“…Ryan's and Schwartz's (1956) and Hagen's (1974) work showed that illustrations depicting a particular object carried accurate information that specified or identified an object and increased the speed of information acquisition when information depicted in pictures was accentuated or isolated, respectively. Together with recent studies, these suggest that relevant pictorial materials can be modified to accentuate certain aspects of the pictures to facilitate learning, including clarifying meanings such as the internal and external dynamics of the depicted object (Agrawala et al, 2003;Heiser & Tversky, 2002;Horton, 1994;Krull & Sharp, 2006;Kurata & Egenhofer, 2005;Najjar, 1998;Thom, 1975). At the same time, augmenting pictures with arrows can convey additional information to readers, such as causation, direction, relational information, movement, and sequence (Agrawala et al 2003;Heiser & Tversky, 2002;Lowe & Pramono, 2006;de Koning et al, 2007;Tversky, Zacks, Lee, & Heiser, 2000).…”