychological syndrome underlying drug abuse.

Adaptation, Psychological↗
PubMed1990

Physical and sexual abuse in adolescent girls with borderline personality disorder.

Recent investigations suggest that a history of childhood sexual abuse may be associated with borderline personality disorder. This study compares a group of female adolescents diagnosed as borderline with a control group for history of physical and sexual abuse. History of both forms of abuse, particularly sexual, distinguishes the two groups. Results point to the impact of repeated trauma on character structure, cognitive functioning, and Axis II symptomatology.

Adolescent↗
PubMed1989

Mild versus definite osteoporosis: comparison of bone densitometry techniques using different statistical models.

The purpose of this investigation was to determine the ability of three bone densitometry techniques to discriminate subjects with mild vertebral deformities from those with definite compression fractures. We determined bone mineral density (BMD) in 68 postmenopausal women by quantitative computed tomography (QCT) and dual-photon absorptiometry (DPA) of the spine, as well as single-photon absorptiometry (SPA) of the radius. Forty four individuals were classified as having mild deformities of the spine and 24 were considered to have definite vertebral compressions. Several statistical approaches were used to compare these subgroups and to estimate the relative risk of vertebral fracture. Included among these were percent decrements and zeta-scores, ROC curves, odds ratio estimations, and logistic regression analysis. Individuals with definite vertebral fractures had lower bone mineral density at all sites, but measurement of radial compact bone by SPA failed to reach significance. Using ROC analysis to distinguish mild deformities from true compressions, we found that measurement of spinal trabecular bone by QCT to be the most sensitive discriminator; although measurement of spinal integral bone by DPA also gave satisfactory discrimination, whereas assessment of radial compact bone did not adequately differentiate patients with mild deformities from those with definite compressions. Likewise, we found determination of spinal trabecular bone to be the most robust predictor of relative risk of definite fracture using either odds ratios or logistic regression analysis. Measurement of BMD in the peripheral cortical skeleton offered no predictive power for true vertebral fracture. We concluded that direct assessment of the spine, particularly of the trabecular portion, offered the strongest discrimination and relative risk prediction for definite osteoporotic fractures compared with milder forms of this condition.

Aged↗
PubMed1989

Critique of the act frequency approach to personality.

Evaluates the the act frequency approach (AFA), noting that retrospective self-reports rather than behavioral acts are studied; act context and meaning are not considered; the AFA self-report inventories are incompletely developed and are psychometrically unsound; the AFA claim of absolute measurement of dispositions is insupportable; many of the self-report act statements used are technically unacceptable or conceptually unwarranted; the research agenda of the AFA primarily involves only "internal analyses" of self-report "act" inventories and indices and proposes the further creation of "act" inventories to index thousands of conceptually unorderable dispositions. Were the problems involved in the current implementation of the AFA to be resolved, various large conceptual problems presently besetting the approach then would have to be confronted.

Behavior↗
PubMed1989

The role of ego-control, ego-resiliency, and IQ in delay of gratification in adolescence.

The delay-of-gratification behavior of 104 14-year-old Ss (54 girls and 50 boys) was assessed in an experiment in which each subject chose between immediate monetary payment and larger, delayed payment on 5 occasions. Personality data were obtained on these adolescents in the form of California Adult Q-Set ratings made by several research examiners who were blind to the subjects' delay behavior. The number of delayed payments chosen was strongly correlated with these personality ratings, within both sexes. Ss who exhibited the most delay of gratification tended to be independently described as responsible, productive, ethically consistent, interested in intellectual matters, and overly controlled. They tended not to be described as unable to delay gratification, rebellious, unpredictable, self-indulgent, or hostile. Delay behavior in both sexes was also correlated positively with IQ and with Q-sort-derived indexes of ego resiliency and ego control. The relationship between ego control and delay behavior was particularly strong after both IQ and ego resiliency were partialled. These results were interpreted as reflecting the fundamental importance of both cognitive skillfulness and impulse control for adaptive delay behavior in situations that contain strong motivational inducements.

Adolescent↗
PubMed1988

Longitudinally foretelling drug usage in adolescence: early childhood personality and environmental precursors.

