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1.
This paper argues that humans possess unique cognitive abilities due to the presence of a functional system that exists in the human brain that is absent in the non-human brain. This system, the frontal feedback system, was born in the hominin brain when the great phylogenetic expansion of the prefrontal cortex relative to posterior sensory regions surpassed a critical threshold. Surpassing that threshold effectively reversed the preferred direction of information flow in the highest association regions of the neocortex, producing the frontal feedback system. This reversal was from the caudo-rostral bias characteristic of non-human, or pre-human, brain dynamics to a rostro-caudal bias characteristic of modern human brain dynamics. The frontal feedback system works through frontal motor routines, or action schemes, manipulating the release and reconstruction of stored sensory memories in posterior sensory areas. As an obligatory feature of frontal feedback, a central character, or self, emerges within this cortical network that manifests itself as agent in these reconstructions as well as in the experience of sensory perceptions. Dynamical-systems modeling of cortical interactions is combined in the paper with recent neuroimaging studies of "resting-state" brain activity to bridge the gap between microscopic and macroscopic levels of cortical behavior. This synthesis is used to support the proposal of an information flow reversal occurring in the hominin brain and also to explain how such a reversal generates the wide variety of cognitive and experiential phenomena that many consider to be uniquely human.  相似文献   

2.
Abnormal decision making is a central feature of neuropsychiatric disorders. Recent investigations of the neural substrates underlying decision making have involved qualitative assessment of the cognition of decision making in clinical lesion studies (in patients with frontal lobe dementia) and neuropsychiatric disorders such as mania, substance abuse and personality disorders. A neural network involving the orbitofrontal cortex, ventral striatum and modulatory ascending neurotransmitter systems has been identified as having a fundamental role in decision making and in the neural basis of neuropsychiatric diseases. This network accounts for the dissociations among decision-making deficits in different clinical populations. Ultimately, a more refined and sophisticated characterization of such deficits might guide the early diagnosis and cognitive and therapeutic rehabilitation of these patients.  相似文献   

3.
In this reply, we endorse Chartrand's (2005) taxonomy of conscious awareness for different stages of consumer decisions affected by environmental cues. In addition, we attempt to broaden the scope of this taxonomy by discussing its usefulness for consumer decisions in general. We generally support Simonson's (2005) claim that research based on consumers as conscious decision makers is indeed predictive of a wide variety of behavior. However, we also argue that the importance of consciousness should not be overstated. Conscious processes observed in a research laboratory are not representative of conscious processes in real life. The alternative model to describe effects of the environment on behavior by Janiszewski and van Osselaer (2005) may be useful to explain automaticity in goal‐directed behavior, but it poorly describes other automatic behaviors.  相似文献   

4.
Computational models are tools for testing mechanistic theories of learning and development. Formal models allow us to instantiate theories of cognitive development in computer simulations. Model behavior can then be compared to real performance. Connectionist models, loosely based on neural information processing, have been successful in capturing a range of developmental phenomena, in particular on-line within-task category learning by young infants. Here we describe two new models. One demonstrates how age dependent changes in neural receptive field sizes can explain observed changes in on-line category learning between 3 and 10 months of age. The other aims to reconcile two conflicting views of infant categorization by focusing on the different task requirements of preferential looking and manual exploration studies. A dual-memory hypothesis posits that within-task category learning that drives looking time behaviors is based on a fast-learning memory system, whereas categorization based on background experience and assessed by paradigms requiring complex motor behavior relies on a second, slow-learning system. The models demonstrate how emphasizing the mechanistic causes of behaviors leads to discovery of deeper, more explanatory accounts of learning and development.  相似文献   

5.
Karl Ludwig Kahlbaum originally described catatonia as a psychomotor disease that encompassed motor, affective, and behavioral symptoms. In the beginning of the 20th century, catatonia was considered to be the motoric manifestation of schizophrenia; therefore, neuropathologic research mostly focused on neuroanatomic substrates (ie, the basal ganglia underlying the generation of movements). Even though some alterations were found in basal ganglia, the findings in these subcortical structures are not consistent. Recently, there has been a reemergence of interest into researching catatonia. Brain imaging studies have shown major and specific alterations in a right hemispheric neural network that includes the medial and lateral orbitofrontal and posterior parietal cortex. This neural network may be abnormally modulated by altered functional interactions between gamma-aminobutyric acid (GABA)-ergic and glutamatergic transmission. This may account for the interrelationship among motor, emotional, and behavioral alterations observed in both clinical phenomenology and the subjective experiences of patients with catatonia. Such functional interrelationships should be explored in further detail in catatonia, which may also serve as a paradigmatic model for the investigation of psychomotor and brain function in general.  相似文献   

