Are you aroused — or not really?
First step in creating an accurate test on a psychological concept is an accurate definition. Currently the consensus on the definitions of desire and arousal are very malleable, but there is a common view that desire is a psychological and arousal is a physiological reaction, which is the blood flow into the genitals, to sexual stimuli. Thus presently it is important to design the tests according to these bases. Generally self-reports are used to measure desire and physical tests for arousal.
Earliest arousal test was penile plethysmography for men and vaginal plethysmography for women. By quantifying the circumference of the penis before and during the state of arousal, and by illuminating the capillary beds of the vaginal wall, both of them essentially tried to determine blood flow into the genital areas. Mainly there are two questions that can be raised: is blood flow the physical indication of sexual arousal and are these devices really calculating the blood flow?
When a man is in the research room, he sits on a chair some kind of a sexual stimulus in front of him (a magazine, pictures, audio, etc.) A researcher comes into the room and puts the rubber ring over the penis and then leaves the room. He is actually watching the man through a mirror-window and the man is aware of this situation. When a woman is in the research room, similarly, a tampon like device is inserted into her vagina, and then she is exposed to sexual stimuli.
What about the effects of the ring and the tampon-like device? Do they generate arousal? Can those devices turn subjects on? Does it matter if they do or not? Is the researcher affecting the arousal levels by being in the next room observing? What about the arousal levels of paraphilic individuals? Or of anxious individuals? More importantly is there a baseline for the blood flow? Is there a zero point?
Plethysmographies are currently not in use because of the unsatisfactory answers to the questions like the ones above, they have been replaced with other tests. I’ll talk about them in my next blog entry.