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1.
Our knowledge of the human brain has increased more during the past 40 years than at any other time in history. Of particular interest have been the findings of a correspondence between cognitive functions and individual structures of the brain. Similar from a gross anatomical point of view, the hemispheres of the brain have been shown to serve specialized cognitive functions. This work offers an overview of the cognitive aspects of cerebral lateralization as a context for considering this issue, followed by a review of specific self-report techniques in the appraisal of lateral preference.  相似文献   

2.
We selectively review the progress of research on the psychology of time during the past 125 years, starting with the publication of the first English-language psychological journal, The American Journal of Psychology. A number of important articles on the psychology of time appeared in this journal, including the widely cited early article by Nichols (1891). The psychology of time is a seminal topic of psychological science, and although it entered a phase of decline and even moribund neglect, the past several decades have seen a prominent renaissance of interest. This renewed vigor represents the rebirth of the recognition of the centrality of the psychology of time in human cognition and behavior. Our selective overview highlights a number of strands of progress and how they have helped lead to the present, in which the cognitive neuroscience of time and timing in the brain is one of the most fervent and fertile modern areas of brain research. We also discuss some remaining challenges and potential lines of progress.  相似文献   

3.
Schizophrenia—a severe psychiatric condition characterized by hallucinations, delusions, loss of initiative and cognitive function—is hypothesized to result from abnormal anatomical neural connectivity and a consequent decoupling of the brain’s integrative thought processes. The rise of in vivo neuroimaging techniques has refueled the formulation of dysconnectivity hypotheses, linking schizophrenia to abnormal structural and functional connectivity in the brain at both microscopic and macroscopic levels. Over the past few years, advances in high-field structural and functional neuroimaging techniques have made it increasingly feasible to reconstruct comprehensive maps of the macroscopic neural wiring system of the human brain, know as the connectome. In parallel, advances in network science and graph theory have improved our ability to study the spatial and topological organizational layout of such neural connectivity maps in detail. Combined, the field of neural connectomics has created a novel platform that provides a deeper understanding of the overall organization of brain wiring, its relation to healthy brain function and human cognition, and conversely, how brain disorders such as schizophrenia arise from abnormal brain network wiring and dynamics. In this review we discuss recent findings of connectomic studies in schizophrenia that examine how the disorder relates to disruptions of brain connectivity.  相似文献   

4.
In the past few years connectionist models have greatly contributed to formulating theories of cognitive development. Some of these models follow the approach of developmental cognitive neuroscience in exploring interactions between brain development and cognitive development by integrating structural change into learning. We describe two classes of these models. The first focuses on experience-dependent structural elaboration within a brain region by adding or deleting units and connections during learning. The second models the gradual integration of different brain areas based on combinations of experience-dependent and maturational factors. These models provide new theories of the mechanisms of cognitive change in various domains and they offer an integrated framework to study normal and abnormal development, and normal and impaired adult processing.  相似文献   

5.
对语言神经机制的新认识   总被引:5,自引:0,他引:5  
周昌乐  唐孝威 《心理科学》2001,24(4):396-401
本文针对语言神经机制的研究现状,分析了失语症和裂脑人研究的成果,并且较为详细地介绍了最近十年脑功能成像得到的有关语言神经活动的新成就,在此基础上,提出了一种动态分布式竞争的解释理论,用来解释语言神经活动现象和规律,并进一步借以说明言语意识的产生机制。  相似文献   

6.
Motor development in very preterm children differs in several important ways from that of children born at full term. Variability is common, although the anatomic and physiologic bases for that variability are often poorly understood. Motor patterns over the first postnatal year may depend on behaviours learned during often long periods of neonatal intensive care. The normal pattern of development may be modified by disturbances of brain function caused both by the interruption of normal brain maturation ex-utero and the superimposition of focal brain injuries following very preterm birth. Abnormal patterns of development over the first year may evolve into clear neuromotor patterns of cerebral palsy or resolve, as "transient dystonias." Cerebral palsy is associated with identified patterns of brain injury secondary to ischaemic or haemorrhagic lesions, perhaps modified by activation of inflammatory cytokines. Cerebral palsy rates have not fallen as might be expected over the past 10 years as survival has improved, perhaps because of increasing survival at low gestations, which is associated with the highest prevalence of cerebral palsy. Children who escape cerebral palsy are also at risk of motor impairments during the school years. The relationship of these impairments to perinatal factors or to neurological progress over the first postnatal year is debated. Neuromotor abnormalities are the most frequent of the "hidden disabilities" among ex-preterm children and are thus frequently associated with poorer cognitive ability and attention deficit disorders. Interventions to prevent cerebral palsy or to reduce these late disabilities in very preterm children are needed.  相似文献   

