Sexual stimulation and Erogenous zone. Vaginal photoplethysmography VPG can measure changes in vaginal blood volume or phasic changes in vasocongestion associated with each heartbeat. Principles of Psychoanalysis. The beginnings of sexual arousal in a woman's body is usually marked by vaginal lubrication wetness; though this can occur without arousal due to infection or cervical mucus production around ovulationswelling and engorgement of the external genitalsand internal enlargement of the vagina. Erotic stimuli may originate from a source unrelated to the object of subsequent sexual interest.
When a woman becomes aroused turned onthe blood vessels in her genitals dilate.
LDI functions by measuring superficial changes in blood flow in the vulvar tissues. It can add spice to your sex life by ensuring that the foreplay process is as drawn out as possible. One twin-study has found evidence for the heritability of both factors of SIS, but research suggests that SES variability is down to environmental factors.