A drive section which moves a head above an information storage medium and
a control section are provided, and each track on the information storage
medium is made up of alternating first regions for writing in and reading
out user information and second regions that store information for the
positioning of the head. The control section is provided with a feedback
control value determining section for eliminating the difference between
the head position and the representative position of the first region,
which is an access object, a performing control value determining section
for determining the performing control value for the performing control
by finding the logical control value associated with the first region
where the feedback control value is determined and adding the feedback
control value to this logical control value and a performing control
section for actually controlling the drive section.