There are objective tests and lots of science now, including brain scans and measuring hypocampal size etc.
All there is to know about medicine didn’t stop yesterday. Like those in the Dark Ages who though twins were result of the mother sleeping with two different men, or bleeding someone with fever let out the bad ‘humors’.....it’s always evolving.
Sorry. There is no scan, blood test that is unique.
Dr. Joseph Glenmullen, a clinical instructor in psychiatry at Harvard Medical School, “There are no medical tests to diagnose bipolar disorder, depression, or any other psychiatric condition: no blood tests, X-rays, brain scans, or any other objective tests. Medical tests should be used to rule out other conditions that can look like depression such as thyroid conditions. But all psychiatric diagnoses are subjective.”
This is one such test (study) but it would be quite challenging, not to mention prohibitively expensive to use this for screening and very difficult for a pinpoint analysis.
Currently, subjective screening and experimental dosing does work wonders for some people with the obvious symptoms.
Forgot the link: