The art of deception has been central to research in the fields of psychology and neurophysiology. Zuckerman and colleagues (1981) found that producing a lie takes more cognitive effort than telling the truth. Due to this cognitive stress, many telltale physical signs of lying arise, including pupil dilation, fewer accompanying hand motions, response latency and speech hesitation along with increased neural activation in areas important

to executive functioning like the frontal lobe. It has also been found that increases in cognitive effort decreases respiratory sinus arrhythmia (RSA) (Aikins et al., 2010). Pennebaker and Chew (1985) also examined physiological responses to lying and found that skin conductance levels, respiration rate and heart rate heighten when telling a lie due to stress associated with the need to monitor and inhibit one’s own behavior when lying.

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Many studies that examine deception use the Control Question Technique (CQT), a method that involves asking people with an incentive to lie innocuous questions such as, “where are you from?” along with questions that are relevant to what they might have an interest in concealing. This method is often paired with a polygraph test that measures other physiological correlatives of lying such as increased heightened heart rate (Kleinmuntz et al., 1982). Although known as the “lie detector”, the polygraph test does not directly detect lies, but rather indirectly records involuntary physiological responses associated with lying like heart rate, respiration rate, and skin conductance. The detector, itself, uses standard physiological equipments to measure blood pressure, galvanic skin response (GSR), respiration and heart rate, and compile the data into a singular recording device.

Some substances can produce physiological effects similar to those associated with lying. Physiologically, caffeine mimics the effects of epinephrine, a sympathetic nervous system stimulant, which leads to an increased heart rate and respiration rate (Mahmud et al., 2001). Caffeine is a commonly used stimulant which acts as an antagonist to adenosine receptors via G-protein pathway to produce its stimulant effects (Fisone et al., 2003). Studies have shown that caffeine can improve aspects of cognitive performance such as secondary memory and speed of attention (Scholey et al., 2004). One study has shown that the effects of caffeine were usually maximal 30 minutes after ingestion (St. Claire et al., 2010). Caffeine administration led to an increase in mean blood pressure as well as a rise in heart rate (Robertson et al., 1978). Similarly, when a

person lies, the common signs are elevated blood pressure and increased heart rate.

Thus, this led us to the question as to whether caffeine consumption can enhance the physiological effects of lying. Based on previous studies, we hypothesized that caffeine would amplify the physiological effects of lying. In order to carry out the experiment, we performed a set of tests to measure the effects of lying and caffeine consumption on heart rate and respiration rate and volume. We predicted that heart and respiration rates, along with respiration volume, would be significantly higher when a person is lying than when telling the truth. These measurements would also be significantly higher in subjects that consumed caffeinated coffee compared to subjects who consumed decaffeinated coffee. Subjects that consumed caffeine would be expected to have a markedly higher heart rate and respiration rate and volume, indicative of an interaction between lying and caffeine consumption responsible for an enhancement in physiological response. Many studies use subjects with an inherent motivation to lie, such as criminals trying to cover up a crime, but when drawing from a population with no apparent criminal record, it is often difficult to provide participants with a seemingly natural motivation to deceive. To resolve this issue, our present study used an unorthodox but certainly proven motivator for the demographic we examined: an incentive to lie for the acquisition of candy.

Methods

The experiment we conducted to test our hypothesis was a controlled experiment. We

used a 2x2 mixed design to test the effect of our independent variables (caffeine consumption and lying) on the physiological

responses of heart rate, respiration rate and volume. Caffeine consumption was the between subjects independent variable. We randomly assigned 14 participants (7 female, 7 male) to either the caffeinated group or decaffeinated groups with approximately equal numbers of females and males in both groups. Prior to beginning each trial, subjects were asked to sign a consent form to acknowledge a possible consumption of caffeine at normal dosage and completed a questionnaire about their normal usage of caffeine (See Appendix I, II). After the subject began to consume the drink, we waited 20 to 30 minutes for the caffeine to take effect. The dosage for the coffee used for the experiment

followed the guideline from the Folgers Coffee website and was adjusted for subjects that indicated heavy caffeine consumption. Subjects that reported daily consumption of 3 or more caffeinated beverages were given twice the standard dosage of coffee in one cup. The human lie detector questioned subjects and determined whether they were lying. The data analyst compiled data in the computer and made sure tests were run correctly. The pulse reader marked down the recordings from the pulse ox in 5-second intervals. Another researcher recruited subjects and randomly

assigned them to caffeinated or decaffeinated groups, but did not tell the other researchers conducting the experiment whether each subject consumed caffeinated or decaffeinated drinks to provide a double blind experiment condition.

After waiting 30 minutes, the subjects were attached

Figure 1. Caffeine Consumption had no significant effect on heart rate (F(1,12)=4.28, p=0.137). Each bar represents mean heart rate (±SE) of all subjects within the decaffeinated and caffeinated groups (n=7, n=7, respectively).

