Fragile self-esteem and affective instability in posttraumatic stress disorder

Temporal fluctuations in self-esteem and affect are prominent features of several clinical conditions (e.g., depression), but there is an absence of empirical work examining their role in posttraumatic stress disorder (PTSD). Individuals who experience large fluctuations in self-evaluations and affect are considered more vulnerable to psychopathology than individuals able to adequately modulate their self-image and emotional responses. We examined the relevance of self-esteem and affective instability to PTSD. Veterans with and without PTSD completed 14 daily ratings of self-esteem, positive affect, negative affect, and gratitude. Compared to veterans without PTSD, veterans with PTSD exhibited more temporal fluctuations in self-esteem, negative affect, and gratitude, with a smaller effect for positive affect. For all veterans, self-esteem and negative affective instability was associated with diminished well-being. Except for self-esteem instability, most findings were substantially reduced after accounting for variance attributable to PTSD diagnoses and mean intensity levels over the 14-day monitoring period. These data suggest self-esteem instability is important in understanding the lives of veterans with and without PTSD.     

Postural control after unexpected external perturbation: Effects of Parkinson’s disease subtype

Different clinical subtypes of Parkinson’s disease (PD) have long been recognized. Recent studies have focused on two PD subtypes: Postural Instability and Gait Difficulty (PIGD) and Tremor Dominant (TD). PIGD patients have greater difficulties in postural control in relation to TD. However, knowledge about the differences in reactive adjustment mechanisms following a perturbation in TD and PIGD is limited. This study aimed to compare reactive postural adjustments under unexpected external perturbation in TD, PIGD, and control group (CG) subjects. Forty-five individuals (15 TD, 15 PIGD, and 15 CG) participated in this study. Postural perturbation was applied by the posterior displacement of the support surface in an unexpected condition. The velocity (15 cm/s) and displacement (5 cm/s) of perturbation were the same for all participants. Center of pressure (CoP) and center of mass (CoM) were analyzed for two reactive windows after the perturbation (0–200 ms and 200–700 ms). The Bonferroni post hoc test indicated a higher range of CoP in the PIGD when compared to the CG (p = 0.021). The PIGD demonstrated greater time to recover the stable posture compared to the TD (p = 0.017) and CG (p = 0.003). Furthermore, the TD showed higher AP-acceleration peak of CoM when compared to the PIGD (p = 0.048) and CG (p = 0.013), and greater AP-acceleration range of CoM in relation to the CG (p = 0.022). These findings suggest that PD patients present worse reactive postural control after perturbation compared to healthy older individuals. CoP and CoM parameters are sensitive to understand and detect the differences in reactive postural mechanisms in PD subtypes.     

Is apparent instability a guiding feature in visual search?

ABSTRACT

Humans are quick to notice if an object is unstable. Does that assessment require attention or can instability serve as a preattentive feature that can guide the deployment of attention? This paper describes a series of visual search experiments, designed to address this question. Experiment 1 shows that less stable images among more stable images are found more efficiently than more stable among less stable; a search asymmetry that supports guidance by instability. Experiment 2 shows efficient search but no search asymmetry when the orientation of the objects is removed as a confound. Experiment 3 independently varies the orientation cues and perceived stability and finds a clear main effect of apparent stability. Experiment 4 shows converging evidence for a role of stability using different stimuli that lack an orientation cue. However, here both search for stable and unstable targets is inefficient. Experiment 5 is a control for Experiment 4, showing that the stability effect in Experiment 4 is not simple side-effects of the geometry of the stimuli. On balance, the data support a role for instability in the guidance of attention in visual search. (184 words)     

Age differences in instability, contingency, and level of self-esteem across the life span

We investigated age differences in instability, contingency, and level of self-esteem from age 13 to 72 years, using data from 1386 individuals who participated in a diary study over 25 days. Instability and contingency of self-esteem decreased from adolescence to old age, whereas level of self-esteem increased. Big Five personality traits predicted the level, but not the slope, of the trajectories of self-esteem characteristics. Age differences in self-esteem characteristics did not merely reflect age differences in instability and level of positive and negative affect. Finally, self-esteem characteristics showed a stable pattern of interrelations across the life span. Overall, the findings suggest that people’s self-esteem tends to become better adjusted—i.e., more stable, less contingent, and higher—across the life course.     

Can Rosenberg’s (1965) Stability of Self Scale capture within-person self-esteem variability? Meta-analytic validity and test–retest reliability

Can Rosenberg’s (1965) Stability of Self Scale (RSSS) capture within-person variability in state self-esteem over time? Whereas prior research found small correlations between the RSSS and temporal self-esteem instability (Kernis, Grannemann, & Barclay, 1989, 1992), we found moderate-to-large correlations. Our meta-analysis of these correlations showed convergent validity, and that studies with time-stamped state self-esteem assessments had higher correlations than those lacking them (Study 1). The RSSS also showed high test–retest reliability (Studies 2 & 3) and high convergent validity with the Labile Self-Esteem Scale (Dykman, 1998; Study 3). Exploratory analyses showed that the RSSS reflects short-term (daily, weekly) fluctuations in state self-esteem, but not long-term (annual) ones. We discuss the RSSS’ efficacy as an efficient state self-esteem instability measure.     

