Lateralization and stress responses in mice: Interindividual differences in the association of brain,neuroendocrine, and immune responses

Behavioral lateralization, as assessed by paw preference in a food-reaching task in mice, is associated with brain metabolism asymmetries and immune reactivity as well as neuroendocrine and immune stress responses. Therefore, each individual may be characterized by a lateralization score in association with a particular pattern of immune and neuroendocrine reactivities. These interindividual differences may be responsible for the variability among members of a population in the responses to various insults including psychological stressors and infections.     

Parental hand preference and manual functional asymmetry in preschool children

Hand preference and hand skill in 1150 normal children between 3 and 6 years of age and hand preference of their parents were assessed to study the effect of parental hand preference on different dimensionsl of manual asymmetry in children. Children hand skill was measured with a computerized version of the Peg Moving Task which allowed us to split the overall performance into two components, a “transport time” and a “search time.” Paternal and maternal left-handedness was significantly related to child left-handedness. Both components of hand skill asymmetry were reduced with mother's left-handedness and one component (search time) with father's left-handedness. A significant impact of parental hand preference on child hand skill asymmetry, after controlling for child hand preference, was observed. When this analysis was limited to strong right-handed children, a greater paternal effect on child hand skill emerged. These results show the usefulness of performance tasks in detecting parent-child associations concerning manual functional asymmetry.     

Genes, Evolution, and Personality

There is abundant evidence, some of it reviewed in this paper, that personality traits are substantially influenced by the genes. Much remains to be understood about how and why this is the case. We argue that placing the behavior genetics of personality in the context of epidemiology, evolutionary psychology, and neighboring psychological domains such as interests and attitudes should help lead to new insights. We suggest that important methodological advances, such as measuring traits from multiple viewpoints, using large samples, and analyzing data by modern multivariate techniques, have already led to major changes in our view of such perennial puzzles as the role of unshared environment in personality. In the long run, but not yet, approaches via molecular genetics and brain physiology may also make decisive contributions to understanding the heritability of personality traits. We conclude that the behavior genetics of personality is alive and flourishing but that there remains ample scope for new growth and that much social science research is seriously compromised if it does not incorporate genetic variation in its explanatory models.     

The role of cortisol reactivity in children's and adults' memory of a prior stressful experience

The purpose of this study was to identify whether cortisol reactivity to a stressful laboratory event was related to children's memory of that event and to determine whether this relation was comparable to that observed in adults. Nine- to 12-year-olds and young adults completed an impromptu speech and math task during which repeated cortisol samples and self-reported stress ratings were collected. Two weeks later, participants' memory for the tasks was examined. Greater cortisol reactivity was associated with enhanced memory, most prominently in children. Self-reported stress was unrelated to memory. Findings reveal that an important mechanism underlying the association between emotion and memory in adults, namely activation of the hypothalamic pituitary adrenal axis, appears to operate similarly in late childhood. Findings also demonstrate that positive associations between cortisol reactivity and memory are evident when the event that actually elicited that reactivity serves as the to-be-remembered event.     

Speech rate,loudness, and cardiovascular reactivity

This paper reports the results of two studies that investigated the relationship between speech rate, loudness, and cardiovascular reactivity (CVR). One study involved the separate manipulation of speech rate and loudness and assessed its effects on CVR during a routine reading task. The second study involved the simultaneous manipulation of both loudness and speech rate and studied its effects on CVR within the context of a personal interview. In both studies, the reduction of speech rate and/or loudness was associated with a significant reduction in CVR. On the other hand, increasing speech rate and/or loudness had no, or only a very minimal, effect on CVR. It is suggested that in the absence of emotional arousal, especially anger-arousal, rapid and loud speech per se is not associated with significant cardiovascular hyperreactivity. On the other hand, our findings suggest that training people to speak slowly and softly may be an effective approach for the control of cardiovascular hyperreactivity.     

