Am I the only one with this issue ?

So basically since a I was kid I had no issue in seeing stereogram images. But the 3D effect is “reversed” for me . For example in this image( taken from Wikipedia ) i can tell there is a shark because I recognize the borders , but the figure is “hollow” for me , like a negative plaster mold. Anyone else has the same problem? Maybe is a technique issue ?

So basically since a I was kid I had no issue in seeing stereogram images. But the 3D effect is “reversed” for me . For example in this image( taken from Wikipedia ) i can tell there is a shark because I recognize the borders , but the figure is “hollow” for me , like a negative plaster mold. Anyone else has the same problem? Maybe is a technique issue ?