“…The principal types of mental health outcomes reported in previous studies include: improved attention (Tennessen and Cimprich, 1995;Faber and Kuo, 2011); changed attitudes (Weinstein et al, 2009); improved cognition (Berman et al, 2008(Berman et al, , 2012Bratman et al, 2012;Wu et al, 2014;Zedelius and Schooler, 2015); reduced levels of stress, anxiety, and depression (Nutsford et al, 2013;Bratman et al, 2015); reduced use of antidepressants (Hartig et al, 2007;Taylor et al, 2015); improved recovery from stress (Bodin and Hartig, 2001); general improvements in mental health (Nielsen and Hansen, 2007;O'Campo et al, 2009;Bratman et al, 2012;Pearson and Craig, 2014); improved sleep (Grigsby-Toussaint et al, 2015); and improved life satisfaction (García-Mainar et al, 2015). These outcomes are not mutually exclusive: different individuals may experience multiple outcomes simultaneously (Hartig et al, 2011).…”