Psychopathy, startle blink modulation, and electrodermal reactivity in twin men

Psychopathy is a personality disorder with interpersonal-emotional and antisocial deviance facets. This study investigated these facets of psychopathy prospectively using normal-range personality traits in a community sample of young adult men who completed a picture-viewing task that included startle blink and skin conductance measures, like tasks used to study psychopathy in incarcerated men. Consistent with prior research, scores on the interpersonal-emotional facet of psychopathy ("fearless dominance") were associated with deficient fear-potentiated startle. Conversely, scores on the social deviance facet of psychopathy ("impulsive antisociality") were associated with smaller overall skin conductance magnitudes. Participants high in fearless dominance also exhibited deficient skin conductance magnitudes specifically to aversive pictures. Findings encourage further investigation of psychopathy and its etiology in community samples.     

Early parenting predicts hippocampal subregion volume via stress reactivity in childhood

Rodent models indicate that parenting shapes offspring outcomes by programming the hypothalamic–pituitary–adrenal axis response to stress and, ultimately, altering brain structure and function. The present study tested this hypothesis and explored possible timing-dependent associations in a longitudinal sample of children (N = 63). At Time 1 (M = 4.23 ± 0.84 years) and Time 2 (M = 7.20 ± 0.89 years), children completed parent–child interaction tasks and a laboratory stressor after which salivary cortisol samples were collected. At Time 2, children also completed a structural MRI. Analyses revealed timing- and region-dependent associations between early and concurrent parenting and cortisol reactivity and hippocampal subregion volumes. Moreover, greater negative parenting during early childhood predicted greater cortisol reactivity three years later, which, in turn, led to reduced left hippocampal tail volume. Findings suggest that the hippocampus is sensitive to environmental influences during early childhood, a result that parallels findings from rodent models.     

应对方式、人格特征与应激水平的关系

目的：研究应对方式、人格特征与应激水平的相互关系。方法：对某企业集团中不同职业群体的4745名职工采用特质应对量表(TCSQ)、大五人格问卷(NEO-FFl)和自制的社会应激事件凋查表进行调查。结果：男性、20～30岁组、文化程度高的被试，其消极应对(NC)和积极应对(PC)高，应激水平高。NC与人格中的神经质(N)显著正相关，与外倾性(E)和严谨性(C)显著负相关；PC与N呈显著负相关，与E、C、宜人性(A)显著正相关逐步回归分析表明，影响应激水平的因素依次为NC、N、C、E、PC、A。结论：人格特征、应对方式与应激水平呈显著相关。性别、年龄、文化程度的差异对应对方式有一定影响。     

Components of sensorimotor adaptation in young and elderly subjects

Previous studies have found that sensorimotor adaptation to visual distortions is degraded in seniors compared with younger subjects, whereas after-effects on removal of the distortion are age-independent. The latter finding was interpreted as evidence that adaptive recalibration is not affected by old age, and that the observed degradation is therefore due to impairment of strategic control. However, after-effects are not a reliable measure of recalibration, because they can be artificially inflated by perseveration, a characteristic symptom in old age. The present work therefore introduces a test of recalibration which is insensitive to perseveration. Twelve young and twelve old subjects executed center-out pointing movements while visual feedback about their fingertip was either veridical (baseline), 60-deg rotated (adaptation), or absent (after-effect).They also executed tracking movements toward an unpredictably moving object before and after the pointing task. Seniors adapted less than younger subjects but their after-effects were not degraded. More importantly, transfer of adaptation from a pointing to a tracking task was not degraded in seniors. The latter outcome documents, in a more compelling fashion than previous work, that recalibration in the elderly is not impaired, and that the observed deficit of adaptation is therefore most probably because of impaired strategic control. This conclusion is supported by two additional findings: compared with young subjects our seniors performed less well on a cognitive screening test and acquired no explicit knowledge about the nature of the imposed visual distortion.     