7.
语音在汉字语义通达中的作用是二十多年来心理语言学研究的热点之一。直通假设和形音交互假设是学者们主张的理论观点,它们在语音和语义的相互关系上存在分歧,并分别有各自的实验证据。从比较语音语义激活时间进程、同音字效应、神经心理学与脑成像、语音作用的发展转换这四个方面对过去的研究进行回顾,指出了实验范式和实验材料中存在的问题,并提出结合汉字特点进行研究的思路。  相似文献   

8.
Non-linear changes in behaviour and in brain activity during adolescent development have been reported in a variety of cognitive tasks. These developmental changes are often interpreted as being a consequence of changes in brain structure, including non-linear changes in grey matter volumes, which occur during adolescence. However, very few studies have attempted to combine behavioural, functional and structural data. This multi-method approach is the one we took in the current study, which was designed to investigate developmental changes in behaviour and brain activity during relational reasoning, the simultaneous integration of multiple relations. We used a relational reasoning task known to recruit rostrolateral prefrontal cortex (RLPFC), a region that undergoes substantial structural changes during adolescence. The task was administered to female participants in a behavioural (N = 178, 7-27 years) and an fMRI study (N = 37, 11-30 years). Non-linear changes in accuracy were observed, with poorer performance during mid-adolescence. fMRI and VBM results revealed a complex picture of linear and possibly non-linear changes with age. Performance and structural changes partly accounted for changes with age in RLPFC and medial superior frontal gyrus activity but not for a decrease in activation in the anterior insula/frontal operculum between mid-adolescence and adulthood. These functional changes might instead reflect the maturation of neurocognitive strategies.  相似文献   

9.
In the past few decades, neuroscience research has greatly expanded our understanding of how the human brain functions. In particular, we have begun to explore the basis of emotions, intelligence, and creativity. These brain functions also have been applied to various aspects of behavior, thought, and experience. We have also begun to develop an understanding of how the brain and mind work during aesthetic and religious experiences. Studies on these topics have included neuropsychological tests, physiological measures, and brain imaging. These different techniques have enabled us to open up a window into the brain. It is by understanding the functioning of the creative brain that we begin to understand the concept of the creative mind. It is through the use of emotions and other higher cognitive functions that the brain and mind can create ideas, music, literature, and ultimately our entire repertoire of behaviors. How these different creative abilities are derived can also be traced to various parts of the brain and how they function. Modern neuroscience allows us to begin to understand the creative aspect of the brain and mind and perhaps can take us one step further toward understanding the most profound types of aesthetic and religious experiences.  相似文献   

10.
Motivated by specialization (lateralization) that occurs in corresponding left and right regions of the cerebral cortex, several past computational models have studied conditions under which functional specialization can arise during learning due to underlying asymmetries in paired neural networks. However, these past studies have not addressed the basic issue of how such underlying asymmetries arise in the first place. As an initial step in addressing this issue, we investigated the hypothesis that underlying asymmetries will appear in paired neural networks during a simulated evolutionary process when fitness is based not only on maximizing performance, but also on minimizing various ‘costs’ such as energy consumption, neural connection weights, and response times. Simulated evolution under these conditions consistently produced networks with left–right asymmetries in region size, excitability and plasticity. These underlying asymmetries were often synergistic, leading to subsequent functional lateralization during network training. While our computational models are too simple for these results to be directly extrapolated to real nervous systems, they provide support for the hypothesis that brain asymmetries and lateralization in biological nervous systems may be a consequence of cost minimization present during evolution, and are the first computational demonstration of emergent population lateralization.  相似文献   

11.
Lyman A. Page 《Zygon》2007,42(3):767-778
Progress in technology has allowed dynamic research on the development of the human brain that has revolutionized concepts. Particularly, the notions of plasticity, neuronal selection, and the effects of afferent stimuli have entered into thinking about brain development. Here I focus on development from the age of four years to early adulthood, during which a 30 percent reduction in some brain synapses occurs that is out of proportion to changes in neuronal numbers. This corresponds temporally with changes in normal child behavior from the loose‐associative, almost schizoid, thinking and art of the four‐year‐old to the more trained, or disciplined, or acculturated—and restrained—personality of the young adult. I propose that the synaptic changes can best be thought of as a winnowing process likely subject to environmental influences. Acquisition of language and the ability to link linguistic cognition to the plastic development of the brain provide a potentially powerful means of explaining the evolutionally explosive development of human cognition and culture. Schizophrenia, a disease that can be envisioned as representing a derangement of synaptic maturation, may provide an entry into the search for genes controlling the processes mediating the unprecedented development of Homo sapiens over the past 40,000 to 70,000 years. The recently completed mapping of the genome of the chimpanzee provides a new frame of reference that may speed the search.  相似文献   

12.
Adolescence is usually defined as the period of psychological and social transition between childhood and adulthood. The beginning of adolescence, around the onset of puberty, is characterized by large hormonal and physical changes. The transition from childhood to adulthood is also characterized by psychological changes in terms of identity, self-consciousness, and cognitive flexibility. In the past decade, it has been demonstrated that various regions of the human brain undergo development during adolescence and beyond. Some of the brain regions that undergo particularly protracted development are involved in social cognitive function in adults. In the first section of this paper, I briefly describe evidence for a circumscribed network of brain regions involved in understanding other people. Next, I describe evidence that some of these brain regions undergo structural development during adolescence. Finally, I discuss recent studies that have investigated social cognitive development during adolescence.  相似文献   

13.
Contrary to assumptions that changes in brain networks are possible only during crucial periods of development, research in the past decade has supported the idea of a permanently plastic brain. Novel experience, altered afferent input due to environmental changes and learning new skills are now recognized as modulators of brain function and underlying neuroanatomic circuitry. Given findings in experiments with animals and the recent discovery of increases in gray and white matter in the adult human brain as a result of learning, the old concept of cognitive reserve, that is the ability to reinforce brain volume in crucial areas and thus provide a greater threshold for age-dependent deficits, has been reinforced. The challenge we face is to unravel the exact nature of the dynamic structural alterations and, ultimately, to be able to use this knowledge for disease management. Understanding normative changes in brain structure that occur as a result of environmental changes and demands is pivotal to understanding the characteristic ability of the brain to adapt.  相似文献   

14.
The past few years have seen considerable interest in findings of abnormal brain connectivity in the autism spectrum disorders (ASD). We review recent work from neuroimaging and other sources, and argue that there is considerable convergent evidence suggesting that connectivity is disrupted in ASD. We point to evidence both of local over-connectivity and of long-distance under-connectivity, and describe some non-uniformities in this picture, most notably that disruptions appear more severe in later-developing cortical regions. We conclude by discussing a number of extant questions. Firstly, we consider whether aberrant connectivity should be seen as part of the primary pathogenesis of autism, or whether disrupted connectivity in ASD emerges over time. Secondly, we consider how the patterns of disrupted connectivity found in ASD might relate to those being found in a range of other disorders.  相似文献   

15.
This paper discusses how the understanding of autism has changed in the 60 years since Leo Kanner first described the syndrome. Originally identified as an emotional disorder caused by parental ambivalence and rejection, autism today is universally seen as a neurohiological difficulty, whose cause is organic and related to atypical brain development. Evidence for the organic and genetic causes is presented, along with a discussion of how the understanding of autism has evolved during the past half century. The current understanding of autism as a developmental disorder has dramatically improved the quality of care and effectiveness of interventions for these youngsters and their families.  相似文献   

16.
The brain's histaminergic system has been implicated in hippocampal synaptic plasticity, learning, and memory, as well as brain reward and reinforcement. Our past pharmacological and lesion studies indicated that the brain's histamine system exerts inhibitory effects on the brain's reinforcement respective reward system reciprocal to mesolimbic dopamine systems, thereby modulating learning and memory performance. Given the close functional relationship between brain reinforcement and memory processes, the total disruption of brain histamine synthesis via genetic disruption of its synthesizing enzyme, histidine decarboxylase (HDC), in the mouse might have differential effects on learning dependent on the task-inherent reinforcement contingencies. Here, we investigated the effects of an HDC gene disruption in the mouse in a nonreinforced object exploration task and a negatively reinforced water-maze task as well as on neo- and ventro-striatal dopamine systems known to be involved in brain reward and reinforcement. Histidine decarboxylase knockout (HDC-KO) mice had higher dihydrophenylacetic acid concentrations and a higher dihydrophenylacetic acid/dopamine ratio in the neostriatum. In the ventral striatum, dihydrophenylacetic acid/dopamine and 3-methoxytyramine/dopamine ratios were higher in HDC-KO mice. Furthermore, the HDC-KO mice showed improved water-maze performance during both hidden and cued platform tasks, but deficient object discrimination based on temporal relationships. Our data imply that disruption of brain histamine synthesis can have both memory promoting and suppressive effects via distinct and independent mechanisms and further indicate that these opposed effects are related to the task-inherent reinforcement contingencies.  相似文献   

