Rest and activity factors associated with  onset of cognitive decline and
neural changes 
   Lead Investigator:    Chooza Moon
   Institution      :    University of Iowa
   E-Mail           :    chooza-moon@uiowa.edu
   Proposal ID      :    1554



   Proposal Description:
   Approximately 50-70 million people in the U.S. experience disrupted sleep  (Centers for Disease Control, 2017), which may accelerate neural aging           processes. While psychological and physiological factors determine sleep         quality, age is a crucial factor in changes in sleep and wake patterns (Ohayon,  Carskadon, Guilleminault,  Vitiello, 2004). As people age, circadian rhythms     and sleep-wake cycles are more inconsistent including advancement of circadian   timing and reductions in amplitude (Neikrug  Ancoli-Israel, 2010). In             particular, sleep patterns change to shorter sleep duration, more sleep           fragmentation, longer sleep latency, and less sleep efficiency (Ohayon et al.,   2004). Circadian rhythm of rest-activity cycle is related to cognition function  and development neurocognitive disorders, such as mild cognitive impairment and  Alzheimer???s disease (AD) (Tranah et al., 2011).                                 Disruption in sleep and circadian rhythm may also contribute to amyloid           deposition and neurodegeneration, particularly reflecting decreased attention,   memory, and executive function (Blackwell et al., 2011 Killgore, 2013 Spira       et al., 2008 Sprecher et al., 2015). Prior studies provide strong foundation     in the possible links between sleep and amyloid burden (Brown et al., 2016       Ettore et al., 2019 Spira et al., 2013 Winer et al., 2019). However, results     of these studies rely heavily on subjective measures only focusing sleep         quality, lack of measures of circadian activity rhythms capturing natural sleep  and activity patterns, limited covariates in statistical models, and limited     power due to small sample sizes. Our preliminary analysis showed that disrupted  sleep and inconsistent circadian activity rhythm were associated with lower       functional connectivity in resting state networks, such as attention and         somatomotor networks in 124 cognitively normal older ad