缓解期重性抑郁与心境恶劣患者人格特征及人格障碍研究

目的：研究重性抑郁症(MDD)和心境恶劣障碍(DD)患者在人格维度、人格特质水平及人格模型及人格障碍倾向性方面的特征。方法：采用NEO-PI-R个性调查表及人格诊断问卷(PDQ^ 4)对58例MDD和57例DD患者及115例正常人进行测试。结果：MDD和DD在NEO-PI-R的五因素人格模型的外向性、严谨性得分均低于正常组，DD患者的神经质分高于MDD患者，MDD患者的顺同性分高于正常组；在30个特质层面上，MDD和DD与正常组之间有显著性差异，DD患者的N1(焦虑)、N4(自我意识)分明显高于MDD患者，E4(热情性)、A1(信任感)分明显低于MDD患者；MDD和DD在PDQ^ 4的边缘型(BDL)、回避型(AVD)、抑郁型(DEP)、分裂性(SZD)、偏执型(PND)、强迫型(OBC)人格障碍得分明显高于正常组，DD患者在分裂型得分明显高于MDD患者，在表演型(HST)分明显高于正常组。结论：MDD和DD的人格特征既有共同的之处，也存在差异。两者均伴有人格障碍，但DD患者比MDD患者人格障碍更明显。     

研究生人格倾向与人格障碍的关系

目的 探讨人格倾向与人格障碍的关系.方法 应用人格类型量表(MBTI)和人格诊断问卷(PDQ-4 ),对某师范大学180名研究生进行施测.结果 MBTI与PDQ-4 的相关矩阵中,呈显著正相关的有P因子与反社会型,F因子与边缘型、回避型、依赖型,N因子与表演型、分裂型、反社会型和被动攻击型,S因子与依赖型,I因子与分裂性、分裂型、回避型、依赖型、强迫型和抑郁型,E因子与表演型.结论 人格类型的某些因子与某些人格障碍倾向之间存在着一定的相关.     

Mechanisms underlying hemodynamic and neuroendocrine stress reactivity at different phases of the menstrual cycle

This study examined the association of menstrual cycle phase with stress reactivity as well as the hormonal and neuroendocrine mechanisms contributing to cycle effects. Fifty‐seven women underwent a modified Trier Social Stress Test during the early follicular, late follicular, and luteal phases of the menstrual cycle. Greater increases in cardiac index (CI) and greater decreases in vascular resistance index (VRI) during speech were observed in the luteal phase relative to other phases, while greater increases in epinephrine (EPI) was observed during the late follicular and luteal phases compared to the early follicular phase. Luteal phase estradiol predicted luteal EPI reactivity but not CI or VRI reactivity, while luteal phase EPI reactivity predicted luteal phase CI and VRI reactivity. Thus, cycle‐related changes in EPI reactivity may be a stronger determinant of cycle effects on hemodynamic reactivity than sex hormones per se.     

人格特质和社会支持与心理健康的关系模型

目的：考察社会支持与心理健康的关系以及构建人格和社会支持与心理健康的关系模型。方法：采用横向与纵向研究相结合的方式对192名大学生进行了问卷调查。结果：社会支持对心理健康有显著的主效应．社会支持主要是通过同期心理健康以及后期社会支持两种方式对后期心理健康产生影响；人格不仅可直接预测心理健康状况，而且也是社会支持与心理健康的中介变量。结论：社会支持主要是通过人格对心理健康产生间接影响。社会支持可以有效预测两年后的心理健康状况。     

Adiposity, leptin and stress reactivity in humans

Evidence suggests that individuals who are more obese may be more responsive to stress. Stress activates the sympathetic nervous system (SNS) and the adipose-tissue cytokine leptin stimulates SNS activity in animals. We examined the relationship between adiposity, leptin and physiological responses to acute laboratory stress in 67 women. We predicted that individuals with greater adiposity and/or higher plasma leptin would be more stress-responsive. Adiposity was unrelated to cardiovascular or neuroendocrine stress reactivity. However, women with larger waists had greater stress-induced increases in plasma leptin and interleukin-1 receptor antagonist (IL-1Ra). Similarly, women with higher basal leptin displayed greater stress-induced increases in heart rate and plasma interleukin-6, and larger decreases in heart rate variability and cardiac pre-ejection period. Heightened cardiovascular and inflammatory stress responses are predictive of future cardiovascular risk. Our findings suggest that the cytokines leptin and IL-1Ra may play a role in the association between obesity, stress and cardiovascular health.     