17.
Over the past several years, drug addiction has increasingly been accepted to be a disease of the brain as opposed to simply being due to a lack of willpower or personality flaw. Exposure to addictive substances has been shown to create enduring changes in brain structure and function that are thought to underlie the transition to addiction. Specific genetic and environmental vulnerability factors also influence the impact of drugs of abuse on the brain and can enhance the likelihood of becoming an addict. Long-lasting alterations in brain function have been found in neural circuits that are known to be responsible for normal appetitive learning and memory processes and it has been hypothesized that drugs of abuse enhance positive learning and memory about the drug while inhibiting learning about the negative consequences of drug use. Therefore, the addict's behavior becomes increasingly directed towards obtaining and using drugs of abuse, while at the same time developing a poorer ability to stop using, even when the drug is less rewarding or interferes with functioning in other facets of life. In this review we will discuss the clinical evidence that addicted individuals have altered learning and memory and describe the possible neural substrates of this dysfunction. In addition, we will explore the pre-clinical evidence that drugs of abuse cause a progressive disorder of learning and memory, review the molecular and neurobiological changes that may underlie this disorder, determine the genetic and environmental factors that may increase vulnerability to addiction, and suggest potential strategies for treating addiction through manipulations of learning and memory.  相似文献   

18.
Change blindness   总被引:1,自引:0,他引:1  
Although at any instant we experience a rich, detailed visual world, we do not use such visual details to form a stable representation across views. Over the past five years, researchers have focused increasingly on 'change blindness' (the inability to detect changes to an object or scene) as a means to examine the nature of our representations. Experiments using a diverse range of methods and displays have produced strikingly similar results: unless a change to a visual scene produces a localizable change or transient at a specific position on the retina, generally, people will not detect it. We review theory and research motivating work on change blindness and discuss recent evidence that people are blind to changes occurring in photographs, in motion pictures and even in real-world interactions. These findings suggest that relatively little visual information is preserved from one view to the next, and question a fundamental assumption that has underlain perception research for centuries: namely, that we need to store a detailed visual representation in the mind/brain from one view to the next.  相似文献   

19.
One of the most common questions we get asked as historians of psychiatry is “do you have access to patient records?” Why are people so fascinated with the psychiatric patient record? Do people assume they are or should be available? Does access to the patient record actually tell us anything new about the history of psychiatry? And if we did have them, what can, or should we do with them? In the push to both decolonize and personalize the history of psychiatry, as well as make some kind of account or reparation for past mistakes, how can we proceed in an ethical manner that respects the privacy of people in the past who never imagined their intensely personal psychiatric encounter as subject for future historians? In this paper, we want to think through some of the issues that we deal with as white historians of psychiatry especially at the intersection of privacy, ethics, and racism. We present our thoughts as a conversation, structured around questions we have posed for ourselves, and building on discussions we have had together over the past few years. We hope that they act as a catalyst for further discussion in the field.  相似文献   

20.
The preschool years represent a time of expansive mental growth, with the initial expression of many psychological abilities that will continue to be refined into young adulthood. Likewise, brain development during this age is characterized by its ??blossoming?? nature, showing some of its most dynamic and elaborative anatomical and physiological changes. In this article, we review human brain development during the preschool years, sampling scientific evidence from a variety of sources. First, we cover neurobiological foundations of early postnatal development, explaining some of the primary mechanisms seen at a larger scale within neuroimaging studies. Next, we review evidence from both structural and functional imaging studies, which now accounts for a large portion of our current understanding of typical brain development. Within anatomical imaging, we focus on studies of developing brain morphology and tissue properties, including diffusivity of white matter fiber tracts. We also present new data on changes during the preschool years in cortical area, thickness, and volume. Physiological brain development is then reviewed, touching on influential results from several different functional imaging and recording modalities in the preschool and early school-age years, including positron emission tomography (PET), electroencephalography (EEG) and event-related potentials (ERP), functional magnetic resonance imaging (fMRI), magnetoencephalography (MEG), and near-infrared spectroscopy (NIRS). Here, more space is devoted to explaining some of the key methodological factors that are required for interpretation. We end with a section on multimodal and multidimensional imaging approaches, which we believe will be critical for increasing our understanding of brain development and its relationship to cognitive and behavioral growth in the preschool years and beyond.  相似文献   

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