BDNF and dementia: For example, lower serum BDNF concentrations have been associated with an increased risk of incident dementia in subsets of older adults (Weinstein et al., 2014; Ng et al., 2019), and evidence from intervention studies have provided support for the hypothesis that aerobic exercise has a beneficial impact on executive function and may be mediated by an exercise-related increase in BNDF (Kramer et al., 1999; Erickson et al., 2012; de Assis and de Almondes, 2017).