“…Flight attendants frequently traveling across time zones exhibit cognitive deficits associated with reductions in temporal lobe structures (Cho, 2001;Cho et al, 2000). Numerous studies show that shift workers have a higher incidence of cancer (Conlon et al, 2007), diabetes (Morikawa et al, 2005), ulcers (Koda et al, 2000), hypertension and cardiovascular disease (Kivimaki et al, 2006), psychological disorders (Bildt and Michelsen, 2002), and a host of other clinical issues. These findings, although largely correlational, point to a critical role for internal circadian timing in maintaining normal brain functioning and peripheral physiology.…”