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1.
The effects of experimental lesions of the monkey prefrontal cortex have played a predominant role in current conceptualizations of the functional organization of the lateral prefrontal cortex, especially with regard to working memory. The loss or sparing of certain performance abilities has been shown to be attributable to differences in the specific requirements of behavioral testing (e.g., spatial vs. nonspatial memoranda) along with differences in the specific locations of applied ablations (e.g., dorsal vs. ventral prefrontal cortex). Such findings, which have accumulated now for over a century, have led to widespread acceptance that the dorsolateral and ventrolateral aspects of the prefrontal cortex may perform different, specialized roles in higher order cognition. Nonetheless, it remains unclear and controversial how the lateral prefrontal cortex is functionally organized. Two main views propose different types of functional specialization of the dorsal and ventral prefrontal cortex. The first contends that the lateral prefrontal cortex is segregated according to the processing of spatial and nonspatial domains of information. The second contends that domain specialization is not the key to the organization of the prefrontal cortex, but that instead, the dorsal and ventral prefrontal cortices perform qualitatively different operations. This report critically reviews all relevant monkey lesion studies that have served as the foundation for current theories regarding the functional organization of the prefrontal cortex. Our goals are to evaluate how well the existing lesion data support each theory and to enumerate caveats that must be considered when interpreting the relevant literature.  相似文献   

2.
Visual system has been proposed to be divided into two, the ventral and dorsal, processing streams. The ventral pathway is thought to be involved in object identification whereas the dorsal pathway processes information regarding the spatial locations of objects and the spatial relationships among objects. Several studies on working memory (WM) processing have further suggested that there is a dissociable domain-dependent functional organization within the prefrontal cortex for processing of spatial and nonspatial visual information. Also the auditory system is proposed to be organized into two domain-specific processing streams, similar to that seen in the visual system. Recent studies on auditory WM have further suggested that maintenance of nonspatial and spatial auditory information activates a distributed neural network including temporal, parietal, and frontal regions but the magnitude of activation within these activated areas shows a different functional topography depending on the type of information being maintained. The dorsal prefrontal cortex, specifically an area of the superior frontal sulcus (SFS), has been shown to exhibit greater activity for spatial than for nonspatial auditory tasks. Conversely, ventral frontal regions have been shown to be more recruited by nonspatial than by spatial auditory tasks. It has also been shown that the magnitude of this dissociation is dependent on the cognitive operations required during WM processing. Moreover, there is evidence that within the nonspatial domain in the ventral prefrontal cortex, there is an across-modality dissociation during maintenance of visual and auditory information. Taken together, human neuroimaging results on both visual and auditory sensory systems support the idea that the prefrontal cortex is organized according to the type of information being maintained in WM.  相似文献   

3.
赌博障碍是指持续且反复的赌博行为,给个人、家庭和社会都带来了严重后果,近年来受到越来越多研究者的关注。本研究总结了赌博障碍的认知功能缺陷及其神经基础,主要集中在如下四个方面:①认知扭曲、②奖赏和惩罚敏感性、③注意偏向和④决策。未来研究应多从认知神经科学角度深入探究赌博障碍的发生机制和发展过程,关注大脑结构变化及功能网络改变,并将其整合到一个统一的神经生物机制框架中,找到更加有效的干预和治疗手段。  相似文献   

4.
赌博障碍是指持续且反复的赌博行为,给个人、家庭和社会都带来了严重后果,近年来受到越来越多研究者的关注。本研究总结了赌博障碍的认知功能缺陷及其神经基础,主要集中在如下四个方面:①认知扭曲、②奖赏和惩罚敏感性、③注意偏向和④决策。未来研究应多从认知神经科学角度深入探究赌博障碍的发生机制和发展过程,关注大脑结构变化及功能网络改变,并将其整合到一个统一的神经生物机制框架中,找到更加有效的干预和治疗手段。  相似文献   

