NGF and Mental deterioration: Reduced NE turnover has also been linked to cognitive decline in stress and hypoxia studies (Banderet and Lieberman, 1989; Deijen and Orlebeke, 1994) with NE concentration regulating BDNF and NGF expression (Bathina and Das, 2015; Chen et al., 2007; Aloe et al., 2015; Mandela and Ordway, 2006).