At one time, persons with Borderline Personality Disorder (BPD) were considered untreatable. Then, in the 1960s, Dr. James Masterson developed a method that was generally successful with adolescents in an inpatient setting.
As behavioral psychology gained influence, behaviors became diagnostic criteria for mental disorders. Masterson was an outspoken critic of behavior-based diagnosis of personality disorder.
An almost limitless range of behaviors can be used in an attempt to regulate emotion or to cover up unwanted feelings. Research by Benjamin Johnson and Kenneth Levy at Pennsylvania State University finds the behavior of many persons with Borderline Personality Disorder does not line up well with the behaviors listed in the DSM.
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