An image receiving unit receives a current image acquired by imaging a subject. A character information acquisition unit acquires character information from past medical information relevant to the current image. A position receiving unit receives a designation of a position in the current image. A character specifying unit specifies characters relevant to the position received by the position receiving unit from the character information acquired by the character information acquisition unit. A display control unit performs control to display the character specified by the character specifying unit so as to be emphasized on a display unit.