Fourier transformation has become known in the field of medical imaging following the introduction of MR imaging; currently it is still probably one of the most difficult areas of MR image formation to conceive. However, Fourier transformation and K-space concept is indispensable for the understanding of most artefacts as well as the operation of fast/ultrafast MR pulse sequences. The lines of K-space represent different spatial frequency information applying to the whole image, as well as defining the photographic contrast
and recorded detail. All digital images can be constructed using spatial frequency elements, furthermore the images may be analyzed with
Fourier transformation. Lately, according to the signal channel model accepted in human visual perception research, visual information in the human brain may also be constructed using spatial frequency schemes.