AMSTERDAM — Medical professionals and art historians have concluded that Vincent van Gogh suffered from a form of psychosis, but they could not come to a consensus about the underlying cause of his mental illness.

The diagnosis came out of a meeting of experts sponsored by the Van Gogh Museum here, in connection with its current exhibition, “On the Verge of Insanity.” It included 35 international psychiatrists, other doctors and art historians weighing in on evidence about van Gogh’s medical case.

The debate was lively and sometimes “fierce,” said Louis van Tilborgh, a professor of art history at the University of Amsterdam, who conducts research into the life and work of van Gogh at the Van Gogh Museum.

“It’s difficult to make a diagnosis, so the real progress we’ve made is that specialists in the field are talking about it, and they’ve never done this before,” he said.