情景记忆成功年老化的神经机制

随着年龄的增长, 大部分老年人的情景记忆会出现衰退, 但也会有一部分老年人的情景记忆表现出成功的年老化, 即记忆成绩较好或随增龄的衰退程度较小。脑保持理论、神经去分化理论、认知储备理论以及神经补偿理论分别从不同角度解释了情景记忆成功年老化的神经机制。基于选择性优化与补偿模型对现有理论进行整合, 发现情景记忆成功年老化可能与个体的认知储备水平直接相关：高认知储备的老年人能够对情景记忆相关的脑区和脑网络进行优化且具备更强的神经补偿能力, 因而其脑功能(比如, 神经表征和神经加工通路的特异性)可能会保持地更好。未来研究需要更多地采用纵向设计来考察各理论之间的关系及其影响因素, 从而更好地解释记忆成功年老化的神经机制并为提升老年人的脑与认知健康提供支持。     

Alcoholism,Aging, and Cognition: A Review of Evidence for Shared or Independent Impairments

Little is known about the combined effects of aging and alcoholism on cognitive function, in spite of the potential importance of this knowledge. Studies reported to date have focused on whether aging and alcoholism have shared mechanisms (i.e., the premature aging hypothesis) or independent mechanisms. Most have concluded that the effects of aging and alcoholism on cognition operate through independent mechanisms. However, there are reasons to doubt this conclusion. Many of the studies were not optimally designed to discover shared mechanisms because they used a limited range of ages, included several different groups in their analyses, or had low statistical power. Furthermore, interpretation of the patterns of main effects and interactions between aging and alcoholism is not straightforward. Assumptions must be made about the nature of the impairments in order to interpret the data. This review uses several theories of cognitive aging as an organizing heuristic for interpreting the extant data on aging, cognition, and alcoholism. Some potential shared mechanisms for cognitive deficits in aging and alcoholism are identified, such as information processing speed and proactive interference in working memory. In contrast, some potential independent mechanisms are also identified, such as decay from working and long-term memory. These mechanisms should be used as a base to guide necessary further research.     

Face memory and hemispheric preference: Emotionality and extraversion

Subjects made arousing or nonarousing judgments about photographs of strangers, then had an unannounced recognition test over the photographs. Emotional orienting tasks led to better retention than nonemotional tasks. Assuming emotionality is predominantly a right-hemisphere activity, then this result is consistent with other research showing a right-hemisphere advantage in processing faces. This difference was most clear for subjects with a right-hemisphere cognitive style. Extraversion had no effect on face recognition, nor did a subject's cognitive style seem to be associated with extraversion or neuroticism scores.     

Are variations among right-handed individuals in perceptual asymmetries caused by characteristic arousal differences between hemispheres?

We propose that much of the variance among right-handed subjects in perceptual asymmetries on standard behavioral measures of laterality arises from individual differences in characteristic patterns of asymmetric hemispheric arousal. Dextrals with large right-visual-field (RVF) advantages on a tachistoscopic syllable-identification task (assumed to reflect characteristically higher left-hemisphere than right-hemisphere arousal) outperformed those having weak or no visual-field asymmetries (assumed to reflect characteristically higher right-hemisphere than left-hemisphere arousal). The two groups were equal, however, in asymmetries of error patterns that are thought to indicate linguistic or nonlinguistic encoding strategies. For both groups, relations between visual fields in the ability to discriminate the accuracy of performance followed the pattern of syllable identification itself, suggesting that linguistic and metalinguistic processes are based on the same laterally specialized functions. Subjects with strong RVF advantages had a pessimistic bias for rating performance, and those with weak or no asymmetries had an optimistic bias, particularly for the left visual field (LVF). This is concordant with evidence that the arousal level of the right hemisphere is closely related to affective mood. Finally, consistent with the arousal model, leftward asymmetries on a free-vision face-processing task became larger as RVF advantages on the syllable task diminished and as optimistic biases for the LVF, relative to the RVF, increased.     

Information processing,neuropsychological function,and the inherited predisposition to alcoholism

Sons of male alcoholics are at particularly heightened risk for the development of alcoholism. This heightened risk frequently appears in association with increased incidence of conduct disorder or hyperactivity, with deficits in abstract thinking and poor school performance, with abnormalities in cued psychophysiological response, and with increased sensitivity to the putatively stress-response-dampening effects of alcohol intoxication. This risk and its associated features are discussed within the context of a neuropsychological theory, predicated on the notions (1) that deficits in cognitive functions theoretically dependent upon the intact functioning of the prefrontal cortex could underlie manifestation of the idiosyncracies commonly attributed to sons of male alcoholics, and (2) that acute alcohol intoxication could relieve the subjective discomfort associated with the consequences of such deficits.     

