雅思阅读

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The concept of neuroplasticity, once considered a fixed attribute of the developing brain, has revolutionized our understanding of adult cognition. Recent studies demonstrate that the adult brain retains the capacity to reorganize synaptic connections in response to learning or injury. This adaptability, however, is not uniform across all regions; the hippocampus, for instance, exhibits higher plasticity than the brainstem. Moreover, environmental enrichment and physical exercise have been shown to enhance neurogenesis in the dentate gyrus, a subregion of the hippocampus. Conversely, chronic stress and sleep deprivation can suppress this process, leading to cognitive decline. These findings suggest that cognitive health in adulthood is not merely a matter of genetic predisposition but is significantly influenced by lifestyle factors. Consequently, interventions aimed at promoting neuroplasticity may offer therapeutic potential for neurodegenerative diseases, although the precise molecular mechanisms remain under investigation.