Childhood anxiety associated with low BMI in women with Anorexia Nervosa

Objective

Extremely low body mass index (BMI) values are associated with increased risk for death and poor long-term prognosis in individuals with anorexia nervosa (AN). The present study explores childhood personality characteristics that could be associated with the ability to attain an extremely low BMI.

Methods

Participants were 326 women from the Genetics of Anorexia Nervosa (GAN) Study who completed the Structured Interview for Anorexia Nervosa and Bulimic Syndromes and whose mother completed the Child Behavioral Checklist and/or Revised Dimensions of Temperament Survey.

Results

Children who were described as having greater fear or anxiety by their mothers attained lower BMIs during AN (p < 0.02). Path analysis in the GAN and a validation sample, Price Foundation Anorexia Nervosa Trios Study, confirmed the relation between early childhood anxiety, caloric restriction, qualitative food item restriction, excessive exercise, and low BMI. Path analysis also confirmed a relation between childhood anxiety and caloric restriction, which mediated the relation between childhood anxiety and low BMI in the GAN sample only.

Conclusion

Fearful or anxious behavior as a child was associated with the attainment of low BMI in AN and childhood anxiety was associated with caloric restriction. Measures of anxiety and factors associated with anxiety-proneness in childhood may index children at risk for restrictive behaviors and extremely low BMIs in AN.     

Feeling the Heat: Body Temperature and the Rate of Subjective Time, Revisited

Experiments investigating timing behaviour in humans under conditions where body temperature was raised or (much more rarely) lowered, dating from 1927 to 1993, were reviewed. These tested the hypothesis that humans possess a temperature-sensitive chemical or biological internal clock. Most studies used conditions in which subjects produced or estimated durations less than 100 sec long, probably using chronometric counting, but other experimental paradigms were sometimes employed. Data from each study were expressed in a uniform fashion, as plots of changes in the rate of subjective time (estimated from changes in timing behaviour) against changes in body temperature. In almost all cases, rate of subjective time increased when body temperature increased above normal, and decreased when body temperature was lowered below normal, although observations of the latter type were rare. The data also suggested a parametric effect of body temperature, with higher temperatures generally producing faster subjective time. Some possible mechanisms for the effects obtained were discussed, with the most promising explanation probably being that the temperature manipulation produces changes in arousal.     

Perinatal maternal undernutrition programs the offspring hypothalamo-pituitary-adrenal (HPA) axis

There is now compelling evidence, coming both from animal and human studies that an early exposure to undernutrition is frequently associated with low birth weight and programs HPA axis alterations throughout the lifespan. Although animal models have reported conflicting findings arising from differences in experimental paradigms and species, they have clearly demonstrated that such programming not only affects the brain but also the pituitary corticotrophs and the adrenal cortex. In fetuses, maternal undernutrition reduces HPA axis function and implicates a reduction of placental 11beta-HSD2 activity and a greater transplacental transfer of glucocorticoids (GRs). In young adults, usually only fine HPA axis alterations were observed, whereas in older ones, maternal undernutrition was frequently associated with chronic hyperactivity of this neuroendocrine axis. In humans, evidence of HPA axis dysregulation in people who were small at birth has recently emerged. Thus, we suggest that such alterations in adults may be implicated in the aetiology of several disorders related to the metabolic syndrome as well as to immune or inflammatory diseases. To reverse such programming, recent experimental reports have shown that postnatal environmental interventions, dietary modifications and the use of agents modulating the epigenomic state could partly restore physiological functions and thus open new therapeutic strategies.     

