Either, depending on which study you accept.

The question is the problem. The answer is not a yes/no, but a point on a scale of multiple dimensions. Most of these studies don’t answer the question asked here, but a completely different question. And also most of these studies don’t answer the same question. Heck, it’s even a good guess that none of these studies answers the question asked here, because it’s rather difficult to make a double blind test about such questions.

Yes.