Shiftwork, helplessness and depression.

Forty-three student nurses undertaking shiftwork for the first time participated in a study which tracked their perceptions of altered neurovegetative function, perceived criticism from others, sense of purpose and control and psychosomatic complaints. It was found that this first ever episode of shiftwork produced marked changes in all of the above. These findings have implications for circadian rhythm hypotheses of depression as well as for the methodology of future studies on cognitive or psychosocial variables in depression.