体像困扰与社会文化因素

数据显示大多数人对自己的体像不满意,而对体像的不满意可能形成困扰。存在体像困扰的个体更多体验抑郁、焦虑等负面情绪,且体像困扰和进食障碍、体像障碍等精神疾病均存在密切的关系。在介绍概念的同时,本文还对体像困扰相关社会文化因素的影响进行了综述。已有研究表明女性较男性更容易受到体像困扰的影响;体像困扰存在跨文化的一致性,也存在文化差异;家庭、同伴和媒体对于体像困扰均有影响。     

Are dietary restraint scales valid measures of acute dietary restriction? Unobtrusive observational data suggest not

The finding that dietary restraint scales predict onset of bulimic pathology has been interpreted as suggesting that dieting causes this eating disturbance, despite the dearth of evidence that these scales are valid measures of dietary restriction. The authors conducted 4 studies that tested whether dietary restraint scales were inversely correlated with unobtrusively measured caloric intake. These studies, which varied in foods consumed, settings, and populations, indicated that common dietary restraint scales were largely uncorrelated with acute caloric intake. Results suggest that these scales are not valid measures of short-term dietary restriction and imply that it may be prudent to reinterpret findings from studies thai use these scales, including those that suggest dietary restraint is a risk factor for bulimic pathology.     

Genetics of neuronal migration in the cerebral cortex

The development of the cerebral cortex requires large-scale movement of neurons from areas of proliferation to areas of differentiation and adult function in the cortex proper, and the patterns of this neuronal migration are surprisingly complex. The migration of neurons is affected by several naturally occurring genetic defects in humans and mice; identification of the genes responsible for some of these conditions has recently yielded new insights into the mechanisms that regulate migration. Other key genes have been identified via the creation of induced mutations that can also cause dramatic disorders of neuronal migration. However, our understanding of the physiological and biochemical links between these genes is still relatively spotty. A number of molecules have also been studied in mice (Reelin, mDab1, and the VLDL and ApoE2 receptors) that appear to represent part of a coherent signaling pathway that regulates migration, because multiple genes cause an indistinguishable phenotype when mutated. On the other hand, two human genes that cause lissencephaly (LIS1, DCX) encode proteins that have recently been implicated as regulators or microtubule dynamics. This article reviews some of the mutant phenotypes in light of the mechanisms of neuronal migration. MRDD Research Reviews 6:34-40, 2000.     

Effects of cold on human information processing: Application of a reaction time paradigm

Only a very few studies on the effects of cold on human information processing appear to exist. Therefore, the present experiment was designed to study the effects of the experimentally induced lowering of body core temperature on information processing, while applying a reaction time paradigm. Thirty healthy male volunteers performed a stimulus evaluation—response selection reaction time task after exposure to ambient temperatures of either 28 or 5°C. A 0.5°C-decrease in body core temperature resulted in a significant increase in both reaction and movement time indicating a general deteriorating effect of lowering of body core temperature on information processing. Mean reaction times were 538 ms and 549 ms for the control and the cold group, respectively (p<.05). The respective mean movement times were 298 ms and 269 ms (p<.001). Speed of stimulus evaluation was not sensitive to decreases in body core temperature. However, response complexity and body core temperature showed a significant interaction in their effect on movement time (p<.05), indicating that lowering of body core temperature is more likely to affect response-related stages of central information processing rather than stimulus evaluation. Furthermore, movement time appeared to be more sensitive to cold-induced effects on information processing as compared to reaction time. Additional correlational analyses suggest that the observed effects can be considered as independent of changes in skin temperature and experienced levels of thermal discomfort. Taken together, the results indicate that lowering of body core temperature differentially affects various stages of information processing.     

Lessons learned in deep brain stimulation for movement and neuropsychiatric disorders

The introduction of deep brain stimulation (DBS) as a treatment for medication-refractory essential tremor in the late 1980s revealed, for the first time, that "chronically" implanted brain hardware had the potential to modulate neurologic function with surprisingly low morbidity. Over time, the therapeutic promise of DBS has become evident in Parkinson's disease and dystonia. In some experienced centers, complex tremor disorders, such as posttraumatic Holmes tremor and the tremor of multiple sclerosis, are being increasingly targeted. More recently, other indications, including obsessive-compulsive disorder, Tourette's syndrome, major depression, and chronic pain, have been proposed. As the field has expanded, our knowledge about potential cognitive side effects of DBS has also expanded. This article reviews the current knowledge regarding the impact of stimulation of the subthalamic nucleus, globus pallidus internus, and ventralis intermedius nucleus of the thalamus on symptoms in essential tremor, Parkinson's disease, and dystonia. Also discussed are the emerging targets, what is known about the cognitive sequelae of DBS, and what has been learned about the complications and therapeutic failures.     

