从端粒和端粒酶探析冥想对压力的缓解作用

冥想是一种维持自我注意的身心调节技术,是缓解因压力所致的抑郁、焦虑等消极情绪的有效方法。端粒是维持染色体稳定和完整的DNA片段,大量有关冥想对端粒及端粒酶活性影响的研究阐明,通常情况下压力人群经过冥想训练能提高端粒长度并增加端粒酶活性,这种改变与压力缓解密切相关。这一积极效果主要得益于皮质醇和炎症等生物因素及心理和环境等非生物因素。未来可以通过对比不同冥想练习的效果、增加追踪研究、多学科联合及扩大样本等找到最有利于提高端粒长度和端粒酶活性的冥想方式。     

人类平均寿命的发展趋势及对策

端粒是真核生物染色体末端由许多简单重复序列和相关蛋白组成的复合结构,具有维持染色体结构完整性的作用。端粒有随着细胞分裂次数增加而逐渐减少的趋势。端粒酶是一种逆转录酶,以以自身ＲＮＡ为模板,合成端粒重复序列,加对新合成ＤＮＡ链末端,以维持染色体端粒长度的稳定性。     

冥想的安全性

大量研究表明冥想有助于身心健康的维持与幸福感的提升, 但与此同时, 飞速发展的研究与实践却严重忽略了对其安全性的考察。目前, 我们对冥想各群体(临床人群、修行人、正念冥想指导者、普通练习者及大学生等)不良反应的表现、影响因素及发生与转化机制等都知之甚少, 目前国内该领域的研究尚属空白, 这是迫切需要研究者和实践者重视和严肃对待的伦理问题。国外研究表明, 总体而言, 冥想不良反应率为8.3%, 表现在认知、感知觉、情感、躯体化、意志、自我意识与社会功能等7方面内容的不适或改变, 严重的甚至出现自杀意念与行为; 冥想不良反应的影响因素包括练习者、练习、关系及健康行为等4方面的内容。中国文化下本土化研究的开展以及冥想指导者胜任力等问题是未来研究的重要方向, 分解设计、纵向设计与个人中心取向是重要的研究方法。     

端粒酶的调控在肿瘤治疗中的启示

1　端粒酶与肿瘤的关系早在 1990年 ,人们就注意到端粒酶与肿瘤的关系。在人体内 ,正常的体细胞因缺乏端粒酶活性 ,随着细胞的分裂 ,端粒持续丢失 ,直到细胞死亡。而在具有永生性的细胞株中 ,存在着极高的端粒酶活性 ,端粒酶对端粒的不断合成 ,使端粒的长度保持稳定 ,细胞获得无限的增殖能力 ,进而发展成为肿瘤。自 1994年Ｃｈｒｉｓｔｏｐｈｅｒ等人发现 ,体外癌细胞株及人体的卵巢癌都有端粒酶活性的高表达以来 ,迄今已积累了较多的资料。目前的研究资料表明 ,端粒酶几乎在人类恶性肿瘤中均有不同程度的高表达 ,其活性的检出率为 85%～ 95…     

冥想对注意能力的影响

所有冥想方法都要对注意进行管理, 注意是冥想的核心机制。近期研究发现, 冥想显著提高了持续性注意、执行注意和选择性注意分配等多种注意能力。认知神经科学研究发现, 冥想使注意资源分配更有效; 长期冥想者表现出更高的失匹配负波波幅和更低的β波幅; 冥想增强了中央执行网络有关脑区的功能联结, 提高了突出网络有关脑区的活动; 注意聚焦冥想降低了默认网络有关脑区的活动。另外, 作为一种提高注意能力的方法, 冥想不仅适用于注意缺陷多动障碍患者和已康复的抑郁症患者等有注意相关障碍的临床群体, 也适用于儿童和老年人等多种年龄阶段的健康群体。未来应通过追踪研究探讨冥想的长期效果; 探索冥想中注意与情绪的交互作用; 根据群体特征设计出更有针对性的冥想。     

基于心理学视域的冥想研究

冥想(meditation)是一些综合性的心理和行为训练, 它有助于个体建立一种特殊的注意机制, 达到心理上的整体提升。心理学目前对冥想的研究主要集中在冥想的脑机制及冥想的功能(心理恢复、心理发展)两个方面, 常使用的研究工具主要有量表和EEG、fMRI、SPECT等仪器设备。未来的冥想研究应该在进一步规范冥想训练技术的基础上, 侧重于各种冥想技术的比较并对冥想结果开展长期的跟踪研究。     

