An image formation apparatus includes development devices placed in stations and configured to sequentially start development in an order according to the arrangement order of the stations, and a power supply unit. Each development device includes a development unit, a supply unit to supply a developer to the development unit, and a regulation member to regulate an amount of the developer on the development unit. The power supply unit applies voltages to each regulation member and each supply unit such that a first development device has a greater differential voltage when the first development device is placed in a first station than when placed in a second station in which the development is started earlier than in the first station, where the differential voltage denotes a voltage obtained by subtracting the absolute value of the supply unit's voltage from the absolute value of the regulation member's voltage.