Left caloric vestibular stimulation as a tool to reveal implicit and explicit parameters of body representation

Homeostatic parameters, such as temperature, are related to body representation. In this study, we measured whether caloric vestibular stimulation (CVS) alters body temperature and tactile processing, and if in the direction predicted by a holistic body matrix representation.Skin temperature and tactile two-point discrimination (TPD) acuity were measured for both arms before, immediately after and with a delay from CVS. Participants were also administered a personality questionnaire and an anxiety inventory to rule out confounding factors. Two control experiments were planned to exclude casual variations.Our results show that temperature drops significantly in both arms after CVS. CVS also induces a bilateral improvement in tactile acuity (even though not immediately after but in the delayed condition). Finally, these effects are not due to learning, as demonstrated by the control experiment.In summary, our results suggest that vestibular stimulation updates body representation, supporting the evidence in favor of a body matrix.     

Capitalizing on cortical plasticity: influence of physical activity on cognition and brain function

Given the aging populations in many countries throughout the world, there is an increasing interest in lifestyle factors and interventions that will enhance the cognitive vitality of older adults and reduce the risk for age-related neurological disorders, such as Alzheimer's disease. In this review, we evaluate the hypothesis that physical activity and exercise might serve to protect, and also enhance, cognitive and brain function across the adult lifespan. To this end, we critically review three separate literatures that have examined the influence of physical activity and exercise on cognition, brain function and brain structure of adults, including epidemiological or prospective observational studies, randomized human clinical interventions and non-human animal studies. We suggest that this literature supports the claim that physical activity enhances cognitive and brain function, and protects against the development of neurodegenerative diseases. We discuss future directions to address currently unresolved questions, such as interactions between multiple lifestyle factors on offsetting or protecting against cognitive and neural decline, and conclude that physical activity is an inexpensive treatment that could have substantial preventative and restorative properties for cognitive and brain function.     

Chronic stress modulates the use of spatial and stimulus-response learning strategies in mice and man

Acute stress modulates multiple memory systems in favor of caudate nucleus-dependent stimulus-response and at the expense of hippocampus-dependent spatial learning and memory. We examined in mice and humans whether chronic stress has similar consequences. Male C57BL/6J mice that had been repeatedly exposed to rats ("rat stress") used in a circular hole board task significantly more often a stimulus-response strategy (33%) than control mice (0%). While velocity was increased, differences in latency to exit hole, distance moved or number of holes visited were not observed. Increased velocity and performance during retention trials one day later indicates altered emotionality and motivation to explore in rat stressed mice. Forty healthy young men and women were split into "high chronic stress" and "low chronic stress" groups based on their answers in a chronic stress questionnaire ("Trier Inventory of Chronic Stress"-TICS) and trained in a 2D task. A test trial immediately after training revealed that participants of the "high chronic stress" group used the S-R strategy significantly more often (94%) than participants of the "low chronic stress" group (52%). Verbal self-reports confirmed the strategy derived from participants' choice in the test trial. Learning performance was unaffected by the chronic stress level. We conclude that one consequence of chronic stress is the shift to more rigid stimulus-response learning, that is accompanied by changes in motivational factors in mice.     