正念冥想训练水平对情绪加工的影响

越来越多的研究表明,正念冥想训练影响情绪加工。本文从正念冥想训练水平（包括临时训练、短时训练和长期训练）角度出发,系统回顾了不同水平的正念冥想训练对情绪加工的调节效应。综述发现,不同水平正念冥想训练都能够提高个体情绪调节能力,临时正念冥想训练作为一种有效的情绪调节方法影响情绪加工,而短期正念冥想训练和长期禅修训练通过增加个体正念意识,增强个体情绪接受力影响情绪加工。未来的研究需进一步在区分正念冥想训练时间和正念冥想训练类别基础上,探讨正念冥想训练影响情绪加工的认知神经机制。     

开放监控冥想的特定影响效果

近几年来,开放监控冥想(Open Monitoring Meditation,OM)受到越来越多的关注,许多研究者对它进行了系统研究。与其它冥想,特别是与聚焦注意冥想(Focus Attention Meditation,FA)相比较,OM具有明显的差异。OM似乎对某些认知过程(创造性思维)的影响以及疼痛和焦虑的缓解具有优势,而对注意力的影响结果并不一致。脑电波、功能定位以及脑功能关联性方面的研究结果初步揭示了开放监控冥想过程中的脑神经机制,但是这种冥想对于默认网络的影响效果表现出不一致性。另外,研究中使用的OM训练方法也存在明显的差异性,尤其是注意的起点是否从呼吸开始,以及是否需要保持注意两个方面。这些结果需要今后的研究使用更加标准化的方法进一步明确。     

冥想使人变得平和——人们对正、负性情绪图片的情绪反应可因冥想训练而降低

虽然前人已有不少研究发现冥想具有减少个体焦虑、缓解抑郁水平等功能,并且也已经揭示了冥想促进情绪调节能力的认知神经科学机理,但对于冥想会怎样调制人们对于外部施加的正、负性情绪刺激(图片)的情绪反应尚不清楚,冥想究竟会使人们对外部施加的情绪刺激的敏感性增强还是减弱?如果冥想能够调节和缓解人们的情绪反应的话,那么,这种调节作用是“双向的”(即对正性或负性情绪刺激能产生具有不同效价方向的调节作用)还是“单向的”(即对正性或负性情绪刺激产生具有相同效价方向的调节作用)?为了检验和回答上述问题,本研究以无冥想(或相关)经验的大学生为被试,通过随机实验组、控制组前后测的实验设计,考察了冥想训练能否影响被试对于正、负性情绪图片的情绪唤起.62名大学生被试被随机分配到实验组和控制组(每组31人),实验组参与连续5天、每天20 min的冥想练习,控制组在此期间的控制任务为通常的闭眼休息.结果显示:冥想组在练习过程中的脑α波指数显著升高;与控制组相比,冥想组被试对消极图片的效价评定值显著改善,这表明冥想降低了被试对负性情绪图片的情绪反应,研究还发现了冥想降低被试对正性情绪图片的积极评价倾向,从而证明对外部施加的正、负性情绪刺激而言,冥想训练的调制作用是使人们的情绪反应趋于平和.     

经验性回避对抑郁症发病的影响及慈心冥想干预方法的研究

经验性回避和反刍思维导致了抑郁症的发病和症状的持续,并且抑郁症的反刍思维与认知行为的回避倾向有非常密切的联系.以正念为基础的干预方法是当代心理学研究的一个热点,而与其密切相关的慈心冥想则很少被讨论.慈心冥想是指发展出对人的一种无条件、积极的慈爱与宽容的情感.正念能够增加对此时此刻的觉察,慈心冥想能够增加积极情感、降低消极情感,两者恰恰能够针对性地应对回避行为和反刍思维,从而减轻抑郁的症状.慈心冥想和正念冥想相结合,能为抑郁症提供更为有效的治疗.     

Telomeres in a Life-Span Perspective: A New "Psychobiomarker"?

