It perhaps may only be equilavent to "zoning out" in the short term, and may not actually seem like a bad thing. But over a longer period of time, it gives a more numb feeling, added with a sense that it's not going to go away anytime soon. This is combined with the body and the mind not coordinating so actively together, which seems to lead to moments where sensations which should have been felt over a period of time are felt all at once - maybe akin to getting pins and needles.