5.
朱海东  汪强 《心理科学》2015,(5):1095-1102
决策在人类社会发展的历程中扮演着非常重要的作用,而对其神经机制的探讨才不过几十年的时间。基于价值的决策理论,强调人们首先计算和表征事物的价值,随后比较和决策。在人脑中负责主观价值计算的神经基础有腹内侧前额叶皮层、眶额皮层以及其他脑区,而负责价值整合的脑区有腹内侧前额叶皮层、眶额皮层、背外侧前额叶皮层等。其中时间和风险的价值计算有着相同的神经基础,并且人脑可以将不同属性以及成本进行整合形成主观价值,按照曲线交互作用范式进行。通过自我控制、注意和认知调节等方法,同样可以调制人们的主观价值大小。未来需要继续强调模式分析、个体差异、老龄化和基因对价值计算的影响。  相似文献   

6.
This study used functional magnetic resonance imaging to identify the neural structures associated with women's underperformance on math tasks. Although women in a control condition recruited neural networks that are associated with mathematical learning (i.e., angular gyrus, left parietal and prefrontal cortex), women who were reminded of gender stereotypes about math ability did not recruit these regions, and instead revealed heightened activation in a neural region associated with social and emotional processing (ventral anterior cingulate cortex).  相似文献   

7.
爱荷华博弈任务(IGT)是一项检查情感性决策机制的常用实验范式。据此, Damasio等人提出了躯体标记假设(SMH)解释情绪影响决策的神经生理机制。近期, 大量研究在IGT究竟是模糊决策还是风险决策、与情绪和认知的关系、与工作记忆和陈述性记忆的关系以及IGT的神经网络与分子遗传机制等方面积累了丰富资料。结果显示, IGT加工的早期由模糊决策主导, 情绪性躯体信号对引导决策选项的偏好可能起关键作用, 后期则倾向是一种风险决策, 认知评价和预期对选项偏向逐渐占优势; IGT与工作记忆的加工成分有相互重叠, 也需陈述性记忆的参与; IGT的加工不仅依赖于杏仁核、腹内侧前额皮层、眶额皮层等组成的情绪脑网络的活动, 还与背外侧前额皮层、海马、腹侧纹状体、岛叶皮层、辅助运动前区、扣带回皮层等许多脑区的活动有关; COMT和5-HTT的基因多态性会调节IGT相关的决策加工。总之, IGT是一项需要多重神经系统协同活动的决策加工任务, 且模糊与风险决策可能具有不同的遗传基础。  相似文献   

8.
The most rapid physical and psychological growth occurs during adolescence, a period of transition from childhood to adulthood when the incidence of anxiety disorder peaks in humans. Human and animal studies suggest that dramatic changes in prefrontal cortical areas during adolescence are responsible for such prevalence of anxiety. Only recently, however, has the relationship between prefrontal immaturity and differential fear processing across adolescence been directly and systematically examined. Such progress is largely due to the culmination of rodent studies that delineated the fear learning, expression, and inhibition neural circuitry, and preclinical studies that provided avenues for translation. This article summarises those initial findings on the circuitry of fear inhibition, and describes in detail the new findings on adolescent fear inhibition that highlight the prefrontal cortex as a key, unrefined brain region that may govern adolescent vulnerability to anxiety disorders. Specifically, adolescent rodents have been demonstrated to be impaired in inhibiting learned fear responses following fear extinction due to prefrontal immaturity, a discovery that was shortly after replicated in adolescent humans (at least the behavioural component). Our desire for this article is to acquaint both research and clinical psychologists with the neural circuitry of fear learning and extinction, turn the attention to developmental work, and facilitate translation of preclinical rodent findings in humans.  相似文献   

9.
人类在社会互动中通过他人的行为对他人特质、意图及特定情境下的社会规范进行学习, 是优化决策、维护积极社会互动的重要条件。近年来, 越来越多的研究通过结合计算模型与神经影像技术对社会学习的认知计算机制及其神经基础进行了深入考察。已有研究发现, 人类的社会学习过程能够较好地被强化学习模型与贝叶斯模型刻画, 主要涉及的认知计算过程包括主观期望、预期误差和不确定性的表征以及信息整合的过程。大脑对这些计算过程的执行主要涉及奖惩加工相关脑区(如腹侧纹状体与腹内侧前额叶)、社会认知加工相关脑区(如背内侧前额叶和颞顶联合区)及认知控制相关脑区(如背外侧前额叶)。需要指出的是, 计算过程与大脑区域之间并不是一一映射的关系, 提示未来研究可借助多变量分析与脑网络分析等技术从系统神经科学的角度来考察大尺度脑网络如何执行不同计算过程。此外, 将来研究应注重生态效度, 利用超扫描技术考察真实互动下的社会学习过程, 并更多地关注内隐社会学习的计算与神经机制。  相似文献   

