Is There a Difference Between Computation and Representation?

When I started Trying to figure out what physical computation was I thought oh that's the digital kind of Process you know computations digital that was a wide-fert assumption at the time and the brain is not digital. Then it occurred to me eventually thanks to various inputs including by Mars and no Koski who's a Polish philosopher that There's a broader notion of computation than digital computation That includes other things like analog computation and other sorts of computation so then I flipped and I realized that once you have the more general notion there are arguments that the brain is computational but then I also realized that there's also an argument that neural computation  is different in kind both from digital computation and from analog