“…For AR displays, most researchers have simulated AR HUDs by presenting AR graphics directly within driving scene (with no physical AR display; Caird et al, 2008 ; Kim and Dey, 2009 ; Plavšic et al, 2009 ; Charissis and Papanastasiou, 2010 ; Medenica et al, 2011 ; Dijksterhuis et al, 2012 ; Olaverri-Monreal et al, 2012 ; Kim et al, 2013 , 2016 ; Saffarian et al, 2013 ; Schall et al, 2013 ; Wai-Tat et al, 2013 ; Lorenz et al, 2014 ; Politis et al, 2014 ; Sharfi and Shinar, 2014 ), while some installed in-house prototypes (Tonnis and Klinker, 2006 ; Langlois, 2013 ; Tran et al, 2013 ), aftermarket c, or head-worn displays inside driving simulators (Sawyer et al, 2014 ; Tippey et al, 2017 ). Generally speaking, from our experience, integrating graphics directly into the driving scene (via computer graphics or video) does not afford the same accommodative and/or cognitive switching (Gabbard et al, 2019 ) that a separate AR display does; an important component for research that wishes to faithfully examine the effects of AR HUDs on driver's visual attention.…”