This depends on the base image used in the fslmaths call.
If you are using an image where the coordinate mapping to standard space is already encoded (such as any of the MNI images) then the resulting image and ROIs will naturally be associated with standard space. You can tell this by loading it into a viewer (FSLView or FSLeyes) and seeing what "space" it reports next to the coordinate box. It should be "MNI152" if it is in standard space.
All the best,
> On 17 Aug 2017, at 16:23, Corinna Bauer <[log in to unmask]> wrote:
> Hello all,
> We have created a series of spherical rois using fslmaths around xyz coordinates that were obtained in fslview based on specific mni152 coordinates.
> Just to clarify, are these spherical rois now in mni152 space?