The Aging Brain

Neurodegeneration is the progressive and gradual dysfunction and loss of axons in the central nervous system. It is the main pathological characteristic of chronic and acute neurodegenerative conditions like Alzheimer's disease (AD), Parkinson's disease (PD), and multiple sclerosis (MS). The usual aspects of pathogenesis of disease can be abridged with regards to the downstream implications of uncontrollable protein oligomerization and aggregation from postmitotic cells. The brain structure constantly changes in normal aging without any dysfunction accompanying the structural changes in brain. The decline in cognitive capabilities, for example, processing speed, memory, and functions related to decision making are the sign of healthy aging. The reduction in brain volume in healthy aging is possibly related to neuronal loss at some marginal extent. The following chapter discusses the structural and functional alterations in the brain in ageing and neurodegeneration.