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to the respiration monitor and pulse monitor. Subjects were instructed to sit still during the experiment to avoid false readings from the respiration monitors. They were then informed about the process of the experiment and then baseline physiological measurements were established for each test as participants made 3 truthful statements and lied once about their height. Participants were then given a handout with 10 questions, with none of the questions being too personal (Appendix III). Subjects were told that the human lie detector would ask them the questions on the handout in order, and that out of the 10 statements they would have to make 5 would have to be truthful and 5 would have to be false. The questions were asked in a consistent order, but subjects were told that they could respond with a lie to any of them as long as 5 statements were truthful and 5 were false. Subjects were also informed that the human lie detector would be observing their facial expressions to determine whether they were lying. It was made clear to the subjects that for every statement that the human lie

detector could not correctly determine as true or false, they would receive one piece of candy as an incentive to successfully lie. As subjects made each statement, they marked on their handout whether it was true or false, while the human lie detector simultaneously marked whether she thought that the subject was lying or telling the truth (Appendix IV). Two additional experimenters recorded heart rate, respiration rate and respiratory volume for

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each statement. At the end of the experiment, the subjects’ handouts and the human lie detector’s veracity decisions for each statement were compared, and subjects were given a piece of candy for each incorrect judgment made by the human lie detector.

After the physiological data was collected from all participants, it was compiled in an Excel spreadsheet and an ANOVA test was administered to assess the effects of caffeine consumption and lying on respiration rate, heart rate, and volume of respiration. A possible interaction between caffeine and lying was also explored using t-test analysis.

Results Caffeine had no significant impact on heart rate

Contrary to our hypothesis, there was no considerable effect of caffeine consumption on heart rate (p=0.137). Subjects who consumed decaffeinated coffee had a slightly higher average heart rate (89.34 ± 24.76 bpm) than subjects who consumed caffeinated coffee (79.94 ± 15.43 bpm), but the difference was not significant (Figure 1 and Table 1).

Our hypothesis that an interaction between caffeine consumption and lying would occur

and enhance heart rate was not supported (p=0.26) (Table 2). A t-test showed that subjects who consumed caffeinated coffee had the same heart rate when they made truthful statements (79.89 ± 13.70 bpm), as when they made false statements (79.99 ± 17.50 bpm) (Table 3). Subjects who consumed decaffeinated coffee also had no significant difference in heart rate when they made truthful statements (88.04 ± 23.34 bpm) as opposed to false statements (90.63 ± 26.29 bpm), (p=0.85) (Table 4). Lying had no significant impact on heart rate

The overall trend for mean heart rates showed an increase mean heart rate for the false statements group as compared to the true statements group within each subject (Figure 2). Out of the fourteen subjects, all but three subjects had higher average heart rate when they replied with a lie than when they were telling the truth. The overlap of the standard error bars demonstrated that our data was not statistically significant. The paired t-test in Table 5 confirmed the findings from the standard error bars, in that the difference between the true and false statements group for mean heart rates was not statistically significant (p= 0.4596) .

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subjects’ respiration rates during true statements and false statements. The mean respiration rate recorded during subjects’ true statement was 0.55 bps and 0.559 bps during

false statements (Figure 3). We found that there was no statistically significant difference in respiration rates when our subjects were lying or telling the truth (p=0.9816) (Figure 4 and Table 6). Caffeine’s effect on respiration rate

To assess the effect of caffeine on the rate of respiration, the average respiration rate for each statement was analyzed for both the caffeinated and decaffeinated group (Figure 5). Out of the 10 statements, all but two statements (#7, 10) had higher respiration rates for the decaffeinated group (Figure 5). A paired t-test analysis indicated a higher respiration rate in the decaffeinated group (0.611133 ± 0.123) compared to the

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In the earlier graph, each statement topic included both the true and false statements for each group. To account for possible differences in respiratory rates due to the statement being true or false, another graph was assembled to separate the values based on

whether the statement was true or false for each group (Figure 6). There were no statistically significant trends between these classified groups (P=0.352) (Table 8). Thus, caffeine alone, does not have significant effect on respiratory rate. Caffeine increased respiratory volume for only true statements

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relationship between the true and false statements for either caffeinated or decaffeinated group (P=0.467, P=0.881, respectively) (Table 10. A, B). When examining the effect of caffeine on the respiratory volume for true and false statements separately, there was considerable effect of caffeine consumption on respiratory volume for only the true statements (p=0.0348) (Table 10.C, D).

Discussion

We found no statistically significant difference in respiration rates when our subjects were lying or telling the truth. This disproves our hypothesis as it stated that respiration rates would sharply increase when caffeinated subjects lied. Ultimately, this was not observed.

