发展性阅读障碍的生理基础

发展性阅读障碍是关系人类健康和发展的重要课题,对其产生机制的探讨有利于寻找适当的治疗方法.文章在简要回顾阅读障碍的界定、研究内容和有关理论争论基础上,重点介绍了阅读障碍的神经基础和遗传机制.文章从大脑结构和功能单侧化、完成认知任务时大脑的激活模式、激活时间进程以及视觉巨细胞等方面介绍了发展性阅读障碍者与正常读者之间存在的差异.文章还指出许多双生子研究都发现同孪双生子的阅读障碍同现率高于异孪双生子,尤其是近期的遗传学研究鉴定出几个与阅读障碍有关的染色体,如6号和15号染色体与语音障碍和拼写障碍有关.这些研究结果说明发展性阅读障碍有一定的脑神经基础和遗传基础.     

Parent-reported executive functioning in young children treated for cancer

It is well known that children treated for cancer are at risk for cognitive and functional impairments. Such research is largely based on studies of late effects in school-aged or older children. However, far less is known about executive function weaknesses in preschool-aged children treated for cancer. Thus, the aim of this study was to examine executive functioning in a clinically referred sample of young oncology patients, and its association with broader domains of functioning. Data from 61 young children with cancer, who were referred for clinical cognitive evaluations, were abstracted and included in this study. Patients were 5.00 years of age (SD = 0.72) at assessment, 54.1% male, and two-thirds (63.9%) had been treated for brain tumors. Most executive functions were significantly discrepant from the mean, with 47.5% of preschoolers having parent-reported working memory concerns within the clinically significant range. There were no differences in executive functioning based on diagnosis or treatment status. Parent-reported executive functioning was strongly correlated with global intelligence and adaptive functioning, with some indices also associated with nonverbal problem solving and pre-academic skills. Ultimately, results indicate the presence of emerging weaknesses in executive functioning in young children with cancer, and add to a growing body of literature highlighting the potential cognitive and behavioral risks associated with a cancer diagnosis in early childhood.     

Parent Report of Attention Problems Predicts Later Adaptive Functioning in Children with Brain Tumors

Children with brain tumors are at risk for psychological and behavioral difficulties. This study examined the ability of parent report of attention problems, withdrawal, anxiety, and depression, as well as IQ, to predict later adaptive functioning in 42 children treated for brain tumors. Age at diagnosis, SES, gender, and scores on the Neurological Predictor Scale (NPS) also were examined as predictors. Parent report of attention problems, SES, and NPS were significant predictors of later adaptive functioning across domains. This finding highlights the ability of parent report of attention problems to predict later adaptive functioning in children treated for brain tumors.     

执行功能与攻击行为关系的研究

攻击行为产生的原因十分复杂,受当今认知神经科学的影响,心理学研究人员从执行功能的角度来探讨攻击行为。现有的研究主要从心理学、流行病学、行为神经学、神经心理学和神经成像角度,考察和分析二者内在的关联,结果表明在暴力犯罪、反社会人格、杀人犯、精神病患者、少年犯、注意缺陷-多动障碍等群体,执行功能与攻击行为间存在很强的负向关联。将来的研究需要拓宽研究被试群体,深入考察内在的脑机制,制定恰当的攻击行为干预方法。     

Childhood socioeconomic status and the pace of structural neurodevelopment: accelerated,delayed, or simply different?

Socioeconomic status (SES) is associated with children’s brain and behavioral development. Several theories propose that early experiences of adversity or low SES can alter the pace of neurodevelopment during childhood and adolescence. These theories make contrasting predictions about whether adverse experiences and low SES are associated with accelerated or delayed neurodevelopment. We contextualize these predictions within the context of normative development of cortical and subcortical structure and review existing evidence on SES and structural brain development to adjudicate between competing hypotheses. Although none of these theories are fully consistent with observed SES-related differences in brain development, existing evidence suggests that low SES is associated with brain structure trajectories more consistent with a delayed or simply different developmental pattern than an acceleration in neurodevelopment.     