ABSTRACT— In order to more fully understand associations between psychological stress and health, it is helpful for researchers to identify "psychobiomarkers," or biological measures that are regulated in part by psychological function and that predict longevity. Telomere length appears to be such a measure. Telomeres, the protective caps at the tips of chromosomes, shorten with age, and this shortening predicts disease and longevity. Leukocyte telomere length may be best viewed through a life-span approach, as it reflects in part the cumulative number of cell divisions that have occurred and the long-term biochemical environment. Recently, a critical mass of studies demonstrated that telomeres appear to shorten with chronic stress, although the mechanisms are unknown. This paper reviews what appear to be malleable determinants of rate of telomere attrition, focusing on early life chronic stressors and metabolic adversity (poor nutrition during development, and obesity). The next generation of research will benefit from experimental and longitudinal models integrating genetic variation, social environments, life experience, and health behaviors.     

An Intricate Dance: Life Experience,Multisystem Resiliency,and Rate of Telomere Decline Throughout the Lifespan

Accumulation of life stressors predicts accelerated development and progression of diseases of aging. Telomere length, the DNA‐based biomarker indicating cellular aging, is a mechanism of disease development, and is shortened in a dose response fashion by duration and severity of life stressor exposures. Telomere length captures the interplay between genetics, life experiences and psychosocial and behavioral factors. Over the past several years, psychological stress resilience, healthy lifestyle factors, and social connections have been associated with longer telomere length and it appears that these factors can protect individuals from stress‐induced telomere shortening. In the current review, we highlight these findings, and illustrate that combining these ‘multisystem resiliency’ factors may strengthen our understanding of aging, as these powerful factors are often neglected in studies of aging. In naturalistic studies, the effects of chronic stress exposure on biological pathways are rarely main effects, but rather a complex interplay between adversity and resiliency factors. We suggest that chronic stress effects can be best understood by directly testing if the deleterious effects of stress on biological aging processes, in this case the cell allostasis measure of telomere shortening, are mitigated in individuals with high levels of multisystem resiliency. Without attending to such interactions, stress effects are often masked and missed. Taking account of the cluster of positive buffering factors that operate across the lifespan will take us a step further in understanding healthy aging. While these ideas are applied to the telomere length literature for illustration, the concept of multisystem resiliency might apply to aging broadly, from cellular to systemic health.     

A meta-analysis of the relationship between anxiety and telomere length

Background and objectives: Telomeres are protective caps at the ends of chromosomes, and shorter telomeres are associated with poor physical health. The present study set out to consolidate the varying effect sizes found so far in studies of anxiety and telomere length.

Design and methods: A meta-analytic investigation of the relationship between anxiety and telomere length used information from 17 different samples comprising a total of 19,424 participants.

Results: The results showed a small but significant association, r?=??.06, between higher anxiety and shorter telomeres. Studies comparing individuals diagnosed with an anxiety disorder with other individuals had a significant effect size, and studies that did not use this comparison threshold did not have a significant effect size.

Conclusions: Anxiety is associated with an important biomarker related to health. Future experimental studies that examine the impact of interventions intended to reduce anxiety in conjunction with measurement of telomere length can further clarify the impact of anxiety on telomere length.     

It's more than skin‐deep: The relationship between social victimization and telomere length in adolescence

This study examined the relationship between peer victimization and telomere length (TL), an indicator of biological aging that is associated with stressors (Epel, 2009). It was predicted that social victimization would have a greater impact upon TL, as well as the frequency and severity of health complaints than physical victimization. Adolescents (M_age = 15.91 years, SD_age = 1.65) and their parents completed measures of peer victimization and physical health problems; adolescents also submitted a DNA sample for telomere analysis. Greater instances of being socially, but not physically, victimized were associated with shorter telomeres, as well as more frequent and severe health complaints. TL was also negatively related to both the frequency and severity of health problems, even after controlling for BMI, age, and sex of participant. The relationship between social victimization and health complaints via TL held only at higher levels of social victimization. These findings are the first to find an association between peer victimization and shortened telomeres.

     

Volume contents and author index for Volume 10, 2009

Although there are very few published studies on the issue, there is much anecdotal evidence that, despite all its undisputed benefits, meditation practice can have psychologically deleterious effects. In this paper I will describe a body-based model for understanding trauma, the Trauma Resiliency model, and suggest it might be a helpful tool in anticipating, preventing and/or mitigating these effects. I will argue that Buddhist traditions are replete with frameworks, tools and techniques for addressing some of the psychological pitfalls highlighted. However, some of these methods may have been ‘lost in translation’ as Buddhist meditation training has been adapted for a Western audience. I will make the case that, somewhat ironically, in operational terms some of the secular modalities for teaching mindfulness (such as MBSR) may be psychologically ‘safer’ than those offered in a (Western) Buddhist context. I will call for further inquiry about how to mitigate and protect against psychological harms in Buddhist meditation training.     

