Vulnerability and conditioning in relation to the human menstrual cycle.

An experiment aimed at testing some implications of a model of symptom acquisition is reported. In particular, the effect conditioning and extinction is examined. Sixteen female phobic patients were tested either immediately pre-menstrually or inter-menstrually. Using white noise as the UCS and a blue light as the CS, conditioned GSR responses were readily established in members of the pre-menstrual group, who also showed resistance to extinction. Subjects tested inter-menstrually were less susceptible to these effects. Those subjects taking the contraceptive pill showed increased sensitivity to the acquisition of conditioned responses.