Brain and Nerve最新文献

The development of human species-specific flexible cognitive and executive functions, particularly emotional control, determines lifelong mental and physical health. In this context, infancy and early childhood are sensitive periods, during which the environment dramatically alters the brain and gut. Since brain development related to emotional control is influenced by the gut microbiota, the development of interventional support methods from the perspective of brain-gut-gut microbiota interactions from an early age in life will lead to the creation of effective medical approaches that can prevent and alleviate future mental and physical disorders.

We can mentally simulate future possibilities and choose appropriate actions, even in situations that are completely novel. This flexible action selection involves introspection (metacognition) that is prominent in primates. I elucidated that flexible cognition in both social and non-social situations is enabled by an ability of prospective introspection (metacognition of the future). The process critically depends on the posterior inferior parietal lobule and the anterior lateral prefrontal area 47.

Decision-making requires flexibility and strategy. Imaging of single-cell-level neural activity and inhibition of neural activity in mice during a visual-discrimination learning task that requires a strategy revealed that dopamine D2 receptor-expressing medium-sized spiny neurons in the nucleus accumbens are important for flexible and strategic decision-making. Single-cell level imaging may be useful in understanding the pathophysiology of neuropsychiatric disorders that impair decision-making flexibility.

In everyday life, we routinely achieve overarching goals by assembling multiple sub-goals and flexibly switching between them. This ability, known as executive function, critically depends on the prefrontal cortex and is commonly divided into low- and high-order functions. In this article, we outline the framework of executive function and introduce recent animal studies that illuminate the neural mechanisms underlying higher-order executive functions.

The frontal lobe is involved in various aspects of behavioral expression and is one of the neural bases supporting flexible behavioral selection. Here, we consider six points: (1)the diversity of frontal lobe functions that support behavior, (2)flexible information representation at the cellular level, (3)representation of behavioral context by oscillatory states, (4)the scale-free nature of fluctuations in brain activity, and (5)the possibility of critical states at the cellular level seen in fluctuations and synchronization. Finally, we consider (6)the semiotic significance of the nervous system in cognition.

This paper provides a comprehensive review of the numerous discoveries derived from the dualistic perspective of cognition and emotion, while also discussing the limitations of this approach. Traditionally, emotion has been conceptualized using basic emotion and dimensional models, while cognition has been understood in terms of memory and decision-making. However, recent advances in neuroscience have demonstrated that emotion and cognition are interlinked and integrated into dynamic networks that form the basis of flexible behavior and intelligence. Based on these insights, there is a pressing need to redefine "intelligence" and develop a novel integrative model.

Multiple mechanisms are involved in flexible decision making, including relearning and the instantaneous switching of decisions depending on the environment. These mechanisms can be elucidated by integrating psychophysical, neurophysiological, and computational approaches. The flexibility of evidence accumulation necessary for instantaneous decision switching is supported by the mechanism of accumulating and discarding unnecessary information, which can be observed in the changes in decision-related activities in the LIP cortex as well as in other areas. The molecular mechanisms underlying the impairment of flexible decision-making are also discussed.

Memory bias is a tendency to encode and recall negative information preferentially and plays a critical role in the development and exacerbation of stress-related mental disorders. This review overviews the effectiveness and neurobiological mechanisms of a cognitive intervention to alleviate memory bias, 'memory bias modification,' based on the findings from previous studies and one of our recent randomized controlled trials.

Flexibility enables behaviors and thoughts to adapt to changing environments. The basal ganglia may play a critical role in the suppression and enhancement of flexibility by engaging in parallel and serial processing of several aspects of behavioral flexibility via afferent projections from related brain regions, such as the orbitofrontal cortex and intralaminar nucleus. Previous studies have suggested that the interactions between striatal cholinergic interneurons and these brain regions belong to a neuronal system that provides behavioral flexibility without interfering with existing learning and a new one regarding contingency, probably depending on glutaminergic and dopaminergic cholinergic inputs from the cerebral cortex, intralaminar nucleus, midbrain, and pedunculopontine nucleus. In particular, dorsomedial striatum cholinergic interneurons may exert bidirectional control of behavioral flexibility through neuronal dynamics among related brain areas that contribute to the cognitive subprocesses of flexibility.

Drug-induced parkinsonism (DIP) refers to a parkinsonian syndrome resulting from the use of drugs, such as antipsychotics, whose primary mechanism of action is dopamine receptor blockade. The clinical features of DIP typically include action tremors, muscular stiffness, slowness of movement, and postural instability, often with minimal lateral asymmetry. The diagnosis of DIP requires a thorough review of the patient's medication history and the exclusion of differential disorders, and the recommended management is discontinuation or dose reduction of the potentially causative agent. In patients with schizophrenia, switching the offending antipsychotic to another, preferably second-generation antipsychotic agent, is also recommended. This treatment strategy can be adapted to prevent DIP as well.