No protective effects of education during normal cognitive aging: results from the 6-year follow-up of the Maastricht Aging Study

Recent large-scale longitudinal aging studies question earlier claims that higher education protects against cognitive decline in older age. In the present study, the authors addressed this issue by determining whether educational level had an attenuating effect on the rate of cognitive change assessed with a broad range of neuropsychological tests in a community sample of 872 healthy individuals aged 49 to 81 years at baseline. The participants were followed for 6 years and were tested 3 times (at baseline and at 3 and 6 years after baseline). Results of linear mixed-model analyses showed that education had no significant effect on cognitive change over time. These results are discussed in terms of the age range of the sample, definition and range of education, cognitive measures used, length of the study and number of consecutive assessments, and confounding effect of health. The findings question the extent of the presumed protective effects of higher education on cognitive decline during normal aging.     

Neuropsychological Contributions to the Early Identification of Alzheimer’s Disease

A wealth of evidence demonstrates that a prodromal period of Alzheimer’s disease (AD) exists for some years prior to the appearance of significant cognitive and functional declines required for the clinical diagnosis. This prodromal period of decline is characterized by a number of different neuropsychological and brain changes, and reliable identification of individuals prior to the development of significant clinical symptoms remains a top priority of research. In this review we provide an overview of those neuropsychological changes. In particular, we examine specific domains of cognition that appear to be negatively affected during the prodromal period of AD, and we review newer analytic strategies designed to examine cognitive asymmetries or discrepancies between higher-order cognitive functions versus fundamental skills. Finally, we provide a critical examination of the clinical concept of Mild Cognitive Impairment and offer suggestions for an increased focus on the impact of cerebrovascular disease (CVD) and CVD risk during the prodromal period of AD.     

Cognitive function, physical activity, and aging: possible biological links and implications for multimodal interventions

Increasing evidence shows the positive effect of physical activity (PA) on maintaining cognitive function. Both processes seem intrinsically linked to each other. The most likely mechanism is a reciprocal stimulation of neuroplasticity. Based on extensive experimental work on animals and humans, the concept of an enriched environment, including PA and challenging cognitive tasks, has provided the basis to systematically assess possible interventions for successful aging. I will use recent findings on brain mechanisms associated with PA and its effects on higher cognitive function at a systems and molecular level to demonstrate the need to design effective interventions. Such interventions should be designed to take advantage of the presumed compensatory mechanisms of elderly individuals, thereby limiting functional decline in higher cognitive performance in aging people. My review of the most recent relevant publications concerning this topic supports the notion that it is a promising approach to provide cognitive training and PA in conjunction, since the combination may generate synergistic beneficial changes than either one individually. Multimodal training programs should therefore be tested. However, at present there is insufficient evidence to conclude that multimodal interventions are superior to isolated cognitive or physical exercise interventions, since major studies addressing this topic are lacking. These studies are needed to conclusively prove that both strategies will positively interact when used in combined interventions. Finally the use of modern technology for these interventions will be discussed.     

Family Process as a Mediator of the Negative Effects of Parental Alcoholism on Young Adult Dating Relationships

The effects of parental alcoholism on young adult dating relationship quality (trust, intimacy, commitment, and satisfaction) were considered in the context of the mediating variable of family process (cohesion, conflict resolution, and family competence). A model was tested with a sample of 287 young adults (95 were adult children of alcoholics) that suggested that healthier family process mediates the negative effects of having an alcoholic parent on dating relationship quality. Structural equation modeling results showed that the model fit the data. Young adults from alcoholic families in which family process was less negatively affected by parental alcoholism were less likely to report lower dating relationship quality than those from families in which family process was more negatively affected by parental alcoholism. Parental divorce was directly related to lower relationship quality. Clinical implications for working with young adult children of alcoholics are discussed.     