Dopamin-Dysregulations-Syndrom bei Morbus Parkinson

Parkinson’s disease is a neurodegenerative disease with the cardinal symptoms bradykinesia, rigidity and tremor. In 1817, James Parkinson already described in his "Essay on the Shaking Palsy" in addition to the motor symptoms also autonomic, cognitive and behavioral disturbances (Parkinson, An essay on the shaking palsy. Sherwood, Nealy and Jones, London, 1817). Their impact on quality of life has been underestimated until more recent times. Dopamine dysregulation syndrome is an iatrogenic disturbance, characterized by an addictive pattern of dopamine replacement therapy use. Despite good control of motor symptoms, patients often increase doses of dopamine replacement therapy in excess of those normally required. Consequently these behavioral disorders may also result in social and professional problems.     

Episodic-like memory in zebrafish

Episodic-like memory tests often aid in determining an animal’s ability to recall the what, where, and which (context) of an event. To date, this type of memory has been demonstrated in humans, wild chacma baboons, corvids (Scrub jays), humming birds, mice, rats, Yucatan minipigs, and cuttlefish. The potential for this type of memory in zebrafish remains unexplored even though they are quickly becoming an essential model organism for the study of a variety of human cognitive and mental disorders. Here we explore the episodic-like capabilities of zebrafish (Danio rerio) in a previously established mammalian memory paradigm. We demonstrate that when zebrafish were presented with a familiar object in a familiar context but a novel location within that context, they spend more time in the novel quadrant. Thus, zebrafish display episodic-like memory as they remember what object they saw, where they saw it (quadrant location), and on which occasion (yellow or blue walls) it was presented.     

Chronic social stress during adolescence in mice alters fat distribution in late life: prevention by antidepressant treatment

Obesity and visceral fat accumulation are key features of the metabolic syndrome that represents one of the main health problems in western societies due to its neurovascular and cardiovascular complications. Epidemiological studies have identified chronic stress exposure as an important risk factor for the development of obesity and metabolic syndrome, but also psychiatric diseases, especially affective disorders. However, it is still unclear if chronic stress has merely transient or potentially lasting effects on body composition. Here, we investigated the effects of chronic social stress during the adolescent period on body fat composition in mice one year after the cessation of the stressor. We found that stress exposure during the adolescent period decreases subcutaneous fat content, without change in visceral fat, and consequently increases the visceral fat/subcutaneous fat ratio in adulthood. Further, we demonstrated that treatment with a selective serotonin reuptake inhibitor (paroxetine) during stress exposure prevented later effects on body fat distribution. These results from a recently validated chronic stress paradigm in mice provide evidence that stressful experiences during adolescence can alter body fat distribution in adulthood, thereby possibly contributing to an increased risk for metabolic diseases. Antidepressant treatment disrupted this effect underlining the link between the stress hormone system, metabolic homeostasis and affective disorders.     

APP23 mice as a model of Alzheimer's disease: an example of a transgenic approach to modeling a CNS disorder

Animal models are considered essential in research ensuing elucidation of human disease processes and subsequently, testing of potential therapeutic strategies. This is especially true for neurodegenerative disorders, in which the first steps in pathogenesis are often not accessible in human patients. Alzheimer's disease is vastly becoming a major medical and socioeconomic problem in our aging society. Valid animal models for this uniquely human condition should exhibit histopathological, biochemical, cognitive, and behavioral alterations observed in Alzheimer's disease patients. Major progress has been made since the understanding of the genetic basis of Alzheimer's disease and the development and improvement of transgenic mouse models. All present Alzheimer's disease models developed are partial but nevertheless essential in further unraveling the nature and spatial and temporal development of the complex molecular pathology underlying this condition. One of the more recent transgenic attempts to model Alzheimer's disease is the APP23 transgenic mouse. This article describes the development and assessment of this human amyloid precursor protein overexpression model. We summarize histopathological and biochemical, cognitive and behavioral observations made in heterozygous APP23 mice, thereby emphasizing the model's contribution to clarification of neurodegenerative disease mechanisms. In addition, the first therapeutic interventions in the APP23 model are included.     