Neurocognitive correlates of socioeconomic status in kindergarten children

Socioeconomic status (SES) is strongly associated with cognitive ability and achievement during childhood and beyond. Little is known about the developmental relationships between SES and specific brain systems or their associated cognitive functions. In this study we assessed neurocognitive functioning of kindergarteners from different socioeconomic backgrounds, using tasks drawn from the cognitive neuroscience literature in order to determine how childhood SES predicts the normal variance in performance across different neurocognitive systems. Five neurocognitive systems were examined: the occipitotemporal/visual cognition system, the parietal/spatial cognition system, the medial temporal/memory system, the left perisylvian/language system, and the prefrontal/executive system. SES was disproportionately associated with the last two, with low SES children performing worse than middle SES children on most measures of these systems. Relations among language, executive function, SES and specific aspects of early childhood experience were explored, revealing intercorrelations and a seemingly predominant role of individual differences in language ability involved in SES associations with executive function.     

Executive functioning and health-related quality of life in pediatric sickle cell disease

Research consistently indicates that children with sickle cell disease (SCD) face multiple risk factors for neurocognitive impairment. Despite this, no empirical research to date has examined the impact of neurocognitive functioning on quality of life for this pediatric group. Thus, the current study aims to examine the relationship between executive functioning and quality of life in a sample of children with SCD and further explore psychosocial and family/caregiver resources as moderators of this relationship. A total of 45 children with SCD aged 8 to 16 years and their caregivers completed measures of quality of life, behavioral ratings of executive functioning, and psychosocial functioning. Hierarchical linear regression models were utilized to determine the impact of executive functioning on quality of life and further test the interaction effects of proposed moderating variables. Controlling for age, pain, and socioeconomic status (SES), executive functioning was found to significantly predict child- and parent-reported quality of life among youth with SCD. Psychosocial resources of the primary caregiver or family was not found to moderate the relationship between executive functioning and quality of life. These results provide the first empirical evidence that lower executive skills negatively predict quality of life for children with SCD, supporting clinical and research efforts which aim to establish efficacious interventions that target cognitive decrements within this pediatric population.     

Does impaired socioemotional functioning account for behavioral dysexecutive disorders? Evidence from a transnosological study

Behavioral dysexecutive disorders are highly prevalent in patients with neurological diseases but cannot be explained by cognitive dysexecutive impairments. In fact, the underlying mechanisms are poorly understood. Given that socioemotional functioning underlies appropriate behavior, socioemotional impairments may contribute to the appearance of behavioral disorders. To investigate this issue, we performed a transnosological study.

Seventy-five patients suffering from various neurological diseases (Alzheimer’s disease (AD), Parkinson’s disease (PD), frontotemporal lobar degeneration, and stroke) were included in the study. The patients were comprehensively assessed in terms of cognitive and behavioral dysexecutive disorders and socioemotional processes (facial emotion recognition and theory of mind). As was seen for cognitive and behavioral dysexecutive impairments, the prevalence of socioemotional impairments varied according to the diagnosis. Stepwise logistic regressions showed that (i) only cognitive executive indices predicted hypoactivity with apathy/abulia, (ii) theory of mind impairments predicted hyperactivity–distractibility–impulsivity and stereotyped/perseverative behaviors, and (iii) impaired facial emotion recognition predicted social behavior disorders. Several dysexecutive behavioral disorders are associated with an underlying impairment in socioemotional processes but not with cognitive indices of executive functioning (except for apathy). These results strongly suggest that some dysexecutive behavioral disorders are the outward signs of an underlying impairment in socioemotional processes.     