6.
To determine if counselors integrate clinical behaviors for addressing religious/spiritual issues in counseling consistent with their ratings of the importance of such behaviors, the authors conducted a national survey of American Counseling Association (ACA) members. Seventy‐eight ACA members rated the importance of and frequency with which they engaged in a set of 30 clinical behaviors that were identified in the existing literature as addressing religious/spiritual issues within counseling. Results indicated possible disparities between importance and frequency ratings. Potential barriers to counselors' utilization of religious and spiritually directed clinical behaviors were identified.  相似文献   

7.
A new perspective on mental control is proposed that conceptually links conscious and automatic processes through a complementary postconscious activity that is rooted in the cognitive mechanism of priming. It is argued that the alterable structure of underlying mental representations connects these processes to produce a level of intentional regulation that would normally prove beneficial but in a few rare cases could prove detrimental. This hypothetical process is reflected in our empirical knowledge of mental control and related phenomena such as prospective memory. The new perspective maintains the traditional models' structure of conscious and automatic processing but, in an effort to expand our knowledge in the field, it redefines the relationship between these two processes so that it fits into a more accountable theoretical framework.  相似文献   

8.
Converging evidence indicates that repeated exposure to motor stimulants such as cocaine and amphetamine produces marked alterations in network responsiveness of striatal neurons to subsequent challenge with the same stimulant drug. Such alterations, which correlate with persistent patterns of repetitive behavior, associate with distinct compartmental changes in the neostriatum. Striatal matrix system neurons undergo "silencing" following repeated drug challenges, allowing striosome system neurons to exhibit preferential activation. Matrix neurons are innervated by sensory and motor areas of neocortex and are activated in the course of on-going, adaptive behavior. Inactivation of matrix neurons by chronic stimulant exposure may therefore constrain sensorimotor and cognitive processing. In turn, the striosomes are anatomically connected through re-entrant loops with limbic prefrontal and allocortical structures, such as anterior cingulate cortex, orbital frontal cortex, and basolateral amygdala, all of which play a part in stimulant-induced reinforcement and relapse to drug-taking. Moreover, functional evidence links striosome system neurons, which are responsible for providing inhibitory regulatory feedback to midbrain dopamine neurons, with reinforcement-based processes. In considering such evidence, we postulate that recurrent matrix inactivation and recruitment of striosome-based pathways by chronic stimulant exposure represent neural end-points of the transit from action-outcome associative behavior to conditioned habitual responding. Within this theoretical framework, habitual behavior can be elicited by both interoceptive cues and exteroceptive conditioned stimuli to promote the automatic execution of learned responses.  相似文献   

9.
The search for the neural substrates mediating the incremental acquisition of skilled motor behaviors has been the focus of a large body of animal and human studies in the past decade. Much less is known, however, with regard to the dynamic neural changes that occur in the motor system during the different phases of learning. In this paper, we review recent findings, mainly from our own work using fMRI, which suggest that: (i) the learning of sequential finger movements produces a slowly evolving reorganization within primary motor cortex (M1) over the course of weeks and (ii) this change in M1 follows more dynamic, rapid changes in the cerebellum, striatum, and other motor-related cortical areas over the course of days. We also briefly review neurophysiological and psychophysical evidence for the consolidation of motor skills, and we propose a working hypothesis of its underlying neural substrate in motor sequence learning.  相似文献   