We hypothesized that during an act of deception, the heart rate would increase. However, this hypothesis is inconclusive; while we have an overall trend of higher mean heart rate in the false statement group than the true statement group, there was no statistical significance in the difference. Thus, this hypothesis is uncertain.

We hypothesized that caffeine consumption would increase heart rate and respiration rate. Our finding, that subjects who consumed caffeinated coffee had a lower heart and respiration rate than subjects who consumed decaffeinated coffee, was unanticipated, but similar results have been reported in some studies involving low dosages of caffeine administration. One such study administered a low dose of caffeine to rabbits, which lowered their heart and respiration rates. After caffeine dosage increased past a critical point, heart

rate in rabbits increased rapidly (Barry et al. 2007). We administered a relatively low dose of caffeine to each subject in the caffeinated group; our results could be explained to that of similar findings by Barry and colleagues. For future experimentation, using a higher dose of caffeine would provide stronger physiological responses and may produce our hypothesized results.

While respiration rate was lower in caffeinated subjects, though not to a statistically significant degree, respiration volume was significantly higher in the caffeinated groups compared to the decaffeinated groups for true statements. An increase in respiration volume indicates that subjects who consumed caffeine took deeper breaths. Lower respiration rate is often accompanied by higher respiration volume because it normally takes longer to breathe deeply than to take short, shallow breaths at a high rate. It would be interesting to explore whether this inverse relationship between

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respiration rate and respiration volume persists at higher doses of caffeine consumption.

For each group of subjects, standard deviation was very high, (SD=24.79 in the decaffeinated group, and SD=15.43 in the caffeinated group). Within the decaffeinated group, mean heart rates ranged from 51.71 beats/min to 133.53 beats/min. These high standard deviations in such a small sample size (7 subjects per group) limited the power of our statistical tests and made it difficult to reject the null hypothesis that caffeine had no effect on heart rate.

For future studies examining the effect of caffeine on heart rate, a larger sample size would be ideal to lessen the impact of variation. A larger sample size would also help to add power to our statistical analysis. A stronger manipulation of deception could be

performed by putting more pressure on participants to lie, or by providing a stronger incentive than candy to deceive. Telling participants that lying effectively is a mark of intelligence, having a larger audience watching the participant, or offering a large amount of money for successfully lying would all serve the purpose of increasing pressure on subjects and providing a stronger incentive to lie.

While the results showed limited statistical significance, our experiment provides a basis for further research on the physiological effects of caffeine and deception. With stronger manipulations and access to a larger population size, trends found in this study might gain greater support and further illuminate the intricate physiological relationship between deception and caffeine consumption.

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References

Aikins, D., Martin D., & Morgan, A. (2010). Decreased respiratory sinus arrhythmia in individuals with deceptive intent. Psychophysiology, 47(4); pp. 633-636.

Barry, R., Clarke, A., Johnstone, S., & Rushby, J. (2007). Timing of caffeine’s impact on autonomic and central nervous system measures: Clarification of arousal effects. Biological Psychology, 77; pp. 304-316.

Fisone, G., Borgkvist, A., & Usiello, A. (2003). Caffeine as a pyschomotor stimulant: Mechanism of action. Cellular and Molecular Life Sciences, 61(7-8); pp. 857-872.

Kleinmuntz, B., & Szucko, J. (1982) On the fallibility of lie detection. Law & Society Review, 17; pp. 85-104.

Mahmud, A., & Feely, J. (2001). Acute effect of caffeine on arterial stiffness and aortic pressure waveform. Hypertension, 38; pp. 227-231.

Pennebaker, J., & Chew, C. (1985). Behavioral inhibition and electrodermal activity during deception. Journal of Personality and Social Psychology, 49; pp. 1427–1433.

Robertson, D., Frolich, J., Carr, R., Watson, J., Hollifield, J., Shand, D., & Oates, J. (1978). Effects of caffeine on plasma renin activity, catecholamines and blood pressure. The New England Journal of Medicine. 298; pp. 181-186.

Scholey, B., & Kennedy, D. (2004). Cognitive and physiological effects of an “energy drink”: An evaluation of the whole drink and of glucose, caffeine and herbal flavouring fractions. Psychophrmacology, 176; pp. 320-330.

St. Claire, L., Hayward, R., & Rogers, P. (2010). Components of stress: Caffeine makes men less, but women more effective as partners under stress. Journal of Applied Social Psychology, 40; pp. 3106-3129.

Trippenbach, T., Zinman, R., Milic-Emili, J. (1980). Caffeine effect on breathing pattern and vagal reflexes in newborn rabbits. Respiration Physiology, 40; pp. 211-225.

Zuckerman, M., DePaulo, B., & Rosenthal, R. (1981). Verbal and nonverbal communication of deception. Advances in experimental social psychology, 14; pp. 1–59.

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IMPORTANT: PLEASE RESPOND IN FULL SENTENCES.

Statement Topic List: (circle T/F during test)

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