10.
Long‐term explicit memory is thought to involve a complex neural circuit including the medial temporal lobe, the medial diencephalon, the prefrontal cortex, and association cortices. When this memory system and associated neural circuitry develops is of great interest to developmental psychologists and developmental cognitive neuroscience researchers. In the present report, we provide evidence of a relation between behavioral and neurophysiological measures of long‐term explicit memory in 9‐month‐old infants. These measures provide converging evidence of the development of long‐term explicit memory at least by the end of the first year of life.  相似文献   

11.
Anxiety disorders are commonly treated with exposure-based therapies that rely on extinction of conditioned fear. Persistent fear and anxiety following exposure therapy could reflect a deficit in the recall of extinction learning. Animal models of fear learning have elucidated a neural circuit for extinction learning and recall that includes the amygdala, ventromedial prefrontal cortex (vmPFC), and hippocampus. Whereas the amygdala is important for extinction learning, the vmPFC is a site of neural plasticity that allows for the inhibition of fear during extinction recall. We suggest that the vmPFC receives convergent information from other brain regions, such as contextual information from the hippocampus, to determine the circumstances under which extinction or fear will be recalled. Imaging studies of human fear conditioning and extinction lend credence to this extinction network. Understanding the neural circuitry underlying extinction recall will lead to more effective therapies for disorders of fear and anxiety.  相似文献   

12.
认知行为疗法(CBT)是社交焦虑障碍的标准疗法,对其疗效的神经预测因子研究有利于个性化诊疗方案选择。初步证据表明,干预前高级视皮层、背侧前扣带回、背内/外侧前额叶及眶额皮层的功能激活,杏仁核与情绪调节相关脑区的结构与功能连接,情绪性刺激诱发的晚期正成分与治疗后症状的改善有关,因而是潜在的预测因子。基于机器学习的个体化预测存在样本量小的突出问题。未来研究应考虑跨研究机构合作共享大数据,在多模态、多任务条件下收集数据,并在独立样本中验证预测的有效性。  相似文献   

13.
Recently, there has been a convergence in lesion and neuroimaging data in the identification of circuits underlying positive and negative emotion in the human brain. Emphasis is placed on the prefrontal cortex (PFC) and the amygdala as two key components of this circuitry. Emotion guides action and organizes behavior towards salient goals. To accomplish this, it is essential that the organism have a means of representing affect in the absence of immediate elicitors. It is proposed that the PFC plays a crucial role in affective working memory. The ventromedial sector of the PFC is most directly involved in the representation of elementary positive and negative emotional states while the dorsolateral PFC may be involved in the representation of the goal states towards which these elementary positive and negative states are directed. The amygdala has been consistently identified as playing a crucial role in both the perception of emotional cues and the production of emotional responses, with some evidence suggesting that it is particularly involved with fear-related negative affect. Individual differences in amygdala activation are implicated in dispositional affective styles and increased reactivity to negative incentives. The ventral striatum, anterior cingulate and insular cortex also provide unique contributions to emotional processing.  相似文献   

14.
公平是人类社会生活的基本规范之一,不公平感及其相关决策则是研究者们关注的重要课题。长期以来,该领域的研究一般采用最后通牒博弈或其变式展开。大量脑成像研究探查了关于不公平感及相关决策的认知神经机制,尤其集中探讨了最后通牒博弈的回应者对不公平提议进行反应的脑区及其对应功能。经常得到关注的脑区包括了前脑岛、前扣带皮层、背外侧前额叶、内侧前额叶、杏仁核和颞顶交界等。对特殊人群的不公平感及相关决策进行研究可以帮助检验或澄清上述重要脑区及脑网络在不公平感及相关决策中扮演的角色,同时也阐释特殊人群的社会认知功能的特点。近年来,相当数量的研究关注了不同情境因素(包括分配方案相关因素和社会情境相关因素)调制不公平感及相关决策的过程,并讨论其背后的认知神经机制。未来的研究更应利用多模态数据分析方法,同时结合基因和激素层面的研究,以期深入对不公平感及相关决策的心理和生理机制的理解。  相似文献   