The neuroanatomy and neuroendocrinology of fragile X syndrome

Fragile X syndrome (FXS), caused by a single gene mutation on the X chromosome, offers a unique opportunity for investigation of gene-brain-behavior relationships. Recent advances in molecular genetics, human brain imaging, and behavioral studies have started to unravel the complex pathways leading to the cognitive, psychiatric, and physical features that are unique to this syndrome. In this article, we summarize studies focused on the neuroanatomy and neuroendocrinology of FXS. A review of structural imaging studies of individuals with the full mutation shows that several brain regions are enlarged, including the hippocampus, amygdala, caudate nucleus, and thalamus, even after controlling for overall brain volume. These regions mediate several cognitive and behavioral functions known to be aberrant in FXS such as memory and learning, information and sensory processing, and social and emotional behavior. Two regions, the cerebellar vermis, important for a variety of cognitive tasks and regulation of motor behavior, and the superior temporal gyrus, involved in processing complex auditory stimuli, are reported to be reduced in size relative to controls. Functional imaging, typically limited to females, has emphasized that individuals with FXS do not adequately recruit brain regions that are normally utilized by unaffected individuals to carry out various cognitive tasks, such as arithmetic processing or visual memory tasks. Finally, we review a number of neuroendocrine studies implicating hypothalamic dysfunction in FXS, including abnormal activation of the hypothalamic-pituitary-adrenal (HPA) axis. These studies may help to explain the abnormal stress responses, sleep abnormalities, and physical growth patterns commonly seen in affected individuals. In the future, innovative longitudinal studies to investigate development of neurobiologic and behavioral features over time, and ultimately empirical testing of pharmacological, behavioral, and even molecular genetic interventions using MRI are likely to yield significant positive changes in the lives of persons with FXS, as well as increase our understanding of the development of psychiatric and learning problems in the general population.     

Oscillatory gamma activity mediates the pathway from socioeconomic status to language acquisition in infancy

BackgroundThe predictable path to child language acquisition is largely constrained by both brain maturation and environmental experience. The synchronized activity of large numbers of neurons gives rise to macroscopic brain oscillations on an electroencephalogram (EEG). It has been found that neural oscillations at rest in the gamma frequency band (25–45 Hz) are associated with development of different cognitive systems, including language. Although the etiology of language is explained by genetically driven brain maturation factors, environment plays a significant role. Specifically, candidate pathways from environment to language development include sociodemographic factors, primarily socioeconomic status (SES) which is likely to exert its effects on language development through other factors, such as parenting style.Despite these assumptions, no studies have so far examined the interrelation between brain maturation factors such as gamma frequency oscillatory activity, environmental factors such as SES, and language acquisition.Aim and methodIn a longitudinal study of 84 Italian typically developing infants, we measured the power of oscillatory gamma activity as mediator between SES and language acquisition. Baseline EEG and information about SES were collected when infants were aged 6 months. Children were followed-up longitudinally to measure expressive vocabulary and Mean Length of Utterance (MLU) at 24 months.ResultsThe mediation model showed that SES is associated with gamma power which, in turn, is associated with expressive language at age 24 months. A higher SES predicted an increase in left central gamma power which, in turn, predicted better language scores.ConclusionsThese results confirm the predictive role of gamma activity oscillatory activity on later language acquisition, suggesting a specific role for these oscillatory mechanisms in language development milestones such as vocabulary development and early word combination. Furthermore, they suggest that SES differences in brain activity may be apparent at early stages of life and affect later language skills. If replicated, our findings could contribute to identifying highest-risk children and may prompt cost-effective preventive/treatment strategies.     

宽恕心理的行为测量及认知神经机制

宽恕是一个复杂的心理过程,被认为是对冒犯者的亲社会化转变的过程,包括认知、情绪、动机和行为上的改变。本文回顾了国内外宽恕心理的行为测量范式和认知神经机制研究相关的成果,发现宽恕心理的行为测量范式能够揭示宽恕相关的心理过程;认知神经机制的研究发现宽恕心理过程主要涉及负责社会认知、共情和认知控制等功能的脑区。未来的研究应关注宽恕心理行为测量范式的有效性和揭示内容的一致性、宽恕心理的认知和脑神经基础。     

Alcohol-related amnesia and dementia: animal models have revealed the contributions of different etiological factors on neuropathology, neurochemical dysfunction and cognitive impairment