Eating Disorders in Men: Current Considerations

Over the past two decades, there has been a change in the way men think about their bodies. The media portrays images of men with muscular bodies and a six pack abdomen. These images can create body dissatisfaction in males. With the change in the way that the media and society in the United States look at men, so has the drive for men to achieve this ideal body image. Eating disorders, body dysmorphia, and strict exercise and diet regimens seem to plague young men as do the images in advertisements. Although eating disorders in men are similar to what women experience, men seem to strive for more body mass whereas women try to obtain thinness. Gay men and heterosexual men seem to experience eating disorders in the same way although there are differences between how they perceive their bodies. This paper outlines how the media contributes to body dissatisfaction in men. In addition to understanding how the media affects men, it is important to review and possibly revise out understanding of eating disorders and body dysmorphia symptoms to gain a solid understanding of how these symptoms appear in men today.     

A Lifespan Perspective on Dependency and Self-Criticism: Age-Related Differences from 18 to 59

A sizeable body of research suggests that self-definition and relatedness represent two fundamental developmental streams across the lifespan (Blatt in Psychoanal Study Child 29:107–157, 1974; Blatt and Luyten in Dev Psychopathol 21:793–814, 2009). Adverse developmental experiences have been found to affect personality development leading to high levels of self-criticism or dependency. No research to date has examined the developmental trends of these factors across the lifespan or the moderating impact of important life experiences. In a sample of 3,586 Canadians aged 18–59, age-related differences in self-criticism and dependency were examined. Analyses were replicated in a multicultural sample of 612 Canadians and 647 individuals born and currently living on the continent of Asia. Controlling for both neuroticism and depressive symptoms, results showed that self-criticism and dependency decreased linearly across the lifespan in both samples and across cultures; however, the decrease in self-criticism was steeper for men compared to women, while the decrease in dependency was steeper for those without children compared to those with children. Furthermore, participants who were in a romantic relationship showed lower levels of self-criticism and higher levels of dependency compared to those who were not in a romantic relationship. Results suggest that people may develop a healthier view of close relationships with others and acquire more positive self-views over the course of their lives.     

5-羟色胺基因缺陷增强急性应激后高唤醒状态

剧烈的应激刺激会引起持续的高唤醒状态, 是多种应激障碍的核心症状, 并推进其他症状的发生发展。本研究关注5-羟色胺在应激诱发高唤醒的发生、发展中的作用, 通过测量听觉惊吓反射水平反映高唤醒状态, 考察色氨酸羟化酶-2基因缺陷小鼠在天敌或电击应激前后高唤醒的变化。研究发现, 雄性基因缺陷小鼠在应激后出现持续一周以上的高唤醒表现, 而野生型小鼠高唤醒状态很快恢复。结果提示, 基因缺陷引起的5-羟色胺降低可能是强应激诱发的持续高唤醒的易感因素。     

Serotonin enhances the impact of health information on food choice

Serotonin has been implicated in promoting self-control, regulation of hunger and physiological homeostasis, and regulation of caloric intake. However, it remains unclear whether the effects of serotonin on caloric intake reflect purely homeostatic mechanisms, or whether serotonin also modulates cognitive processes involved in dietary decision making. We investigated the effects of an acute dose of the serotonin reuptake inhibitor citalopram on choices between food items that differed along taste and health attributes, compared with placebo and the noradrenaline reuptake inhibitor atomoxetine. Twenty-seven participants attended three sessions and received single doses of atomoxetine, citalopram, and placebo in a double-blind randomised cross-over design. Relative to placebo, citalopram increased choices of more healthy foods over less healthy foods. Citalopram also increased the emphasis on health considerations in decisions. Atomoxetine did not affect decision making relative to placebo. The results support the hypothesis that serotonin may influence food choice by enhancing a focus on long-term goals. The findings are relevant for understanding decisions about food consumption and also for treating health conditions such as eating disorders and obesity.