Development
VPG was first introduced in 1967 by Palti and Berovici, who affixed a light source and photosensitive cell onto a gynecological speculum and recorded vaginal pulse waves. Sintchak and Geer improved on the device in 1975 by using a vaginal probe. The vaginal photoplethysmograph was the first practical and reliable device for the measurement of vaginal blood flow.
Read more about this topic: Vaginal Photoplethysmograph
Famous quotes containing the word development:
“The work of adult life is not easy. As in childhood, each step presents not only new tasks of development but requires a letting go of the techniques that worked before. With each passage some magic must be given up, some cherished illusion of safety and comfortably familiar sense of self must be cast off, to allow for the greater expansion of our distinctiveness.”
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