“…Indeed, as Leding (2012) noted, whereas persuasion tactics are not necessary to cause memory distortions or 'false memories', they do invariably seem to make such distortions more likely to happen. Both attitudes and memories, for instance, are changed more readily by credible messengers than by non-credible messengers (Dodd & Bradshaw, 1980;French, Garry, & Mori, 2011;Hovland & Weiss, 1951;Pornpitakpan, 2004), yet these effects diminish over time as memory for the message becomes stronger than memory for its 5 source (Hovland & Weiss, 1951;Underwood & Pezdek, 1998). Both attitudes and memories are often bolstered against change when a warning is provided in advance of an attempt to influence (Gallo, Roberts, & Seamon, 1997;Landau & von Glahn, 2004;Petty & Cacioppo, 1977), but are typically less so when the warning is instead provided afterwards (Gerrie & Garry, 2011;Greene, Flynn, & Loftus, 1982;Kiesler & Kiesler, 1964).…”