Drug usage in early adolescence (age 14) was related to concurrent and preschool personality characteristics for a sample of 54 girls and 51 boys. The personality concomitants and antecedents of drug use differed somewhat as a function of gender and the drug used. At age 14, for both sexes, the use of marijuana was related to ego undercontrol, while the use of harder drugs reflected an absence of ego-resiliency, with undercontrol also a contributing factor. At ages 3/4, subsequent adolescent drug usage in girls related to both undercontrol and lower ego-resiliency. In boys, adolescent drug usage related strongly, during their nursery school years, to undercontrol and with resiliency having no long-term implications. Early family environment related to adolescent drug usage in girls but not in boys. Drug usage in adolescent girls was related to homes earlier identified as unstructured and laissez-faire, where there was little pressure to achieve. Drug usage related to other substance use and, in boys, to IQ decline from age 11 to age 18. Implications of these results for contemporary views regarding adolescent drug usage are discussed.

Adolescent↗
PubMed1988

Parental agreement on child rearing during early childhood and the psychological characteristics of adolescents.

In previous research, an index of parental agreement regarding child-rearing orientations was found to relate to the quality of children's psychological functioning from 3 to 7 years of age. For this study, the parental agreement index, derived when their children were 3 years old, was related to a variety of psychological measures and personality descriptions obtained when the children were adolescents. Reliable differences were found in the patterning of relations for boys and girls wherein parental agreement during early childhood was associated with tested intelligence, aspects of moral judgment, and dimensions of personality derived from self-reports for boys but not for girls. For adolescent girls, early parental agreement was associated with the congruence of "self" and "ideal-self" descriptions (i.e., self-esteem). For both girls and boys, parental agreement was associated with personality descriptions provided by observers; however, it was only in the sample of girls that early parental agreement significantly correlated with Q sort criterion scores referencing ego-undercontrol and ego-resiliency. These findings suggest that early family socialization experiences are importantly but differently salient for boys and girls with respect both to psychological content and the developmental timing of effects. The data suggest that socialization researchers consider the likelihood that developmental paths to competence differ markedly for girls and boys.

Adolescent↗
PubMed1988

The mechanical characteristics of the collateral ligaments of the human ankle joint.

In the present study, the tensile mechanical properties of all of the collateral ligaments of the human ankle joint were determined, in vitro, from tensile tests conducted on 120 ligaments obtained from 20 fresh lower limbs. The ultimate load of the lateral collateral ligaments increased in an anteroposterior sequence, with the anterior fibulotalar ligament less than the fibulocalcaneal ligament and less than the posterior fibulotalar ligament. For the medial collateral ligaments, the increasing order of ultimate load was found to be tibiocalcaneal ligament, tibionavicular ligament, tibiospring ligament, posterior tibiotalar ligament. The posterior tibiotalar ligament and tibiospring ligament, so frequently neglected in the anatomical and orthopaedic literature, demonstrated the highest yield force and ultimate load of all of the collateral ligaments of the ankle. Additionally, the tibiospring ligament showed high yield and ultimate elongation properties probably related to its distal attachment to the spring ligament. The fibulocalcaneal ligament was found to have high linear elastic modulus suggesting some type of unique material properties or internal fiber organization. Knowledge of the mechanical characteristics of the ligaments of the ankle joint contributes to an understanding of their normal function, pathomechanics of injury, and their optimal surgical reparative procedure and reconstructive material. A knowledge of the normal mechanical properties of the ankle ligaments provides a data base to evaluate which of the multiplicity of present tendon graft materials has mechanical properties similar to those of the ligaments to be replaced. Those tendon grafts will be the most suitable for replacement of specific ligaments. Finally, data on the mechanical properties of these ligaments offer the possibility for evaluating any future biological or prosthetic grafts.

Aged↗
PubMed1987

Testing aspects of Carl Rogers's theory of creative environments: child-rearing antecedents of creative potential in young adolescents.

Longitudinal data involving 106 children and their parents were used to test preschool child-rearing implications of Carl Rogers's theory of creativity-fostering environments (Rogers, 1954). Indices were developed for each parent and for each mother-father combination that reflected the degree to which the parents' child-rearing practices and interactions with their preschool children matched the recommendations implicit in Rogers's description of a creativity-fostering environment. The three indices of Rogers-prescribed child-rearing practices each correlated positively (rs = .38 to .46) and significantly (all ps less than .001) with a composite index of creative potential in early adolescence, 7 to 11 years later. Rogers-prescribed preschool child-rearing practices also emerged as significant antecedents of adolescent creative potential in regression/path analyses that held constant the influence of sex, preschool intelligence, and preschool creative potential. Theoretical and methodological aspects of the study are discussed.

Adolescent↗