The penile plethysmograph (PPG) is a controversial type of plethysmograph that measures changes in blood flow in the penis in response to audio and/or visual stimuli. It is typically used to determine the level of sexual arousal as the subject is exposed to sexually suggestive content, such as photos, movies or audio. A plethysmograph is an instrument for measuring changes in volume within an organ or whole body (usually resulting from fluctuations in the amount of blood or air it contains). ... Human blood smear: a - erythrocytes; b - neutrophil; c - eosinophil; d - lymphocyte. ... The penis (plural penises, penes) is an external male sexual organ. ... Stimulation is the irritating action of various agents (stimuli) on muscles, nerves, or a sensory end organ, by which activity is evoked; especially, the nervous impulse produced by various agents on nerves, or a sensory end organ, by which the part connected with the nerve is thrown into a state... This article does not cite any references or sources. ...

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, Czechoslovakia, Hong Kong,New Zealand, Norway, Spain, and the United States.

Types

There are two types of penile plethysmographs:

• 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 strain gauge and is placed around the shaft of the subject's penis to measure changes in circumference.

Tumescence is the quality or state of being tumescent or swollen. ... Typical foil strain gauge. ...

Development and uses

The original air device was developed by researcher Kurt Freund in Czechoslovakia during the 1950s. The motivation for its development was to prevent draft dodgers from claiming that they were homosexual in order to avoid military service. Kurt Freund (17 January 1914 - 23 October 1996) was a sexologist who began studies of male sexual orientation using penile plethysmography (PPG) in the early 1950s. ... Their actions were criminal offences and once they had left the country draft dodgers could not return or they would be arrested. ... Since its coinage, the word homosexuality has acquired multiple meanings. ... “Conscript” redirects here. ...

In the past, explicit or pornographic material was used as the stimuli set, but some modern systems use non-pornographic suggestive sets. This shifts the focus to the general arousal patterns rather than a specific arousal point.

The penile plethysmograph has value in screening organic versus psychogenic erectile dysfunction. Lack of sexual response during REM sleep may indicate that further evaluation by a urologist is required. Erectile dysfunction (ED) or impotence is a sexual dysfunction characterized by the inability to develop or maintain an erection of the penis. ... Rapid eye movement (REM) is the stage of sleep during which the most vivid (though not all) dreams occur. ... Urology is the field of medicine that focuses on the urinary tracts of males and females, and of the male reproductive system. ...

The device has also been used in law enforcement and in psychological experiments. One study demonstrated that experimental subjects could be conditioned to show sexual arousal (as indicated by the device) in response to images of shoes, by initially preceding pictures of nude women with images of the shoes. The experimenters inferred that the behaviourist concept of conditioning was likely to be an important influence in sexual fetishes. For the band, see The Police. ... Psychology (ancient Greek: psyche = soul and logos = word) is the study of mind, thought, and behaviour. ... Behaviorism (or behaviourism) is an approach to psychology based on the proposition that behavior is interesting and worthy of scientific research. ... Conditioning is a psychological term for what Ivan Pavlov described as the learning of conditional behavior. ... Sexual fetishism, first described as such by Sigmund Freud though the concept and certainly the activity is quite ancient, is a form of paraphilia where the object of affection is a specific inanimate object or part of a persons body. ...

United States

For many years in the United States, a scientific technique could not be used as evidence in court unless the technique was "generally accepted" as reliable in the relevant scientific community. This was known as the Frye doctrine. By 1993, after decades of use, the doctrine was rejected by United States Supreme Court in favor of a more comprehensive "reliable foundation" test in Daubert v. Merrell Dow Pharmaceuticals. In the Daubert Standard, the "generally accepted" test was no longer determinative. Several other factors could now be considered, including whether the technique had been published and peer reviewed. Some critics felt the Daubert decision lowered the standard of admissible scientific findings, while others felt that it answered some long-standing problems with Frye. To meet Wikipedias quality standards, this article or section may require cleanup. ... Federal courts Supreme Court Circuit Courts of Appeal District Courts Elections Presidential elections Midterm elections Political Parties Democratic Republican Third parties State & Local government Governors Legislatures (List) State Courts Local Government Other countries  Atlas  Politics Portal      The Supreme Court of the United States (sometimes colloquially referred to by the acronym... Holding The Federal Rules of Evidence do not require that techniques relied upon in expert testimony have general professional acceptance or have been subjected to peer review for that testimony to be judged reliable and admissible at trial. ... The Daubert Standard is a legal precedent set in 1993 by the Supreme Court of the United States regarding the admissibility of expert witnesses testimony during legal proceedings. ...

