The stability of precision grip force in older adults

The exceedingly large grip forces that many older adults employ when lifting objects with a precision pinch grip (Cole, 1991) may compensate for a reduced capability to produce a stable isometric force. That is, their grip force may fluctuate enough from moment to moment to yield grip forces that approach the force at which the object would slip from grasp. We examined the within-trial variability of isometric force in old (68-85 years, n = 13) and young (n = 11) human subjects (a) when they were asked to produce a constant pinch force at three target levels (0.49, 2.25, and 10.5 N) with external support of the arm, hand, and force transducer and (b) when they were asked to grasp, lift, and hold a small test object with a precision grip. Pinch force produced in the first task was equally stable across the two subject groups during analysis intervals that lasted 4 s. The elderly subjects produced grip forces when lifting objects that averaged twice as much as those produced by the young subjects. The force variability during the static (hold) phase of the lift for the old subjects was comparable with that used by the young subjects, after adjusting for the difference in grip force. The failure to observe less stable grip force in older adults contradicts a similar recent study. Differences in task (isometric grip force versus isometric abduction torque of a single digit) may account for this conflict, however. Thumb and finger forces for grip are produced through coactivation of many muscles and thus promote smooth force output through temporal summation of twitches. We conclude that peripheral reorganization of muscle in older adults does not yield increased instability of precision grip force and therefore does not contribute directly to increased grip forces in this population. However, force instability may affect other grip configurations (e.g., lateral pinch) or manipulation involving digit abduction or adduction forces.     

A family study of memory processes and their relations to cognitive test scores

Members of 118 families (456 individuals) who had been tested on several measures of cognitive ability were retested on the same battery in order to determine test-retest reliability. They then were administered the Wechsler Adult Intelligence Scale and tests of visual memory, auditory memory, and figure memory, as well as other measures not discussed herein. Intercorrelations of memory tasks were low to moderate. Factor analysis resulted in a four factor solution. The different factors appeared to represent auditory sequential memory (Factor I); visual memory, as measured psychometrically (Factor II); visual memory, as measured experimentally (Factor III); and figure memory (Factor IV). A second order factor analysis yielded two factors, one consisting of basically psychometric measures of memory and the other of measures of memory obtained in the experimental psychological tradition. Memory measures generally showed low to moderate positive correlations with scores on the cognitive test battery. Significant spouse correlations were found for 3 of the 11 measures of memory. Significant midparent-midchild regressions were found for 9 of the 11 memory measures.     

Loneliness and alcoholism risk in late adolescence: a comparative study of adults and adolescents.

The Short Michigan Alcoholism Screening Test (SMAST) was administered via phone survey to a random sample of subjects 18 years of age and older in a large metropolitan county. Among late adolescents (aged 18 to 20), lonely females had the highest mean score on the SMAST, indicating a higher degree of alcoholism risk than lonely males and nonlonely males and females. Among lonely females, late adolescents scored higher on the SMAST than any other age group. For males, loneliness did not appear to increase alcoholism risk in the late adolescent age group, but did appear to do so during the early and middle adulthood years. The implications of these findings for mental health professionals and adolescent substance abuse treatment personnel are discussed.     

Level and form of psychopathology and the structure of group therapy

Drawing upon concepts derived from ego psychological and object relations psychoanalytic theories of individual development and from a depth group psychology, the present empirical study, a naturalistic field investigation, explored hypothesized relationships between aspects of patients' psychological boundaries and structural features of inpatient therapy groups. More specifically, patients were assessed in terms of their level (i.e., psychotic vs. borderline organization) and form (i.e., anaclitic vs. introjective) of psychopathology. Their perceptions of themselves and of their therapy groups were measured following participation in two kinds of small group treatment designed to differ in terms of degree of internal structuring. Findings, generally supporting the hypotheses, showed the anaclitic borderline patients, in particular, to be most sensitive to structural variations and most adversely affected by an impersonal and highly structured treatment climate. Theoretical and practical implications of these findings were discussed.     