Executive function, intellectual decline and daily living skills

Understanding the cognitive changes associated with compromised daily living skills in elderly individuals is important for making appropriate recommendations about the capacity for independent functioning. To this end, we retrospectively examined data from 92 elderly individuals presenting with cognitive decline who were administered measures of executive functioning, general intelligence, and daily living skills. Multiple regression analyses were used to examine the relationship between executive functioning and daily living skills, while controlling for age, depression, and either IQ decline or current IQ. Executive functioning accounted for additional variance in a broad range of daily living skills after controlling for IQ decline. When FSIQ was used in the regression model rather than IQ decline, executive functioning was no longer uniquely associated with daily living skills. Executive functions appear to be important for daily living skills until a critical threshold of low intellectual functioning is reached, reflecting the combined influence of premorbid ability and the extent of intellectual decline. Our results suggest that understanding the relative contribution of different cognitive domains to functional decline in elderly individuals should take into account general intellectual functioning and estimated decline, and that the initiation and/or persistence of self-directed cognitive processes may be important for adaptive daily functioning. These findings have implications for making more evidence-based recommendations about the capacity for independent living.     

Alcohol challenge with sons of alcoholics: a critical review and analysis

Studies are reviewed in which response to acute administration of alcohol was compared between individuals with and without family histories of alcoholism (FH+, FH-). This research represents a search for a psychobiological marker for alcoholism. A methodological critique of the procedures reported in this literature is then presented. Finally, a conceptual model is suggested in which differences in the response to alcohol between FH+ individuals and FH- individuals must be understood in relation to time after drinking alcohol. This Newtonian differentiator model proposes that sons of alcoholics exhibit acute sensitization as blood alcohol level rises and acute tolerance as blood alcohol level falls, compared with sons of nonalcoholics. Therefore, FH+ subjects find alcohol more rewarding because they accentuate the pleasurable, excitatory aspects of initial intoxication and attenuate the feelings of anxiety and depression that predominate as blood alcohol levels drop.     

Executive Function,Intellectual Decline and Daily Living Skills

ABSTRACT

Understanding the cognitive changes associated with compromised daily living skills in elderly individuals is important for making appropriate recommendations about the capacity for independent functioning. To this end, we retrospectively examined data from 92 elderly individuals presenting with cognitive decline who were administered measures of executive functioning, general intelligence, and daily living skills. Multiple regression analyses were used to examine the relationship between executive functioning and daily living skills, while controlling for age, depression, and either IQ decline or current IQ. Executive functioning accounted for additional variance in a broad range of daily living skills after controlling for IQ decline. When FSIQ was used in the regression model rather than IQ decline, executive functioning was no longer uniquely associated with daily living skills. Executive functions appear to be important for daily living skills until a critical threshold of low intellectual functioning is reached, reflecting the combined influence of premorbid ability and the extent of intellectual decline. Our results suggest that understanding the relative contribution of different cognitive domains to functional decline in elderly individuals should take into account general intellectual functioning and estimated decline, and that the initiation and/or persistence of self-directed cognitive processes may be important for adaptive daily functioning. These findings have implications for making more evidence-based recommendations about the capacity for independent living.     

Inherited predisposition to alcoholism: characteristics of sons of male alcoholics

Sons of male alcoholics (SOMAs) are at markedly heightened genetic risk for the development of alcohol abuse. Study of SOMAs could therefore conceivably increase the efficiency of research aimed at uncovering those heritable factors that predispose to alcoholism. SOMAs manifest observable behavioral, cognitive, and psychophysiological abnormalities while sober and react idiosyncratically to alcohol intoxication. They are most commonly described as conduct disordered and hyperactive, appear heir to a variety of deficits in verbal and abstract cognition, and perform more poorly in the academic environment. SOMAs are characterized by abnormal patterns of cued psychophysiological response, and appear more sensitive to the putatively reinforcing aspects of alcohol intoxication. Various methodological weaknesses permeate the relevant literature. Some straightforward improvements are suggested.     

Functional Disability in Mild Cognitive Impairment: A Systematic Review and Meta-Analysis

