Gregory D. Clemenson, Fred H. Gage, and Craig E.L. Stark
This chapter reviews the literature on environmental enrichment and specifically discusses its influence on the hippocampus of the brain. In animal models, the term “environmental enrichment” is used to describe a well-defined manipulation in which animals are exposed to a larger and more stimulating environment. This experience has been shown to have a powerful and positive impact on hippocampal cognition and neuroplasticity in animals. In humans, however, the translation of environmental enrichment is less clear. Despite the fact that humans live considerably more enriching lives compared to laboratory animals, studies have shown that training and expertise (such as exercise and spatial exploration) can lead to both functional and structural changes in the human brain. This chapter is a comprehensive review of environmental enrichment, drawing parallels between animal models and humans to present a more complete understanding of environmental enrichment.
Ramon Guirado and Eero Castrén
Neuronal networks are refined through an activity-dependent competition during critical periods of early postnatal development. Recent studies have shown that critical period plasticity is influenced by a number of environmental factors, including drugs that are widely used for the treatment of brain disorders. These findings suggest a new paradigm, where pharmacological treatments can be used to open critical period–like plasticity in the adult brain. The plastic networks can then be modified through rehabilitation or psychotherapy to rewire those abnormally wired during development. This kind of combination of pharmacotherapy with physical or psychological rehabilitation may open a new opportunity for a more efficient recovery of a number of neurological and neuropsychiatric disorders.