The Aging Brain: A Neuropsychological Perspective on Cognitive Decline

Aging represents a progressively increasing phenomenon that has collaterally increased the prevalence of neurodegenerative diseases. Objective: The present review has proposed to analyze, through the updated scientific bibliography, the main factors related to both normal and pathological aging around the world, systematizing the main findings as revealed from neuroscience. Methods: Systematic search of scientific literature published in the last decade from the Web of Science, Scopus, and PubMed. Results: The literature describes various highly reduced brain structures and functions in healthy older adults and those diagnosed with dementia; particularly prefrontal, parietal, temporo-hippocampal, dorsolateral regions, and cingulate cortex. In addition, patterns of white matter degradation, demyelination, and cholinergic, dopaminergic, and serotonergic conditions are reported. Neurobiological, genetic and environmental models coincide with the participation of specific markers such as amyloidal deposits, neurofibrillary tangles and microglial inflammation as gold standard elements in the diagnosis of normative aging and dementia related deterioration of the neuronal functions of the elderly, which in turn would respond to apoptotic predispositions and metabolic oxidation processes by free radicals. Conclusions: The scientific community sustains that the earlier an individual begins to promote prevention strategies in favor of cognitive reserve and neuroplasticity, the less likely they are to experience the patterns and consequences of cognitive impairment due to neurodegeneration. A high cognitive reserve therefore seems to act as a neuroprotective variable against the onset and development of disorders such as Alzheimer's.