Accumulating evidence suggests that the pre-dementia syndrome mild cognitive impairment (MCI) is characterized by decrements in instrumental activities of daily living (IADL). The current review was a quantitative synthesis of the available literature to objectively characterize IADL disability in MCI while clarifying inconsistencies in findings across studies. It was hypothesized that individuals with MCI would display significantly greater functional impairment relative to cognitively intact controls. Candidate moderators specified a priori included functional assessment approach, MCI subtype, depressive symptoms, and language conducted. Online databases (PubMed/MEDLINE and PsycINFO) and reference lists were searched to identify peer-reviewed publications assessing IADL in MCI compared to normal aging. A total of 151 effect sizes derived from 106 studies met inclusionary criteria (N?=?62,260). Random effects models yielded a large overall summary effect size (Hedges’ g?=?0.76, 95 % confidence interval: 0.68???0.83, p?<?.001) confirmed in multi-level analyses adjusted for nesting of effect sizes within studies (g?=?0.78, 95 % confidence interval: 0.69???0.87). Functional assessment strategy and MCI subtype were significant moderators of effect size, whereas depressive symptoms and language were not. Results convincingly demonstrate that MCI is associated with significant difficulties in the performance of complex everyday tasks. It appears that functional decline, like cognitive decline, exists on a continuum from healthy aging to dementia onset. Implications for clinical practice and research priorities are discussed.     

基因-大脑-行为框架下的抑制控制与老化

抑制控制能力是认知功能的重要成分。神经影像研究表明, 老年人抑制控制能力改变与前额叶皮层萎缩、神经元丧失有着密切关系, 抑制过程中前额叶需要以更高水平的激活达到代偿目的。遗传学研究表明, 抑制控制相关认知老化具有个体差异性, 大脑结构功能对个体差异的作用会出现衰退, 而遗传变异作用逐渐增加, 并使之成为认知老化个体差异性的主要原因之一。未来研究应利用遗传影像学, 结合影像学和遗传学优势, 在基因、大脑和行为框架下探索抑制控制与老化。     

Studying individual aging in an interindividual context: typical paths of age-related, dementia-related, and mortality-related cognitive development in old age

This study has 2 objectives: (a) to explore typical paths of cognitive development associated with aging, terminal decline, and dementia and (b) to promote and illustrate an individual-oriented approach to the study of cognitive aging based on longitudinal panel data from a population-based sample (N = 500; age range-sub(T1)= 60-80, where T refers to time) tested at 3 occasions 5 years apart. Results document interindividual differences in multivariate patterns of change. Although cognitive changes generally covary, the present study indicates that subgroups of individuals develop along different paths characterized by selective changes in subsets of cognitive functions. Typical progression of dementia followed a developmental cascade from low declarative memory, via low functioning across all observed cognitive measures, to dementia diagnosis, and finally, death.     

Enhancing the Cognitive Vitality of Older Adults

Aging is associated with decline in a multitude of cognitive processes and brain functions. However, a growing body of literature suggests that age-related decline in cognition can sometimes be reduced through experience, cognitive training, and other interventions such as fitness training. Research on cognitive training and expertise has suggested that age-related cognitive sparing is often quite narrow, being observed only on tasks and skills similar to those on which individuals have been trained. Furthermore, training and expertise benefits are often realized only after extensive practice with specific training strategies. Like cognitive training, fitness training has narrow effects on cognitive processes, but in the case of fitness training, the most substantial effects are observed for executive-control processes.     

Tobacco use, alcohol dependence, and cognitive performance

Chronic alcohol abuse has long been associated with a mild, generalized pattern of cognitive decrements. However, it is important to note that problem drinking rarely occurs in isolation from abuse of other drugs. For people dependent upon alcohol, tobacco is one of the mostly commonly coabused substances. Recent research suggests that individuals with alcohol dependency may gravitate toward tobacco use, in part, because of the positive effects of nicotine on aspects of cognitive performance that may be compromised as a consequence of chronic alcohol misuse. In this article, the author focuses on the effects of nicotine on behavioral and electrophysiological indexes of cognitive performance, and the impact of these effects on alcohol-related cognitive decrements. The author discusses implications of these findings in the context of treatment and recovery of people with alcoholism.     

Women and Alcoholism: A Biopsychosocial Perspective and Treatment Approaches

Viewing alcoholism in women from a biopsychosocial perspective reveals a unique set of circumstances and challenges that women alcoholics face when compared with men. Biologically, women react differently to alcohol ingestion than do men. Women reach higher blood alcohol levels and sustain more somatic and cognitive damage than men when consuming equivalent amounts of alcohol. Psychosocially, women alcoholics face societal rebuke and chastisement of a greater magnitude than do men. Finally, barriers to treatment faced by women, such as the need for child care, cost of treatment, familial opposition, denial of alcoholism, and inadequate diagnostic training of physicians, must be overcome to create successful treatment approaches for the female alcoholic. Obstacles to and implications for treatment are also discussed.