Embracing the “Nation”

The idea of the “nation” has played only a small role in modern political philosophy because of its apparent irrationalism and amoralism. David Miller, however, sets out to show that these charges can be overcome: nationality is a rational element of one’s cultural identity, and nations are genuinely ethical communities. In this paper I argue that his project fails. The defence against the charge of irrationalism fails because Miller works within a framework of ethical particularism which leads to a position of metaethical relativism. A consequence of this relativism is that a community’s moral principles and boundaries of exclusion cannot be rationally justified to those constructed as “outsiders”. The defence against the charge of amoralism fails because Miller does not so much provide an argument to show that nations are ethical communities as assume they are; we are therefore left without resources to discriminate between ethical and unethical nations. I apply these problems to Miller’s treatment of the question of immigration, arguing that it shows that his version of “liberal” nationalism has a tendency to collapse towards a conservative position on such issues. This should not give us any great confidence that the nation, as Miller presents it, should be embraced by modern political philosophy. This revised version was published online in August 2006 with corrections to the Cover Date.     

The Effects of Goal Publicity and Self‐Monitoring on Escalation of Goal Commitment

The current research examines whether the public or private nature of consumer goals affects goal‐commitment escalation following initial goal failure. In particular, the authors explore the moderating role of self‐monitoring. Across three experiments, the authors demonstrate that high self‐monitors are more likely to persist following a public failure than a private failure. However, the public versus private nature of the goal failure does not affect low self‐monitors’ persistence. The authors also explore two boundary conditions for this effect by manipulating the timing of feedback and by testing the role of the perceived value of the incentive for achieving the goal. The article concludes with a discussion of theoretical and managerial insights from this work.     

Stress exposure and stress generation in child and adolescent depression: a latent trait-state-error approach to longitudinal analyses

In 2 longitudinal studies of negative life events and depressive symptoms in adolescents (N = 708) and in children (N = 508), latent trait-state-error structural equation models tested both the stress generation hypothesis and the stress exposure hypothesis. Results strongly suggested that self-reports of depressive symptoms reflect the influence of a perfectly stable trait factor as well as a less stable state factor. Support emerged for both the stress generation model and the stress exposure model. When the state depression factor was modeled as predicting stress, support for the stress generation model appeared to increase with age. When the trait depression factor was modeled as the predictor of stress, support for the stress generation model did not vary with the child's age. In both models, support for the stress exposure remained relatively constant across age.     

Parental enabling attitudes and locus of control of at-risk and honors students

Parental enabling attitudes and behavior interfere with the child's ability to take responsibility for his or her behavior. Enabling is expressed in overprotectiveness and manipulation in which parents insulate their children from unpleasant circumstances and from making mistakes. Unfortunately, these are the very situations in which most children learn self-control, independence, and strategies to correct aberrant behavior. Children of enabling parents often fail to learn that their actions have consequences. The Lynch Enabling Survey for Parents (LESP), a forty-item questionnaire designed to assess the enabling behavior of parents, was evaluated to establish its psychometric properties. In Experiment 1, 416 parents responded to the LESP. The instrument was determined to be reliable (rs = .84 and .92 for split-half and test-retest reliability, respectively) and valid. Factor analysis established four factors, assessing Direct Enabling Parent Involvement, Indirect Nonenabling Parent Involvement, Direct Nonenabling Parent Involvement, and Indirect Enabling Parent Involvement. In Experiment 2, the LESP and the Nowicki-Strickland Locus of Control Scale were used to assess the differences between ninth-grade at-risk and honors students and their parents. The responses of parents of at-risk students on the LESP were significantly more enabling than were the responses of the parents of honors students. At-risk and honors students were also significantly different in their locus of control. Lastly, there was a significant relationship between parents' LESP scores and their children's locus of control scores.