 Gendler (2008a, 2008b) claims that alief, which she proposes as an innate propensity to automatically respond to a real or apparent stimulus, is what is responsible for resistance reactions, not imagination (for more on alief, see section 3.3 of the entry on  imagination).  Alief is more primitive and fundamental than cognitive or conative imagination. It is responsible for generating a resistance response to prompted imaginings due to the perceived (perhaps unconsciously perceived or registered) possibility of contagion. 