Polygraph based technique

Polygraph based technique

Polygraph based technique has for long been established as the method used in lie detection. It involves measuring and assessing the changes in the sympathetic nervous system, such as skin conductance response and heart rates when administering the polygraph test. The procedure is believed to heighten psychophysiological activation due to the trigger of fear of being exposed and punished. The technique, however, comes with limitations such as the ability of the results to be manipulated since people can control their physiological reaction. Intake of drugs, caffeine, and sedatives have also been linked with effect on the arousal level detected through the skin conductance hence affected the final result of the polygraph test (Zimmermann, Wittmann, Sparrer, Mühlberger, and Shiban, 2017). Inclusively, the biasness resulting from the inability of the people carrying out the test to assess the subject has also limited the polygraph method.

New technologies have been developed that help to detect lies without depending on the peripheral nervous system and overcoming the associated limitations. The study aims at improving the lie detection technique through the use of classical conditioning procedure that has startle response as the outcome variable (Zimmermann et al., 2017). The purpose of the research was, therefore, to investigate the generalization of covert lies as a primary outcome variable in determining the truthfulness of a statement. The researchers hypothesized that under fear conditioning, the participants would show a strong reaction to the known lies than to the known truth and increased response to the unknown lies compared to unknown facts resulting from generalization effects.

Study Methodology

The researchers consisted of 36 healthy participants recruited through advertisement from the University of Regensburg. The recruitment and exclusion process considered conditions like subjects between the age of 18 to 31, currently undertaking psychopharmacological medication, and involved in psychotherapeutic or psychiatric treatment done through a questionnaire. The participant was asked to create individualized stimuli materials which involved typing five true and false sentences and then ten other statements that will be given discretionary order. Thus, it is only the participants that were aware of the true sentences and those that were false. The technical environment for the presentation of the lie detection test involves the use of a brief burst of white noise for the startle elicitation (Zimmermann et al., 2017). The environment also had a system of in house air blast to be applied on the neck of the participants. Six electrodes were applied to the subjects for the measurement of the physiological process.

Before the experiment can begin, the participants have to sign an informed consent form which shows their acceptance in the procedure. All the conditions, including the stimuli and the technical environment, were then applied to the participants. The process was divided into three phases wherein each case, the participants were to read aloud the sentences they created. The reading was on a three to one ration of known to unknown that aimed at increasing the effectiveness of the fear conditioning through adding the frequency of punishment for known lies (Zimmermann et al., 2017). The sentences were presented randomly across the participants at every trail. During phase one of the procedure, no startle stimuli and air blast were presented since the participants were still unfamiliar with the situation in the laboratory. Fear conditioning was performed through punishing of the known lies using aversive air blast at the end of every sentence. There was no punishment for true statements.

Findings and Conclusions

On the fear conditioning, the results were the same as previously hypothesized by the researchers. The findings indicated that when the subjects are called to read the known lies, their reaction was stronger as compared to known truths when exposed to the startle stimulus (Zimmermann et al., 2017). The response, however, gradually decreased over the six trial blocks for both true and false statements. There were significant main effects, but no interaction effect on when both false and true statement was presented. On generalization effects to unknown lies, the result showed substantial effects on the answers and on the trial blocks but no interaction effects.

The results indicated that using the fear conditioning and measurement of startle response as the outcome variable can help in distinguishing true and false statements where there are known and unknown truths. The generalization effects also result in a difference in false and true statement of unknown truth. The aversive stimulus under laboratory conditions resulted in a negative association of the deception with the participants (Zimmermann et al., 2017). To conclude, fear conditioning was confirmed to work in the detection of lies since the results showed a stronger startle reaction to the false statement than a true statement. In general, the startle reaction was reduced throughout the experiment, which is evident when a stimulus is presented continuously.

Personal Opinion on the Study Conducted

Due to failures evident in the application of polygraph based approach to lie detection, the classical deception detection methods are more promising and can be useful in determination of true and false statements. Unlike the polygraph test that relies on the response of the sympathetic nervous system to detect lies, this method is more profound and promising. It analyses events related to potentials that could affect the ability to detect true and false sentences. The technique also involves using the startle response, a method that can discriminate between true and false statements (Lissek et al., 2014). However, to improve the effectiveness of the study, there is need to come up with a new strategy rather than using the aversive stimuli that creates ethical concerns in obtaining compliance from suspects. The research could have been improved through motivating the participants with rewards to provide realistic true or false statements. Inclusively, the study should include a baseline measurement of startle response of unknown lies and truth to prevent the differences that occur before the conditioning. A larger sample can also provide more realistic and valid findings.

The implication of the study in the practice of counselling

The current study provides a more effective means of detecting lies among subjects and suspects. Whereas the previous methods depended on the subject anxiety, the startle response depends on negative valence. It is also less susceptible to internal body control, thus making it the perfect tool in detecting lies through control of the nervous system (Zimmermann et al., 2017). In the field of counselling psychology, the method can be used in different to detect deception among the clients. In the process of differentiating true and false statements in low or high anxious participants, it is possible to measure anxiety traits among patients that help in developing therapy. Also, the aversive stimulus used in the study can be utilized in the counselling to determine the upsetting events in the life of clients and help in prescribing the best cognitive therapy (Leménager et al., 2014).