10.
In a paradigm in which rats would both initiate and terminate hypothalamic stimulation, "purely" rewarding lateral hypothalamic and "purely" aversive medial hypothalamic electrodes were identified. Subjects were then given a series of tests designed to assess the effects of brain stimulation on approach and withdrawal behaviors. Lateral hypothalamic stimulation facilitated approach behavior and suppressed withdrawal behaviors, whereas medial hypothalamic stimulation produced largely the opposite effects. No serious motor deficits due to stimulation were detected with either type of electrode. In a second experiment, the approach-withdrawal effects of bilateral lateral hypothalamic lesions were tested and found to suppress approach behaviors and facilitate withdrawal behaviors. Other neurological examinations revealed motor deficits, but these deficits do not account for the specific pattern of results observed on the approach-withdrawal tests. These approach-withdrawal phenomena are interpreted in terms of altering a natural balance between approach and withdrawl behavior facilitating systems in the lateral and medial hypothalamus, respectively.  相似文献   

11.
To understand others’ minds is crucial for survival; however, it is quite puzzling how access to others’ minds can be—to some extent—direct and not necessarily mediated by conceptual reasoning. Recent advances in neuroscience have led to hypothesize a role for motor circuits not only in controlling the elementary physical features of movement (e.g., force, direction, and amplitude), but also in understanding and shaping human behavior. The concept of “motor cognition” refers to these aspects, and neurophysiological, neuroimaging, and behavioral studies in human and nonhuman primates support this view. From a clinical perspective, motor cognition represents a challenge in several domains. A thorough investigation of the neural mechanisms mediating motor action/intention understanding and automatized/compulsive behaviors seems to be a promising way to tackle a range of neurodevelopmental and drug-related disorders. On the one hand, anomalies in motor cognition may have cascade effects on social functioning in individuals with autism spectrum disorder (ASD); on the other, motor cognition may help explain the pathophysiology of drug-seeking and drug-taking behaviors in the most severe phase of drug addiction (i.e., see drug dependence, motor low-order cue reactivity). This may represent a promising approach that could improve the efficacy of rehabilitative interventions. The only way to shed light on multifactorial disorders such as ASD and drug addiction is through the investigation of their multiple factors. This motor way can promote new theoretical and experimental perspectives that would help bridge the gap between the basic neuroscience approach and clinical practice.  相似文献   

12.
The aim of this research was to study the effect of 12-minute clinical death on innate and acquired behavior, biogenic amine concentration, and the composition and quantity of neural populations in specific brain regions of white rats. The study shows that in animals during the postresuscitation period with formal restoration of neurological status, there are changes in emotional reactivity, orientation-exploration reactions, impairment of learning and memory, decrease in exercise tolerance and pain sensitivity. These processes are accompanied by alterations in serotonin and norepinephrine levels in the frontal cerebral cortex, dopamine and serotonin levels in the striatum, certain biochemical indices in blood plasma and neural loss in the CA1 sector of the hippocampus and lateral portions of the cerebellum.  相似文献   

13.
运动表象质量与运动技能水平有关,运动表象质量随着运动技能水平的提高而上升。器械使用可使人脑产生可塑性改变,使用者会将器械纳入身体图式。然而,两者影响运动表象的神经心理机制还不清楚。本研究采用功能性磁共振成像探析篮球运动员与新手在不同持球条件下表象投篮时脑功能活动的差异。结果表明运动员表象质量较好,镜像神经系统激活高于新手;持球条件下运动员表象质量显著高于不持球条件下,镜像神经系统激活程度显著低于不持球条件下。研究说明持器械可以显著提高运动员的表象质量,器械使用带来镜像神经系统的可塑性变化。  相似文献   

14.
空气污染对行为影响的研究日渐丰富, 且大致分为两个方向:一是与环境健康有关的直接行为, 二是与之无直接相关的社会行为(溢出行为)。基于此, 在回顾空气污染对两种行为影响研究的同时, 进一步综述了用于解释直接行为产生机制的计划行为理论和健康行动过程取向模型, 以及用于解释社会行为机制的焦虑与自我损耗。而更全面的探究现象背后的机制有助于发现更多有效应对空气污染的举措, 未来的研究可以采用更多纵向的研究范式、增加对行为机制的探究, 从而改善人们的风险应对行为。  相似文献   

15.
The current paper shows a neuro-robotics experiment on developmental learning of goal-directed actions. The robot was trained to predict visuo-proprioceptive flow of achieving a set of goal-directed behaviors through iterative tutor training processes. The learning was conducted by employing a dynamic neural network model which is characterized by their multiple time-scale dynamics. The experimental results showed that functional hierarchical structures emerge through stages of developments where behavior primitives are generated in earlier stages and their sequences of achieving goals appear in later stages. It was also observed that motor imagery is generated in earlier stages compared to actual behaviors. Our claim that manipulatable inner representation should emerge through the sensory–motor interactions is corresponded to Piaget’s constructivist view.  相似文献   

