Pseudocyesis is a psychosomatic state in which a person exhibits all the symptoms of pregnancy without being pregnant. This condition is more commonly known as pseudopregnancy. Pseudocyesis has been known for centuries. Hippocrates (460-377), the ancient Greek physician, mentioned several cases of it. The Tipiṭaka mentions a young princess name Suppavāsā who had the symptoms of pregnancy for seven years and only then became pregnant and gave birth (Ud.15).
Women with pseudocyesis will stop menstruating and have abdominal swelling at a rate similar to that of real pregnancy. Their breasts become larger and more tender, the nipples swell and sometimes even secrete milk. If the condition continues long enough they may at the expected time begin to have labour pains. Pseudocyesis is caused by fear of becoming pregnant, strong empathy with someone who is pregnant or the intense desire to become pregnant. Suppavāsā's pseudocyesis was probably due to pressure from the royal family to produce an heir at a time when her husband was either impotent or temporally sterile.
If psychological states like expectation, desire or empathy can cause changes to the body as complex and dramatic as that which occur in pseudocyesis, a Buddhist would say that there is good reason to think that supposed miraculous healings and experiences are likewise due to the mind rather than to divine intervention. If one's psychological state can stop the natural cycle of menstruation then surely it can assist in the recovery from an illness. If the mind can cause the abdomen to swell in imitation to pregnancy then no doubt it make the eye see things that are not there. If simply believing that one is pregnant can make the breasts swell and secrete milk then it can just as easily conjure up the feeling of God's presence. Positing a psychological cause for unusual experiences is more rational and evidence-based than believing in a divine one. This is what we mean when we say that what God is to some religions, the mind is to Buddhism.