Liar, Liar, Your Stomach's on Fire Cassandra Fong Britannia Community Secondary Floor Location : S 224 L

Understanding the universe of the digestive tract - a universe of digestive enzymes, muscles, nerves, and hormones - led me to believe that the stomach is uniquely sensitive to the gastrointestinal tract, due to a relationship between the central nervous system and the enteric nervous system. From this, I've formed a hypothesis. If the gastrointestinal tract is related to mental stress, using an electrogastrogram will improve lie detection accuracy.

The experiment consisted of a hundred healthy volunteers, each going through ten tests, for a total of a thousand tests. The volunteers first relaxed on a reclined bed, before being simultaneously attached to an electrogastrogram and an electrocardiogram. After a baseline reading of half an hour, they were presented with a deck of cards, the top of which was to be compared another card, held up from a separate deck by someone else. Each time a new card was held, a set of questions were asked, ensuring the validity of the statement. To stimulate the desire for the want of lying, each subject was presented with a fifty dollar bill, promised to be theirs if they managed to successfully trick the machines.

When subjects lied, their heart rates increased, but it also did so at other times. On the other hand, lying was consistently associated with a decrease in the slow waves of the digestive tract in conjunction with a chaotic rhythm, called arrhythmia, with no definite pattern.

The electrogastrogram seems to be a method verifiable against the current gold standard of lie detection, the conventional polygraph. Although the electrogastrogram may not replace the polygraph, it may be a very effective supplement in ensuring the integrity of the truth, resulting in a far more sophisticated polygraph of inestimable value to society.