15.
This review provides a summary of the contributions made by human functional neuroimaging studies to the understanding of neural correlates of saccadic control. The generation of simple visually guided saccades (redirections of gaze to a visual stimulus or pro-saccades) and more complex volitional saccades require similar basic neural circuitry with additional neural regions supporting requisite higher level processes. The saccadic system has been studied extensively in non-human (e.g., single-unit recordings) and human (e.g., lesions and neuroimaging) primates. Considerable knowledge of this system’s functional neuroanatomy makes it useful for investigating models of cognitive control. The network involved in pro-saccade generation (by definition largely exogenously-driven) includes subcortical (striatum, thalamus, superior colliculus, and cerebellar vermis) and cortical (primary visual, extrastriate, and parietal cortices, and frontal and supplementary eye fields) structures. Activation in these regions is also observed during endogenously-driven voluntary saccades (e.g., anti-saccades, ocular motor delayed response or memory saccades, predictive tracking tasks and anticipatory saccades, and saccade sequencing), all of which require complex cognitive processes like inhibition and working memory. These additional requirements are supported by changes in neural activity in basic saccade circuitry and by recruitment of additional neural regions (such as prefrontal and anterior cingulate cortices). Activity in visual cortex is modulated as a function of task demands and may predict the type of saccade to be generated, perhaps via top-down control mechanisms. Neuroimaging studies suggest two foci of activation within FEF - medial and lateral - which may correspond to volitional and reflexive demands, respectively. Future research on saccade control could usefully (i) delineate important anatomical subdivisions that underlie functional differences, (ii) evaluate functional connectivity of anatomical regions supporting saccade generation using methods such as ICA and structural equation modeling, (iii) investigate how context affects behavior and brain activity, and (iv) use multi-modal neuroimaging to maximize spatial and temporal resolution.  相似文献   

16.
《Brain and cognition》2009,69(3):255-270
This review provides a summary of the contributions made by human functional neuroimaging studies to the understanding of neural correlates of saccadic control. The generation of simple visually guided saccades (redirections of gaze to a visual stimulus or pro-saccades) and more complex volitional saccades require similar basic neural circuitry with additional neural regions supporting requisite higher level processes. The saccadic system has been studied extensively in non-human (e.g., single-unit recordings) and human (e.g., lesions and neuroimaging) primates. Considerable knowledge of this system’s functional neuroanatomy makes it useful for investigating models of cognitive control. The network involved in pro-saccade generation (by definition largely exogenously-driven) includes subcortical (striatum, thalamus, superior colliculus, and cerebellar vermis) and cortical (primary visual, extrastriate, and parietal cortices, and frontal and supplementary eye fields) structures. Activation in these regions is also observed during endogenously-driven voluntary saccades (e.g., anti-saccades, ocular motor delayed response or memory saccades, predictive tracking tasks and anticipatory saccades, and saccade sequencing), all of which require complex cognitive processes like inhibition and working memory. These additional requirements are supported by changes in neural activity in basic saccade circuitry and by recruitment of additional neural regions (such as prefrontal and anterior cingulate cortices). Activity in visual cortex is modulated as a function of task demands and may predict the type of saccade to be generated, perhaps via top-down control mechanisms. Neuroimaging studies suggest two foci of activation within FEF - medial and lateral - which may correspond to volitional and reflexive demands, respectively. Future research on saccade control could usefully (i) delineate important anatomical subdivisions that underlie functional differences, (ii) evaluate functional connectivity of anatomical regions supporting saccade generation using methods such as ICA and structural equation modeling, (iii) investigate how context affects behavior and brain activity, and (iv) use multi-modal neuroimaging to maximize spatial and temporal resolution.  相似文献   

