Answer:
Polygraphy is a technique used to detect deception, consisting of a machine that measures several physiological responses such as respiration rate, blood pressure, and heart rate. The principal uses, objectives, and technical procedures of polygraphy are:
Criminal investigation: The polygraph is used to investigate crimes and identify potential suspects. Law enforcement agencies use polygraph tests to obtain information that may lead to an arrest.
Employment screening: Employers use the polygraph to screen job applicants and identify those who may be dishonest or unreliable.
National security screening: The polygraph is used to screen individuals who work in sensitive positions such as government agencies and military organizations.
Scientific research: Polygraphy is used to study physiological responses to various stimuli and understand how these responses relate to deception.
The objectives of polygraphy are to detect deception and obtain truthful information. The technical procedures involved in polygraphy include the following steps:
Pre-test interview: The examiner conducts a pre-test interview to explain the polygraph procedure and discuss the questions that will be asked during the test.
Data collection: During the test, the polygraph records several physiological responses such as respiration rate, blood pressure, and heart rate.
Data analysis: The data collected during the test is analyzed by the examiner to determine whether the subject is telling the truth or lying.
Interpretation of results: The examiner interprets the results of the test and provides a report to the requesting agency or employer.
Post-test interview: The examiner conducts a post-test interview to discuss the results of the test and provide feedback to the subject.
In summary, the principal uses of polygraphy are criminal investigation, employment screening, national security screening, and scientific research. The objective of polygraphy is to detect deception and obtain truthful information. The technical procedures involved in polygraphy include pre-test interviews, data collection, data analysis, interpretation of results, and post-test interviews.