1. A method for operating a magnetic resonance apparatus comprising the steps of: obtaining a dataset as a plurality of complex number values from an image region of an examination subject disposed in an imaging volume of a magnetic resonance imaging apparatus, at least said image region being subject to motion, and entering said complex number values into respective locations in a k-space matrix; generating a motion model identifying translational motion relative to said imaging volume with a time-dependency at least for selected points in said image region while obtaining said dataset; generating said motion model with phase values of at least two of said complex number values of said k-space matrix that are point-symmetrically located in said k-space matrix relative to a symmetry point of said k-space matrix, said at least two complex number values being complex conjugates of each other in an absence of motion and having respectively different phase values dependent on said translational motion; and correcting said complex number values in said k-space matrix using said motion model.