A first content is selected by a user as a processing object. A change of at least a part of the first content is detected based on a time information from a timer. After the change is detected, a second content as a next processing object, a third content related to the first content, and a fourth content related to the second content, are acquired from a content information database. The second content, the third content and the fourth content, are symbolically laid out in a virtual space. The virtual space is visually presented to the user via a display.