Use of cardiometry and oculography in concealed information detection
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The article presents the results of an experimental study on the use of cardiometry and oculography to detect concealed information. It has been shown that a complex assessment of the person’s emotional-cognitive state based on cardiometric and oculographic recording of reactions to specially selected stimulus material of visual and audial modality can be successfully used in concealed information detection.
Materials and methods
We used the Cardiocode single-lead cardiograph and the GP-3 eyetracker as the instrumental basis for testing the hypothesis of the study. We have selected the above devices taking into account the previous analysis of their functional features and the basic possibility to use both devices together, the availability of the devices for a wide range of researchers and practitioners. To prove the hypothesis of the study, a complete set of the relevant subtests has been developed that implied both verbal (tests No. 1-3) and visual graphic presentation of stimulus material (tests No. 4-6).
It has been established that a combination of the average Baevsky stress index (SI) values, with mostly involuntary fixation of the examinee's attention at the main colors of the Lüscher test (primarily at green and yellow) and the calm response of the respondent to the presented stimuli in the absence of forced or suppressed respiration, can be considered as evidence for the trustworthiness of the information reported. In order to increase the effectiveness of detecting concealed information, it is advisable to separate the asthenic and sthenic variants of the involuntary manifestation of the respondent's fears of a disclosure of that concealed information. The respondent’s blocking fear of disclosing information, i.e. the asthenic response variant, manifests itself in a sharp decrease in the SI values compared to the performance indicators upon presentation of neutral stimuli. The fear initiating the hectic internal activation of cognitive and affective processes, i.e. the sthenic variant of response, manifests itself in a sharp increase in the SI values compared to the performance indicators upon presentation of neutral stimuli.
Consequently, significant signs of a desire to conceal information are any considerable deviations in the Baevsky stress index values from its averages. When using eyetrackers as means of presenting visual stimuli with elements of the eight-color Lüscher test, such SI variations are usually combined with a sharp increase in the duration of fixation of the respondent’s gaze at the verbal stimulus components (usually more than 40% of the total stimulus exposure time) and at grey and brown colors for more than 10% of the total stimulus exposure time. The effective means of overcoming the respondent’s resistance to revealing his true attitude to the objects being evaluated is the alternation of verbal and visual components of stimulus presentation.
Aleksandr S. Ognev, Vladimir A. Zernov, Elvira V. Likhacheva, Lyubov P. Nikolaeva, Mikhail Y. Rudenko, Aleksey A. Tyrtyshny, Denis S. Yesenin, Polina A. Maslennikova, Nikita V. Mizin. Use of cardiometry and oculography in concealed information detection. Cardiometry; Issue 14; May 2019; p.87-95; DOI: 10.12710/cardiometry.2019.14.8795; Available from: http://www.cardiometry.net/issues/no14-may-2019/cardiometry-and-oculography