Visual imagery is not always like visual perception
Behavioral and Brain Sciences
The "Perky effect" is the interference of visual imagery with vision. Studies of this effect show that visual imagery has more than symbolic properties, but these properties differ both spatially (including "pictorially") and temporally from those of vision. We therefore reject both the literal picture-in-the-head view and the entirely symbolic view.
Arterberry, Martha E.; Craver-Lemley, Catherine; and Reeves, Adam, "Visual imagery is not always like visual perception" (2002). Faculty Publications. 1476.