A polygraph exam, commonly known as a lie detector test, measures physiological responses such as heart rate, breathing, and sweat gland activity to determine truthfulness.

The polygraph records physiological changes while the examinee answers a series of questions. A trained examiner analyzes the data to assess truthfulness.

While highly reliable, polygraph accuracy depends on various factors, including examiner expertise, test conditions, and the examinee’s state of mind. Industry estimates place accuracy between 90-95%.

Attempting to manipulate the test is difficult and usually detected by the examiner. Proper preparation and honesty are the best approaches.

A typical exam lasts 1.5 to 2 hours, including a pre-test interview, the examination itself, and a post-test discussion.

Yes, polygraph exams are voluntary unless required by a specific employer, legal case, or contract agreement.

Get a good night’s sleep, avoid excessive caffeine or alcohol, and follow any specific instructions provided by the examiner.

While polygraph results are generally not used as sole evidence in court, they can be considered as supporting evidence in certain cases. However, they are widely used in investigations, workplace disputes, and pre-employment screenings.

While nervousness is normal, polygraph tests are designed to measure deceptive responses, not general anxiety. The examiner accounts for natural nervousness in the analysis.

Some medications may influence physiological responses. Inform the examiner of any prescriptions or medical conditions before the test.