Chronic alcoholism is associated with impaired cognitive functioning. Over 75% of autopsied chronic alcoholics have significant brain damage and over 50% of detoxified alcoholics display some degree of learning and memory impairment. However, the relative contributions of different etiological factors to the development of alcohol-related neuropathology and cognitive impairment are questioned. One reason for this quandary is that both alcohol toxicity and thiamine deficiency result in brain damage and cognitive problems. Two alcohol-related neurological disorders, alcohol-associated dementia and Wernicke-Korsakoff syndrome have been modeled in rodents. These pre-clinical models have elucidated the relative contributions of ethanol toxicity and thiamine deficiency to the development of dementia and amnesia. What is observed in these models--from repeated and chronic ethanol exposure to thiamine deficiency--is a progression of both neural and cognitive dysregulation. Repeated binge exposure to ethanol leads to changes in neural plasticity by reducing GABAergic inhibition and facilitating glutamatergic excitation, long-term chronic ethanol exposure results in hippocampal and cortical cell loss as well as reduced hippocampal neurotrophin protein content critical for neural survival, and thiamine deficiency results in gross pathological lesions in the diencephalon, reduced neurotrophic protein levels, and neurotransmitters levels in the hippocampus and cortex. Behaviorally, after recovery from repeated or chronic ethanol exposure there is impairment in working or episodic memory that can recover with prolonged abstinence. In contrast, after thiamine deficiency there is severe and persistent spatial memory impairments and increased perseverative behavior. The interaction between ethanol and thiamine deficiency does not produce more behavioral or neural pathology, with the exception of reduction of white matter, than long-term thiamine deficiency alone.     

Chronic Pain and Neuropsychological Functioning

This review article examines the effect of chronic pain on neuropsychological functioning. Primary attention is given to studies that include patient groups without a history of traumatic brain injury (TBI) or neurologic disorders. Numerous studies were identified that demonstrate neuropsychological impairment in patients with chronic pain, particularly on measures assessing attentional capacity, processing speed, and psychomotor speed. Despite suggestive findings, further studies are needed to clarify the variables that mediate the impact of pain on neuropsychological functioning and the unique role of various symptoms often associated with chronic pain.     

The relationship of young adolescent Children's Depression Inventory (CDI) scores to their social and cognitive functioning

The relationship of young adolescents' scores on the Children's Depression Inventory (CDI) to subjective and objective indices of their social and cognitive functioning was examined. Subjects were 89 young adolescents (11–15 years old), their parents, and their social studies teachers. The correlations of adolescents' CDI scores with recent school grades, objective ratings of overt social behavior, and measures of adolescent social and cognitive competence as perceived by the adolescent, both parents, and the teacher were examined. CDI scores were significantly and negatively correlated with school grades, behavioral ratings of positive social communication, and adolescent, mother, father, and teacher perceptions of the adolescents' social and cognitive competence. The relationship of these findings to those of other CDI validity studies is discussed.This research was supported, in part, by the William T. Grant Foundation and the University of Georgia's Institute for Behavioral Research.     

Brain activation and the phonological loop: the impact of rehearsal

Brain activation studies offer valuable techniques for exploring human cognition to complement behavioral measures and several studies report a wide range of neuroanatomical networks activated during verbal immediate memory. Behavioral investigations have shown use of multiple cognitive strategies across and within individuals, although aggregate data appear to reflect a common cognitive function. Variation in cognitive strategies could result in aggregate activation patterns that are relatively widespread and difficult to interpret. Imaging data (fMRI) from six participants instructed to use subvocal rehearsal showed significant left hemisphere activation in the inferior parietal gyrus and inferior and middle frontal gyri, a pattern of activation more clearly focused than in previous brain activation studies of immediate verbal serial ordered recall. Our results should be relatively free of the influence of other mental operations, and emphasise the importance of considering which cognitive strategies might give rise to focused or to diverse patterns of brain activation.     

Intelligence and neural efficiency: Measures of brain activation versus measures of functional connectivity in the brain

The neural efficiency hypothesis of intelligence suggests a more efficient use of the cortex (or even the brain) in brighter as compared to less intelligent individuals. This has been shown in a series of studies employing different neurophysiological measurement methods and a broad range of different cognitive task demands. However, most of the studies dealing with the brain–IQ relationship used parameters of absolute or relative brain activation such as the event-related (de-)synchronization of EEG alpha activity, allowing for interpretations in terms of more or less brain activation when individuals are confronted with cognitively demanding tasks. In order to investigate the neural efficiency hypothesis more thoroughly, we also used measures that inform us about functional connectivity between different brain areas (or functional coupling, respectively) when engaged in cognitive task performance. Analyses reveal evidence that higher intelligence is associated with a lower brain activation (or a lower ERD, respectively) and a stronger phase locking between short-distant regions of the frontal cortex.     

