  The behaviour of magnetic perturbations of an initially potential
three-dimensional equilibrium magnetic null point are investigated. The basic
components which constitute a typical disturbance are taken to be rotations and
shears, in line with previous work. The spine and fan of the null point (the
field lines which asymptotically approach or recede from the null) are
subjected to such rotational and shear perturbations, using three-dimensional
magnetohydrodynamic simulations. It is found that rotations of the fan plane
and about the spine lead to current sheets which are spatially diffuse in at
least one direction, and form in the locations of the spine and fan. However,
shearing perturbations lead to 3D-localised current sheets focused at the null
point itself. In addition, rotations are associated with a growth of current
parallel to the spine, driving rotational flows and a type of rotational
reconnection. Shears, on the other hand, cause a current through the null which
is parallel to the fan plane, and are associated with stagnation-type flows and
field line reconnection across both the spine and fan. The importance of the
parallel electric field, and its meaning as a reconnection rate, are discussed.