Sexual and olfactory preference in noncopulating male rats

In some species including rats, mice, gerbils, and rams, apparently normal males fail to copulate when repeatedly tested with receptive females. These animals are called "noncopulators (NC)," and the cause of this behavioral deficit is unknown. It has been shown that NC rats do not have hormonal alterations or deficits in the mechanisms that control penile function. The present study was designed to examine (Experiment 1) whether NC male rats prefer receptive females to sexually active males. In addition, the olfactory preference for bedding soiled from estrous or for anestrous bedding was investigated. These tests were performed in NC and copulating (C) male rats when the subjects were intact, gonadectomized (GDX), or GDX and treated with high doses of testosterone propionate (TP). Our results demonstrate that NC rats do not display sexual behavior even after high TP treatment. While C male rats have a clear preference for receptive females as opposed to a sexually active male, NC rats do not. In all hormonal conditions, the preference shown by NC rats for estrous bedding was significantly reduced in comparison to that seen in C rats. TP treatment in NC rats did not modify either partner or odor preference. In Experiment 2, we evaluated if NC rats are feminized and if it could be easier to induce feminine-like behavior by hormone treatment with estradiol benzoate (EB) or with EB plus progesterone (P) (EB+P). Odor preference for estrous or male bedding under these hormonal conditions was also compared. No differences between NC and C rats were found in feminine sexual behavior. In the olfactory test, we found that NC rats prefer odors from receptive females as opposed to male odors, but this preference is reduced compared to that of C rats. Males treated with EB or EB+P show no preference for female odors. These results demonstrate that treatment with EB or EB+P does not increase feminine sexual behavior in NC rats.     

Studies of the effects of inhaled magnesium on airway reactivity to histamine and adenosine monophosphate in asthmatic subjects

Background Magnesium is a cation with smooth muscle relaxant and anti-inflammatory effects and may therefore have a role in the therapy of asthma. Several studies have investigated the effects of intravenous magnesium in acute or stable asthma, but little is known about the effects of inhaled magnesium. Objective To measure the effects of a single inhaled nebulized dose of 180 mg magnesium sulphate on airway reactivity to a direct-acting bronchoconstrictor (histamine) and an indirect-acting bronchoconstrictor (adenosine monophosphate [AMP]) in asthmatic subjects. Objective Two separate randomized, double-blind, placebo-controlled crossover studies, each involving 10 asthmatic subjects. In the histamine study, airway reactivity to histamine was measured and lung function allowed to recover spontaneously over 50 min before administering nebulized magnesium sulphate or saline placebo. Airway reactivity to histamine was then measured at 5 and 50 min. In the AMP study, a single measurement of airway reactivity was made 5 min after magnesium or placebo. Results In the histamine study, the provocative dose required to reduce FEV₁ by 20% (PD₂₀FEV₁) was significantly lower after magnesium than after placebo, by a mean (95% CI) of 1.02 (0.22–1.82) doubling doses at 5 min (P= 0.018), and 1.0 (0.3–1.7) doubling doses at 50 min (P= 0.01). In the AMP study, PD₂₀FEV₁ was also significantly lower at 5 min after magnesium than after saline, by 0.64 (0.12–1.16) doubling doses (P= 0.023), though this difference was not statistically significant after adjustment for differences in baseline FEV₁ on the two study days. Conclusions Inhaled magnesium did not protect against the effects of these direct and indirect bronchoconstrictor stimuli in subjects with asthma, and may have increased airway reactivity to histamine.