Functional neuroimaging of working memory in survivors of childhood brain tumors and healthy children: Associations with coping and psychosocial outcomes

Purpose: Pediatric brain tumors are the second most common cancer diagnosis in individuals under age 20 and research has documented significant neurocognitive, psychosocial, and emotional late effects. Associations among these deficits have not been adequately considered and the role of survivors’ coping with stress in relation to deficits is unknown. Further, research has yet to examine neurobiological processes related to neurocognitive, psychosocial, and emotional difficulties in survivors through the use of functional neuroimaging. Method: Questionnaire measures and functional neuroimaging were used to examine the neurocognitive, psychosocial, and emotional functioning and coping responses of survivors of pediatric brain tumors (N = 17; age 8–16) and healthy children (N = 15). Results: Survivors experienced elevated levels of psychosocial and behavioral/emotional difficulties relative to healthy controls and normative data. Increases in brain activation in prefrontal and other anterior regions in response to a working memory task were associated with better psychosocial functioning, use of engagement coping strategies, and less use of disengagement coping strategies. Regression analyses suggest coping accounts for a significant portion of the association between brain activation and behavioral/emotional functioning. Conclusions: This study extends late-effects research by examining neurobiological processes associated with psychosocial and emotional difficulties. These findings contribute to our understanding of difficulties in survivors and provide a foundation for research exploring these associations and mediators of deficits in future longitudinal studies.     

The effects of socioeconomic status on working memory in childhood are partially mediated by intersensory processing of audiovisual events in infancy

Socioeconomic status (SES) is a well-established predictor of individual differences in childhood language and cognitive functioning, including executive functions such as working memory. In infancy, intersensory processing—selectively attending to properties of events that are redundantly specified across the senses at the expense of non-redundant, irrelevant properties—also predicts language development. Our recent research demonstrates that individual differences in intersensory processing in infancy predict a variety of language outcomes in childhood, even after controlling for SES. However, relations among intersensory processing and cognitive outcomes such as working memory have not yet been investigated. Thus, the present study examines relations between intersensory processing in infancy and working memory in early childhood, and the role of SES in this relation. Children (N = 101) received the Multisensory Attention Assessment Protocol at 12-months to assess intersensory processing (face-voice and object-sound matching) and received the WPPSI at 36-months to assess working memory. SES was indexed by maternal education, paternal education, and income. A variety of novel findings emerged. 1) Individual differences in intersensory processing at 12-months predicted working memory at 36-months of age even after controlling for SES. 2) Individual differences in SES predicted intersensory processing at 12-months of age. 3) The well-established relation between SES and working memory was partially mediated by intersensory processing. Children from families of higher-SES have better intersensory processing skills at 12-months and this combination of factors predicts greater working memory two years later at 36-months. Together these findings reveal the role of intersensory processing in cognitive functioning.     

Bilingualism alters children's frontal lobe functioning for attentional control

Bilingualism is a typical linguistic experience, yet relatively little is known about its impact on children's cognitive and brain development. Theories of bilingualism suggest that early dual‐language acquisition can improve children's cognitive abilities, specifically those relying on frontal lobe functioning. While behavioral findings present much conflicting evidence, little is known about its effects on children's frontal lobe development. Using functional near‐infrared spectroscopy (fNIRS), the findings suggest that Spanish–English bilingual children (n = 13, ages 7–13) had greater activation in left prefrontal cortex during a non‐verbal attentional control task relative to age‐matched English monolinguals. In contrast, monolinguals (n = 14) showed greater right prefrontal activation than bilinguals. The present findings suggest that early bilingualism yields significant changes to the functional organization of children's prefrontal cortex for attentional control and carry implications for understanding how early life experiences impact cognition and brain development.