Don Morris, MD a researcher at the University of Michigan’s Neuropsychiatric Institute conducted a study involving 62 nursing students and 17 student pilots were interviewed for 30 minutes to determine the presence of emotional instability.   The groups were followed for 12-18 months and 4-6 months respectively. 


The nursing students were experiencing some emotional stress at the time of their physical exams required for admission to the school.  The student pilots were evaluated more intensively during several incidents of emotional distress, including their qualifying physical exam, the first flight, the initial solo flight and other training events.


Results showed a common elevation of the systolic blood pressures of 10-30 percent. The heart rate was more variable.  It slowed down in 20 per cent of the participants and accelerated in 40 per cent or more. 


With both the nurses and the pilots there was no relation  between such changes in heart  rate and blood pressure and instability as determined by the interview or difficulty in adjustment as determined by the follow-up study. In fact, when several situations of emotional stress were studied in the same individual, vascular reactions of the type outlined were so common as to constitute the normal physiological response.