Jonathan Alpert is gonna catch even more heat for this ... after pissing off folks by asking if "Trump Derangement Syndrome" is real, he's now saying the Jan. 6 Capitol rioters suffered from "Biden Derangement Syndrome."

The renowned psychologist joined us on "TMZ Live" Thursday and we asked him about TDS ... this on the heels of a TDS column he published in the Wall Street Journal .

Jonathan says he's seen lots of patients who were so consumed with anger and worry over Trump that they couldn't relax or sleep ... including one woman who he says couldn't enjoy a family vacation to Europe because she couldn't get her mind off DT. Gallery Launch Gallery Getty

The interesting part, though ... is Jonathan says Democrats aren't the only ones dealing with this ... he says the

See Full Page