According to Barker and Howell, penile plethysmography (PPG) cannot meet most legal thresholds as a valid or relevant diagnostic tool for the following reasons:

• No standardization
• Test results are not sufficiently accurate
• Results are subject to faking and voluntary control by test subjects
• High incidence of false negatives and false positives
• Results are open to interpretation ^[1]

In State of North Carolina v. Spencer^[2], the court reviewed the literature and case law and concluded that penile plethysmography was scientifically unreliable: "Despite the sophistication of the current equipment technology, a question remains whether the information emitted is a valid and reliable means of assessing sexual preference."

The penile plethysmograph is not intended to be used as a guilt or innocence tool, but rather as a supplemental device to add to a complete psychosexual evaluation. Some of the criticisms of PPG articulated by various criminal courts relate to the blatant misuse of PPG as a tool to determine whether a defendant committed a particular crime.

In recent years, a substantial amount of research data has been gathered and reviewed, and significant steps have been taken toward standardization.

The device has also been used in many states when evaluating convicted sex offenders. The sexual assault trial of basketball player Kobe Bryant in Colorado brought this device and its use to public attention before the case was dropped in 2004, because Colorado law would have required evaluation with this device following conviction. Sex crimes are forms of human sexual behavior that are crimes. ... Sexual assault is any physical contact of a sexual nature without voluntary consent. ... Basketball is a team sport in which two teams of five active players each try to score points against one another by throwing a ball through a high hoop (the basket) under organized rules. ... Kobe Bryant (born August 23, 1978) is an American All-Star shooting guard in the National Basketball Association who plays for the Los Angeles Lakers. ... Official language(s) English Capital Denver Largest city Denver Largest metro area Denver-Aurora Metro Area Area  Ranked 8th  - Total 104,185 sq mi (269,837 km²)  - Width 280 miles (451 km)  - Length 380 miles (612 km)  - % water 0. ... Year 2004 (MMIV) was a leap year starting on Thursday of the Gregorian calendar. ...

The Ninth Circuit Court of Appeals recently addressed the procedures required before a supervised release program could include penile plethysmograph testing. ^[3]

Canada

Courts in Canada came to a similar conclusion as the United States. While the Daubert decision was greeted with harsh criticism from those who feared a flood of "junk science" in courtrooms, the Supreme Court of Canada adopted the Daubert doctrine in R. v. J. (J.L.) [2000] 2 S.C.R. 600 with very little fanfare. Interestingly, this statement by the court was contained in a decision which upheld a lower court's decision to exclude testimony by a psychiatrist who had administered several tests on the accused, including a penile plethysmograph.

After developing the device in Czechoslovakia, developer Kurt Freund fled to Canada in the wake of the Prague Spring. Freund then began using the device at the Clarke Institute in Toronto, where much of the research and published data using the device originated. People in a café watch Soviet tanks roll past The Prague Spring (Czech: Pražské jaro, Slovak: Pražská jar, Russian: пражская весна) was a period of political liberalization in Czechoslovakia starting January 5, 1968 when Alexander Dubček came to power, and running until August 20 of that year when the... The Centre for Addiction and Mental Health (CAMH) is a consortium of mental health clinics at several sites in Toronto, Ontario. ...

Use of PPG followed in the wake of the "fruit machine," a slang term for another device developed in Canada in the 1950s and 1960s as part of a Royal Canadian Mounted Police campaign involving the identification and dismissal of every gay person in the employ of the public service. The fruit machine is a jocular term for a device developed in Canada that was supposed to be able to identify homosexuals. ... The Royal Canadian Mounted Police (RCMP), also known as the Mounties or Gendarmerie Royale du Canada (GRC) in French, is both the federal and national police force of Canada. ... GAY can mean: Gay, a term referring to homosexual men or women The IATA code for Gaya Airport Category: ...

A roughly equivalent procedure for women, vaginal photoplethysmography, measures blood through the walls of the vagina, which researchers claim increases during sexual arousal. The Vaginal photoplethysmograph (VPG) is a controversial type of plethysmograph. ... The vagina, (from Latin, literally sheath or scabbard ) is the tubular tract leading from the uterus to the exterior of the body in female placental mammals and marsupials, or to the cloaca in female birds, monotremes, and some reptiles. ...

References

External links

• Skeptic's Dictionary on penile plethysmography
• Evidence of Penile Plethysmography, Psychological Profiles, Inventories and Other "Not a Pedophile" Character and Opinion Evidence Offered on Behalf of a Defendant in a Child Sexual Abuse Case is Inadmissible Under Daubert v. Merrell Dow Pharmaceutical
• "Can we identify the sexual predator by use of penile plethysmography?"
• The Penile Plethysmograph in False Allegation Cases
• Plethysmograph: A disputed device