正念冥想对情绪的调节作用:理论与神经机制

正念冥想可调节个体的负性情绪、促进个体正性情绪,对于心身疾病具有显著的干预效用.正念冥想的再感知模型、正念应对模型、推动性上升螺旋模型以及正念情绪调节模型都强调了正念冥想对情绪的调节作用.认知神经科学的研究发现,正念冥想可促进左侧前额叶脑区激活增强,涉及的脑区主要包括背外侧前额叶皮层(DLPFC)和背内侧前额叶皮层(DMPFC).研究者进一步发现,正念特质是通过改善前额叶对边缘系统反应的调节来实现对情绪的调节作用.而且,这种调节作用还有可能体现为通过冥想训练分离联结在一起的两种自我参照神经机制,从而加强体验性神经机制.另外,研究者还发现,正念冥想训练还可以改变与情绪加工相关的大脑结构.进一步澄清冥想训练与大脑偏侧化的关系和不同类型被试之间的比较研究将成为该领域日后研究的重点.     

The Chemical and Biological Warfare Environment: Psychological Responses and Social Supports in a High-Stress Environment

In order to better understand psychological responses to high-stress environments and the contributions of social supports to mediating the effects of this stress, we conducted a preliminary investigation of a health care delivery team in a simulated chemical and biological warfare (CBW) environment. Our data suggest that state anxiety prior to the exercise, perceived social support from family and friends, and active training stand out as predictors of psychological outcome, even after trait and pre-exercise psychological variables are considered. Interventions directed at state anxiety and active training may offer mechanisms to decrease the psychological distress of the high-stress environment. Future research should examine variables which are amenable to intervention to determine if they are causally related to health outcome in high-stress environments.     

The relationship between positive psychological characteristics and longer telomeres

Objective: Longer telomeres are associated with better health and longevity. This research investigated the relationship between positive psychological dispositional traits and telomere length. Positive traits examined were typical high positive affect, typical low negative affect, life satisfaction, trait mindfulness, trait emotional intelligence, general self-efficacy and optimism.

Design and Measures: One hundred and twenty women and men, with a mean age of 40.92, completed measures of positive characteristics and provided samples for telomere length analysis.

Results: Together the positive dispositional characteristics explained significant variance in telomere length, R = .40. Among the individual characteristics, greater optimism and higher emotional intelligence were associated with longer telomeres after adjustment for age and gender and the association between optimism and telomere length remained significant after adjusting for age and gender as well as the other positive characteristics, with a partial correlation r of .30.

Conclusion: These results in conjunction with previous research findings provide a platform for further exploration of biological pathways connecting positive characteristics such as optimism to telomere length and investigation of the impact of increasing a characteristic such as optimism on telomere functioning.     

The protective effects of brief mindfulness meditation training

Mindfulness meditation has gained a great deal of attention in recent years due to the variety of physical and psychological benefits, including improved working memory, decreased mind wandering and reduced impact of stress on working memory. The current study examined a 1-week at home mindfulness meditation intervention compared to an active control intervention. Results suggest that mindfulness meditation does not increase working memory or decrease mind wandering but does prevent stress related working memory impairments. Mindfulness meditation appears to alter the factors that impair working memory such that the negative impact of mind wandering on working memory was only evident at higher levels of negative affect. The use of cognitive mechanism words in narratives of stressful events did not differ by condition but predicted poorer working memory in the control condition. The results support the use of an at home mindfulness meditation intervention for reducing stress-related impairments.     

Mindfulness and self-compassion as predictors of psychological wellbeing in long-term meditators and matched nonmeditators

Mindfulness training has well-documented effects on psychological health. Recent findings suggest that increases in both mindfulness and self-compassion may mediate these outcomes; however, their separate and combined effects are rarely examined in the same participants. This study investigated cross-sectional relationships between self-reported mindfulness, self-compassion, meditation experience, and psychological wellbeing in 77 experienced meditators and 75 demographically matched nonmeditators. Most mindfulness and self-compassion scores were significantly correlated with meditation experience and psychological wellbeing. Mindfulness and self-compassion accounted for significant independent variance in wellbeing. A significant relationship between meditation experience and wellbeing was completely accounted for by a combination of mindfulness and self-compassion scores. Findings suggest that both mindfulness and self-compassion skills may play important roles in the improved wellbeing associated with mindfulness training; however, longitudinal studies are needed to confirm these findings.