Environmental Factors Promoting Neural Plasticity: Insights from Animal and Human Studies

Abstract

We do not all grow older in the same way. Some individuals have a cognitive decline earlier and faster than others who are older in years but cerebrally younger. This is particularly easy to verify in people who have maintained regular physical activity and healthy and cognitively stimulating lifestyle and even in the clinical field. There are patients with advanced neurodegeneration, such as Alzheimer's disease (AD), that, despite this, have mild cognitive impairment. What determines this interindividual difference? Certainly, it cannot be the result of only genetic factors. We are made in a certain manner and what we do acts on our brain. In fact, our genetic basis can be modulated, modified, and changed by our experiences such as education and life events; daily, by sleep schedules and habits; or also by dietary elements. And this can be seen as true even if our experiences are indirectly driven by our genetic basis. In this paper, we will review some current scientific research on how our experiences are able to modulate the structural organization of the brain and how a healthy lifestyle (regular physical activity, correct sleep hygiene, and healthy diet) appears to positively affect cognitive reserve.

Pregnancy and adolescence entail similar neuroanatomical adaptations: A comparative analysis of cerebral morphometric changes

“…Likewise, the effect of sex steroid hormones on brain structure has also been documented in studies tracking menstrual cycles (Protopopescu et al, 2008) and menopause (Eberling et al, 2003), The integration of our findings with the above literature leads us to consider that sex steroid hormones are the main mediators of the observed morphometric changes. Nonetheless, brain plasticity can also be induced by environmental signals that alter the body homeodynamics (Mandolesi et al, 2017). Indeed, in rodent and primate species, the emergence of maternal behavior is stimulated not only by the array of endocrine changes accompanying gestation but also by environmental cues coming from the offspring (Numan, 2007;Numan & Woodside, 2010).…”

Effects of Physical Exercise on Cognitive Functioning and Wellbeing: Biological and Psychological Benefits

“…In animal studies, the structural changes analyzed concern the cellular (neurogenesis, gliogenesis, synaptogenesis, angiogenesis) and molecular (alteration in neurotransmission systems and increasing in some neurotrophic factors) level (Gelfo et al, 2018 ), while the functional activity has been measured using the levels of performance in behavioral tasks, such as spatial tasks that allow to analyze the different facets of spatial cognitive functions (Mandolesi et al, 2017 ). In humans, indicators of structural changes correspond for example to brain volumes, measures of white matter integrity or modulation in neurotrophins levels (by correlation with trophic factors plasma levels).…”

“…Such metrics can be correlated to cognitive performances, defining the functional neural efficiency (Serra et al, 2011 ). To this regard, it should be emphasized that any morphological change results in a modification of the functional properties of a neural circuit and vice versa any change in neuronal efficiency and functionality is based on morphological modifications (Mandolesi et al, 2017 ).…”

Feasibility of a Functional Medicine Approach to Slowing Clinical Cognitive Decline in Patients over Age 55: A Multiple Case Study Report

“…And in 2018, Bredesen reported improved clinical outcomes for 100 patients following the MEND protocol [3]. Further, the literature is rife with current research addressing the need for and efficacy of non-pharmaceutical interventions for targeting cognitive decline such as physical activity, ample sleep, and healthy diet [11][12][13][14][15]. Coupled with the new AAN recommendations for treating MCI, medical practitioners are moving away from prescription drug treatment and are now considering cognitive training along with modification of such lifestyle variables [2,16].…”