June 13, 2008 Delaying an adolescent's school start time by one
hour has a positive effect on his or her cognitive performance,
according to a research abstract that will be presented on June
12 at SLEEP 2008, the 22nd Annual Meeting of the Associated
Professional Sleep Societies (APSS). The study, authored by Orna
Tzischinsky, PhD, of Emek Yezreel College in Israel, focused on
47 eighth graders from two classes, who were divided into
experimental and control groups for a two-week period. On week
one, the experimental class began their school day one hour
later than usual (at 8:30 a.m.), while the control class began
at the regular time (7:30 a.m.). On week two, both classes began
at 7:30 a.m. The subjects were asked to maintain their habitual
sleep-wake pattern. Actigraphs were worn to monitor sleep-wake
patterns. On the fifth day of each week, the students performed
a cognitive test. According to the results, during the first
week, the experimental class woke up 51 minutes later on average
than the control