Plethysmograph

The penile plethysmograph is an individually applied physiological test, that measures the flow of blood to and from the genital area. Over the past 20 years the plethysmograph has evolved into a sophisticated computerized instrument capable of measuring slight changes in the circumference of the penis. 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. Much research has accompanied the evolution of the seismography. Generally, the plethysmograph is recognized as the best objective measure of male sexual arousal because blood flow into the penis is the only measure of sexual arousal that doesn't seem to be influenced by other factors. The objectiveability to measure penile arousal has helped the plethysmograph evolve into one of the important tests in the assessment and treatment of male sex offenders.

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