1985 Article* about this:

Indeed, most child-care experts today disapprove of physical punishment. Dr. John F. Knutson, a professor of psychiatry...

Child-rearing experts also disagree on whether or not physical punishment deters misbehavior. Dr. James Dobson, a psychologist ...

Dr. Kenneth Kaye, a family therapist and an associate professor of clinical psychiatry ...

Other alternatives favored by psychologists include controlling the environment by placing expensive or dangerous objects out of reach, isolating youngsters for ...

Children, said Dr. Norma Deitch Feshbach, learn best in an atmosphere of reason and support, patience and understanding. Dr. Feshbach, a clinical psychologist ...

We are being trained (liked Pavlov's dog) to think that psychologists and the occasional psychiatrist are the modern experts on child rearing.... when we should know that moms and grandmothers are.

Who are we going to believe? Mom or the New York Times? This modernism and cognitive dissonance is the norm. To think otherwise is a mental disorder.... literally ... in the pages of modern psychology texts. If you go against what their textbooks say, look out for the diagnoses of mental illness pointed in
your direction.

*Source: http://www.nytimes.com/1985/06/19/garden/parents-and-experts-split-on-spanking.html