16.
Neuropsychology of timing and time perception   总被引:1,自引:0,他引:1  
Interval timing in the range of milliseconds to minutes is affected in a variety of neurological and psychiatric populations involving disruption of the frontal cortex, hippocampus, basal ganglia, and cerebellum. Our understanding of these distortions in timing and time perception are aided by the analysis of the sources of variance attributable to clock, memory, decision, and motor-control processes. The conclusion is that the representation of time depends on the integration of multiple neural systems that can be fruitfully studied in selected patient populations.  相似文献   

17.
ABSTRACT

Increasingly, informal science and environmental education institutions are addressing conservation messaging and environmental behavior in programming, exhibits, and interpretation. Yet, little is known about what pro-environmental behaviors visitors are currently undertaking, what characteristics those environmental behaviors may have in common, and what differences might exist among visitor populations. This study investigated environmental behaviors and attitudes of visitors (N = 689) to an informal science museum, including separate foci on members and nonmembers based on previous work suggesting differences between the two groups. To improve research, policy, and educational interventions that address environmental behavior, researchers have long sought to uncover relationships among unique environmental behaviors. To this end, the authors explored whether five commonly recommended pro-environmental behaviors shared underlying characteristics that could be used to group those behaviors. They uncovered some dissimilarity in self-reported environmental behaviors among members and nonmembers. Although no single shared construct underlying the behaviors was evident, the authors did find, for nonmember visitors, a suite of three traditional environmental behaviors and, for members, a suite of four contemporary environmental behaviors. They discuss implications for practice and future research.  相似文献   

18.
跨期决策是指人们对时间成本与收益进行权衡, 进而做出评价与选择, 其研究主要围绕时间折扣, 是指与当前或近期的损益相比, 人们赋予未来损益更小的权重。虽然有争议, 但Mischel等人很早就通过著名的“棉花糖实验”证明了延迟满足能力越强的儿童有着更高的学业成就。延迟满足与跨期决策都是在时间维度上进行的决策。研究者通过脑成像技术发现了成人大脑内支持跨期决策的三个神经网络系统, 但关于儿童的研究鲜有报道。这三大脑网络系统都位于额叶皮层, 该皮层在儿童青少年时期快速发育。通过采用横断研究和纵向研究相结合的实验设计, 对处于跨期决策发展关键期的中国儿童青少年人群进行测查和追踪; 借助神经影像技术, 考察跨期决策发展与脑发育的关系; 整合多模态神经影像技术, 构建可以预测跨期决策能力的脑影像指标。  相似文献   

19.
Violence is a major problem in our society and therefore research into the neural underpinnings of aggression has grown exponentially. Although in the past decade the biological underpinnings of aggressive behavior have been examined, research on neural oscillations in violent offenders during resting-state electroencephalography (rsEEG) remains scarce. In this study we aimed to investigate the effect of high-definition transcranial direct current stimulation (HD-tDCS) on frontal theta, alpha and beta frequency power, asymmetrical frontal activity, and frontal synchronicity in violent offenders.Fifty male violent forensic patients diagnosed with a substance dependence were included in a double-blind sham-controlled randomized study. The patients received 20 minutes of HD-tDCS two times a day on five consecutive days. Before and after the intervention, the patients underwent a rsEEG task.Results showed no effect of HD-tDCS on the power in the different frequency bands. Also, no increase in asymmetrical activity was found. However, we found increased synchronicity in frontal regions in the alpha and beta frequency bands indicating enhanced connectivity in frontal brain regions as a result of the HD-tDCS-intervention.This study has enhanced our understanding of the neural underpinnings of aggression and violence, pointing to the importance of alpha and beta frequency bands and their connectivity in frontal brain regions. Although future studies should further investigate the complex neural underpinnings of aggression in different populations and using whole-brain connectivity, it can be suggested with caution, that HD-tDCS could be an innovative method to regain frontal synchronicity in neurorehabilitation.  相似文献   

20.
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   

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