The hippocampus is a brain structure that is important in consolidating memories, learning, and regulation of mood and behaviour; although the normal process of aging is associated with loss of hippocampal volume, there appear to be factors that speed the process including high levels of “oxidative stress and neuroinflammation, altered intracellular signaling and gene expression, [and] reduced neurogenesis and synaptic plasticity.” A team of researchers from British Columbia conducted a review of the current literature looking at the connection between these factors and the cognitive decline seen in aging. In their review of the current literature, they established that there are likely many different factors that contribute to the functional alterations that occur in the hippocampus with age, and many of these factors are preventable. In addition, normal cognitive decline involves similar changes as the decline seen in dementia, with the structural changes in dementia being much more pronounced due to presence of more severe inflammation and oxidative stress. In addition, dysregulated metabolic hormones (leptin and insulin) result in tau protein accumulation and amyloid plaques; this ultimately leads to impairment in the learning process. Interventions that implement healthy lifestyle such as diet, exercise, and cognitive stimulation have been shown to successfully decrease oxidative stress and protein buildup and protect hippocampal volume and cognitive function; in addition, these interventions have a synergistic effect, with multiple lifestyle interventions being additive in their effectiveness. Ultimately, much more research is warranted in this exciting field.
ORIGINAL ARTICLE: Science Direct: http://www.sciencedirect.com/science/article/pii/S0149763416307667
DATE RETRIEVED: May 5, 2017