In many videos, both by makers and commercial companies alike, such as this one:
The claim is made that by using a gadget that makes you 'feel' where north is by vibrating on the north side of your body (multiple implementations exist), you will eventually gain a "new sense" of where north is without noticing the actual stimulus anymore.
The video does 'cite' a study from a "university in Germany", but no actual sources are provided. Does this study exist, and if so, to what extent is it applicable to this specific project? What does it actually say? Is any other research available that this actually works?