17.
Functional magnetic resonance imaging (fMRI) was used to study the neural correlates of neutral, stressful, negative and positive autobiographical memories. The brain activity produced by these different kinds of episodic memory did not differ significantly, but a common pattern of activation for different kinds of autobiographical memory was revealed that included (1) largely bilateral portions of the medial and superior temporal lobes, hippocampus and parahippocampus, (2) portions of the ventral, medial, superior and dorsolateral prefrontal cortex, (3) the anterior and posterior cingulate, including the retrosplenial, cortex, (4) the parietal cortex, and (5) portions of the cerebellum. The brain regions that were mainly activated constituted an interactive network of temporal and prefrontal areas associated with structures of the extended limbic system. The main bilateral activations with left-sided preponderance probably reflected reactivation of complex semantic and episodic self-related information representations that included previously experienced contexts. In conclusion, the earlier view of a strict left versus right prefrontal laterality in the retrieval of semantic as opposed to episodic autobiographical memory, may have to be modified by considering contextual variables such as task demands and subject variables. Consequently, autobiographical memory integration should be viewed as based on distributed bi-hemispheric neural networks supporting multi-modal, emotionally coloured components of personal episodes.  相似文献   

18.
物质成瘾与反转学习损伤密切相关,成瘾者往往不能灵活地适应变化的刺激—结果的联结,这可能进一步加剧成瘾者的物质使用。近年来研究发现,物质成瘾者的反转学习相关的腹外侧前额和背外侧前额等脑区激活异常,这些异常与成瘾者的冲动性和强迫性有关。此外,个体的反转学习能力对其成瘾行为具有一定预测性。今后应增加对不同类型物质成瘾者的反转学习脑机制及物质相关线索对成瘾者反转学习影响的研究,并且进一步探讨成瘾者的冲动性和强迫性对其反转学习的调节及个体反转学习能力对其成瘾行为的预测。  相似文献   

19.
The neural bases of inhibitory function are reviewed, covering data from paradigms assessing inhibition of motor responses (antisaccade, go/nogo, stop-signal), cognitive sets (e.g., Wisconsin Card Sort Test), and emotion (fear extinction). The frontal cortex supports performance on these paradigms, but the specific neural circuitry varies: response inhibition depends upon fronto-basal ganglia networks, inhibition of cognitive sets is supported by orbitofrontal cortex, and retention of fear extinction reflects ventromedial prefrontal cortex–amygdala interactions. Inhibition is thus neurobiologically heterogeneous, although right ventrolateral prefrontal cortex may support a general inhibitory process. Dysfunctions in these circuits may contribute to psychopathological conditions marked by inhibitory deficits.  相似文献   

20.
Previous investigations examining the rat prefrontal cortex subregions in attentional-set shifting have commonly employed two-choice discriminations. To better understand how varying levels of difficulty influence the contribution of the prefrontal cortex to learning, the present studies examined the effects of orbitofrontal cortex inactivation in a two- or four-choice odor reversal learning test. Long-Evans rats were trained to dig in cups that contained distinct odors. In the two-choice odor discrimination, one odor cup was always associated with a cereal reinforcement in acquisition while the opposite odor cup was associated with a cereal reinforcement in reversal learning. In the four-choice odor discrimination, an additional two cups containing distinct odors were used that were never associated with reinforcement in acquisition or reversal learning. Bilateral infusions of the GABA-A agonist, muscimol (0.5 microg) into the orbitofrontal cortex did not impair acquisition of either the two- or four-choice discrimination task. However, muscimol infusions into the orbitofrontal cortex impaired two- and four-choice reversal learning. In the two-choice odor reversal, muscimol treatment selectively increased perseverative errors. In the four-choice odor reversal, muscimol treatment increased perseverative, regressive, as well as irrelevant errors. These findings suggest that the orbital prefrontal cortex not only enables task switching by supporting the initial inhibition of a previously relevant choice pattern, but under increasing task demands also enables the reliable execution of a new choice pattern and reduction of interference to irrelevant stimuli.  相似文献   

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