1. A method, comprising: generating a visual field image to be visually recognized by a user within a virtual space image, the virtual space image forming a virtual space within which the user is immersed; generating a transitional image to be visually recognized by the user during a transitional period, the visual field image being updated during the transitional period; and displaying the visual field image and the transitional image using a head mounted display, wherein generating the transitional image comprises one or more of: updating the visual field image in synchronization with a movement of the head mounted display; and updating the visual field image without synchronization with the movement of the head mounted display by generating the transitional image having a reduced information amount to be visually recognized by the user.