Social Engineering Blogs

An Aggregator for Blogs About Social Engineering and Related Fields

Nonverbal Clues to Deception

How crucial are nonverbal clues to detecting deception?

A recent 2017 study argues that reading nonverbal behavior is a crucial component to discovering mistruth and understanding if another person is lying. In this research, Dr. Eric Novotny and a team of scholars respond to previous research that underplays the role of nonverbal clues in everyday deception detection.

Their work built on a 2002 survey which asked participants how they tend to discover a lie. This survey found that most participants discovered lies through verbal cues or hard evidence, rather than noting tone, eye contact, or other nonverbal cues.

Based on that survey, Dr. Novotny hypothesized that there was a difference between discovering and suspecting a lie and that nonverbal behavior was critical to understanding deception detection. This distinction, he argued, was well-grounded in psychological research, because initial suspicion is a key part of changing one’s perception to the point that they would check a lie in the first place.

This initial framework led to a pair of studies. The first was a close replication of the 2002 survey. However, instead of only asking participants about what clues led them to discovering lies, they asked what clues led to the original suspicion of a lie. This adjusted survey was contrasted with a control group which simply asked the same 2002 questions.

Unsurprisingly, those asked the original questions reported non-behavioral factors, such as confessions or hard evidence as leading to their discovery, just as the previous research found. However, participants confirmed that behavioral evidence was used most frequently in terms of developing a suspicion, just as was hypothesized.

Dr. Novotny notes how extraordinarily different the results were with just a simple change in the questions asked. This raised the possibility that linguistic changes were more responsible for the differing results than anything else, so he conducted a second study to account for this.

This next survey worked with identical hypotheses but featured a variety of survey questions. The procedure was almost the same but divided the questions into four slight variants. Still, the same results were replicated despite minor differences in survey wording.

Because they also affirmed the 2002 study’s findings, Dr. Novotny and his fellow researchers concluded that discovering a lie is quite different from beginning to suspect one. This has critical implications on the field of deception detection. Instead of simply focusing on hard evidence, it is important to pick up on subtle nonverbal cues in order to begin to learn when we are lied to.

While we all have some ability to do this, it is also something that you can improve on, like all efforts to read people. That is exactly why Humintell offers both “Evaluating Truthfulness” and “Tactical Interviewing” training packages.

The Voice of a Cheater

How effective are verbal cues in exposing our emotions and character?

Throughout this blog, we have dwelled extensively on deception detection but have also focused almost exclusively on nonverbal cues. However, a new study in the journal of Evolutionary Psychology, subtle verbal cues can reveal a wealth of detail about a stranger, even including past infidelity!

In an effort to see how revealing our voices were, Dr. Susan Hughes of Albright College procured a series of audio clips of different people simply counting from one to ten. Half of the speakers had elsewhere admitted to having cheated on a romantic partner in the past, while half had not.

Then, Dr. Hughes asked a series of participants to listen to various audio clips, asking them to extrapolate what they could from just the sound of the voices. These participants were given no outside details or context besides the mundane numerical recitation.

Amazingly, when asked to rank the speakers’ likelihood to cheat, the participants’ rankings matched closely with whether the speaker had a history of infidelity!

These results do have some precedent. Past research has found that verbal cues can reveal a great deal of accurate information, including the speaker’s sex, age, race, height, weight, and even social status. Perhaps most relevantly, previous studies found links between one’s voice and the emotional states beyond deception and past sexual activity.

However, despite the groundbreaking nature of Dr. Hughes’ research, there are still many unanswered questions. For example, she declined to offer a comprehensive explanation for how this is possible!

Dr. Hughes attempted to test whether the pitch of the voice had any effect on participant evaluations. She adjusted the pitch in many of the audio clips, so that the same voice was presented with a higher or lower pitch. This had very little effect, except that men tended to associate infidelity with low pitches in female voices.

This was surprising, as previous research found that pitch does impact listener judgments. Still, while pitch has some role, it “does not represent the entire picture,” as the authors wrote. Instead, “other vocal cues such as clarity of articulation may have also contributed to perceptions of infidelity.”

Perhaps this study asks more questions than it answers, but it brings the verbal aspect of deception detection into a new light.

While we wait for more information, it might be helpful to work on strengthening your ability to detect lies face to face. Similarly, you can read some previous blogs about using microexpressions to tell when you are being lied to here and here!

Adaptation to Deception

It seems intuitive that lying gets easier the more we do it, but that may actually be supported at the neurological level!

New research found that, when we lie frequently, our brain begins to adapt to the practice of deception, to the point that we no longer feel the emotional stress that normally comes with lying. These results are important both for informing on how we practice deception but also for shedding light on the ways in which our brains adapt to patterns of, perhaps immoral, behavior.

Typically, when we tell a lie, our brain’s amygdala produces a negative emotional state, essentially making us feel stressed or uncomfortable during the process. However, a new study in Nature Neuroscience contends that, the more people lie, the less their brain produces negative stimuli.

In this study, participants were given images of glass jars filled with pennies. They were asked to report the number of pennies but were often incentivized to exaggerate the amount. While they often told the truth, they often engaged in deception when given self-interested reasons to do so.

Over the course of repeated deceptions, the researchers tracked each participants’ amygdala’s functioning, finding that they became less intensely activated each time. This even remained the case when the magnitude of the lie increased.

This last point is especially troubling, as it suggests that minor lies can escalate into major acts of deception the more accustomed to them we become. Study author Dr. Tali Sharot emphasized this point saying, “[the amygdala] response fades as we continue to lie, and the more it falls the bigger our lies become. This may lead to a ‘slippery slope’ where small acts of dishonesty escalate into more significant lies.”

In fact, the study also found that, not only did people begin to feel better about lying the more they did it, but they also became more likely to do so.

While this experiment demonstrates how our brains react to deception, it may also reflect broader trends in our ability to adapt emotionally to other actions. The lead author, Dr. Neil Garrett, alluded to the possibility of these results being replicated during troublesome behaviors besides lying.

Dr. Garrett remarked “We only tested dishonesty in this experiment, but the same principle may also apply to escalations in other actions such as risk taking or violent behavior.”

What do the results of this study mean for efforts to detect deception? In fact, it bolsters many of the challenges with lie detection, namely that habitual liars can be incredibly good at it. Not only do they learn how to lie, but their brain actually adapts to the practice!

This is all a great reason to let Humintell train you to become a better lie detector! But in the meantime, check out some helpful tips here and here.