Types
There are two types of penile plethysmograph:
- Volumetric air chamber
- When this is placed over the subject's penis, as tumescence increases, the air displaced is measured.
- Circumferential transducer
- This uses a mercury-in-rubber or indium/gallium-in-rubber ring or electromechanical strain gauge and is placed around the shaft of the subject's penis to measure changes in circumference.
The circumferential type is more common, but the volumetric method is believed to be more accurate at low arousal levels.
Significant suppliers of PPG machines include Behavioral Technology Inc. and Medical Monitoring Systems. The device is known to be used in Brazil, Britain, Canada, China, Czech Republic, Hong Kong, New Zealand, Norway, Slovak Republic, Spain, and the United States.
The surgical machine is supplied as CaverMap by Blue Torch Medical Technology, Inc.
A roughly equivalent procedure for women, vaginal photoplethysmography, measures blood through the walls of the vagina, which researchers claim increases during sexual arousal.
Read more about this topic: Penile Plethysmograph
Famous quotes containing the word types:
“If there is nothing new on the earth, still the traveler always has a resource in the skies. They are constantly turning a new page to view. The wind sets the types on this blue ground, and the inquiring may always read a new truth there.”
—Henry David Thoreau (1817–1862)
“The wider the range of possibilities we offer children, the more intense will be their motivations and the richer their experiences. We must widen the range of topics and goals, the types of situations we offer and their degree of structure, the kinds and combinations of resources and materials, and the possible interactions with things, peers, and adults.”
—Loris Malaguzzi (1920–1994)
“He types his laboured column—weary drudge!
Senile fudge and solemn:
Spare, editor, to condemn
These dry leaves of his autumn.”
—Robertson Davies (b. 1913)