Using self-esteem to disaggregate psychopathy,narcissism, and aggression

Past research offers conflicting conclusions regarding the associations between self-esteem, psychopathy, narcissism, and aggression. The current study clarified these associations by examining self-esteem level and stability as it relates to the factors of psychopathy and narcissism predicting aggression. Self-report assessments were administered to 118 undergraduates. While self-esteem instability was not related to psychopathy or narcissism, it was positively correlated with aggression. Additionally, those with the healthier aspects of narcissism and Factor 1 features of psychopathy had high self-esteem and less aggression, while those with more pathological narcissism and Factor 2 features of psychopathy had lower self-esteem and more aggression. Specifically, the relationship between psychopathy Factor 1 and aggression was partially mediated by lower self-esteem.     

Structure of force variability during squats performed with an inertial flywheel device under stable versus unstable surfaces

The use of unstable surfaces during resistance training has demonstrated a maintenance or reduction on force production. However, the use of unstable surface on force variability has not been assessed using non-linear methods that may be better suited to detect changes in movement variability throughout a given movement. Consequently, this study compared the use of stable vs unstable surfaces on force variability during bilateral squats performed with an inertial flywheel device (Eccoteck, Byomedic System SCP, Spain). Twenty healthy men (mean ± SD: age 22.9 ± 2.9 years, height 1.81 ± 0.7 m, body mass 76.4 ± 7.6 kg and 1RM back squat 110.9 ± 19.7 kg) with a minimum of four years in resistance training performed six sets of six repetitions of squats at maximal concentric effort with one minute rest between sets. Force output on the vertical axes was measured using a strain gauge and the results were processed using non-linear sample entropy (SampEn). Results showed no differences for any of the dependent variables between stable and unstable conditions. SampEn showed no differences between conditions (chi-squared = 0.048 P = 0.827), while Force_mean and SampEn presented a small correlation (r = 0.184; p < 0.01). No changes in entropy were found over the course of the series. Together, these results suggest that the structure of force variability between stable and unstable surfaces are similar. This lack of difference between surfaces may be due to postural and anticipatory adjustments. Consequently, by introducing unstable surfaces to the flywheel bilateral squat exercise, practitioners may not observe changes in Force_mean and force variability when compared to stable surface training suggesting that increased training volumes or intensity may be required during unstable environments to cause a desired training stimulus.     

Psychological defense and self-esteem instability: Is defense style associated with unstable self-esteem?

Defense styles refer to the characteristic employment of automatic psychological processes to maintain and enhance self-esteem. On the basis of clinical literature pertaining to defense styles, it was hypothesized that the maturity of an individual’s defenses would be associated with fluctuations in one’s state self-esteem over time (i.e., self-esteem instability). To examine this hypothesis, the present study included daily diary measures that tracked the state self-esteem of 123 participants each day for 14 consecutive days. The results of the present study found that higher levels of immature defenses were associated with greater self-esteem instability. For both the intermediate and mature defense styles, their associations with self-esteem instability were moderated by self-esteem level such that higher levels of these defenses were associated with less self-esteem instability among those with low self-esteem.     

权力不稳定性对权力效应的逆转作用

摘 要 基于权力的趋近-抑制理论，本研究探讨权力不稳定性对权力效应产生逆转作用以及权力动机对这一逆转作用的影响。实验采用角色扮演法和真实任务角色来操纵被试的权力水平和权力不稳定性，以赌博任务中的冒险行为和金钱分配任务中的趋利行为来测量被试的权力趋近/抑制效应。结果发现：权力稳定条件下，高权力被试比低权力被试表现出更多的冒险行为和趋利行为；权力不稳定条件下则相反，低权力被试比高权力被试表现出更多的冒险行为和趋利行为。权力不稳定条件下高权力动机的高权力者相比低权力动机的高权力者倾向给自己分配更少的金额数，表现出更为明显的抑制倾向；而高权力动机的低权力者相比低权力动机的低权力者倾向于提出更高要求的金额数，表现出更为明显的趋近倾向。该研究证实了权力不稳定性对权力效应的逆转作用，而权力动机对这一逆转作用起到增强趋势。     

Paranoia and instability of self-esteem in adolescents

This study examined whether paranoid beliefs are associated with instability of self-esteem (SE) as hypothesized by Bentall et al. [Bentall, R. P., Corcoran, R., Howard, R., Blackwood, N., & Kinderman, P. (2001). Persecutory delusions: A review and theoretical integration. Clinical Psychology Review, 21, 1143–1192] in a community-based sample. Measures assessing SE, SE instability, paranoid ideation, and depressive symptoms were completed by 131 adolescents. A significant association between paranoia and SE instability was observed, even when taking into account global SE and depressive symptomatology. The results replicate previous findings, providing further evidence for a relationship between paranoid ideation and SE instability. Further, this study utilises a new measure of SE instability and explores the relationship between paranoia and SE within a hitherto unstudied age group using a multidimensional model of paranoia.