“…Attentional impairments arise shortly after the memory deficits in AD (Parasuraman and Haxby, 1993;Parasuraman and Martin, 1994;Parasuraman et al, 1995;Perry and Hodges, 1999;Rizzo et al, 2000;Berardi et al, 2005;Bohnen et al, 2005). Similar to memory, activation of the cholinergic system improves attention in humans (Furey et al, 2006(Furey et al, , 2008Ricciardi et al, 2013) and NHPs (Callahan, 1999;O'Neill et al, 1999O'Neill et al, , 2003Schwarz et al, 1999;Terry et al, 2002;Katner et al, 2004), whereas cholinergic blockade produces attentional impairments in both species (Callahan et al, 1993;Callahan, 1999;Taffe et al, 1999;Thienel et al, 2009a,b).…”