>>Dr. Norah Dunbar: This week we're looking at some videos of people lying or telling
the truth.
[the song In the Hall of the Mountain King plays]
>>Dr. Dunbar: I asked you to look at these videos earlier, and so today we're going to
learn which ones were the lies and which ones were the truth. There are three things I want
you to remember about these videos. First of all, they're actors, which means that they're
probably already good liars. Acting ability is one of the things I think helps you to
be a better liar, because you're good at improvisation and you're also good at pretending to believe
things that you don't really believe. The second thing you should remember about these
videos is that they're all sanctioned lies, which means I told these people to lie and
they are lying without really feeling guilt or consequences because of their lie. But
they're all unscripted. They didn't know what they questions were in advance, and so they're
very naturalistic. The third thing to remember about these liars is that they're really not
interrogations. They're more like conversations, and so they might not show all of the things
that a person in an interrogation would really show. So let's look at one of our videos.
[the song In the Hall of the Mountain King plays] This is Zach, and he's being asked
a series of questions about himself.
>>Interviewer: So Zach, it's really great to have you here today. I'm glad you could
join us. We're going to go ahead and just have a very casual conversation. I'm just
going to ask you an assortment of questions and just have you respond. So first off we're
going to jump right in, what's the worst job--
>>Dr. Dunbar: One thing I want you to notice is that for all the liars there's really not
very much hand movement at all. One of the things that we're learning this week is that
nonverbal cues are really muted in liars. They don't gesture very much. They don't fidget
and look nervous like you would think a liar would. In fact, they go into what we would
call "freeze mode" where they hold their hands together or they put their hands in their
pockets or they try their best not to gesture. So you can see this several times when the
camera pans out is you can see his hands are almost always in that grip. He's not gesturing
very much at all.
>>Interviewer: --you've ever had, and why did you dislike it?
>>Zach: Um, the worst job that I've ever had was working at a Pizza Hut because I had to
deliver really late at night, and I didn't get a lot of sleep. [low sounds from video]
>>Dr. Dunbar: Notice how much eye contact he makes. He's looking straight at the interviewer
almost the whole time. There's a common misperception about liars, which is that they look away
or they look up or they're trying to avoid eye contact because they feel guilt. But all
of these liars make a lot of eye contact, probably even more than when they're telling
the truth.
>>Zach: --you know, tired.
>>Interviewer: You just didn't have the hours for it?
>>Zach: I just didn't have the mindset to deliver pizzas for too long.
>>Interviewer: Mmhmm. And about what age were you?
>>Zach: I was 17.
>>Interviewer: Okay, perfect. So you were pretty young? Just a little -
>>Zach: Pretty young, one of my first jobs.
>>Interviewer: - pretty recent. Great, great, great. Okay, yeah, um, next question. What
would you do if your boss gave you credit for someone else's work?
>>Zach: If my boss gave me credit for someone else's work--
>>Interviewer: Mmhmm.
>>Zach: --I might just let it be. I mean, if I'm getting credit for someone else's work—
>>Dr. Dunbar: Again, he's not giving off very much at all. In fact, he's really trying hard
not to give anything off. He's being very still. He's not gesturing very much. He doesn't
look around all that much. You might notice, maybe we could fast-forward to the place where
he's looking around.
>>Zach: I'm not saying it's most moral thing to do, or it's moral, but um, yeah, maybe
I would, maybe I would take the credit.
>>Interviewer: Okay. Um, okay, now this is a challenging one. Um, just so listen carefully.
Please tell me everything you did today working backwards from when you arrived here to the
moment you woke up.
>>Zach: Working backwards? Uh...
>>Dr. Dunbar: Okay, you see there he looks up at the ceiling, and you might think that
that's a cue of deception because he's looking around, he's not sure, but if you watch his
video telling the truth too, he does the same thing. The reverse-order question where he
gets asked to do something temporally but in reverse order, that's a very cognitively
demanding question, and so it's difficult even when people are telling the truth. So
you're going to see signs of cognitive load, like looking up and looking around and avoiding
eye contact even when people are telling the truth if you ask them something cognitively
difficult. Again, there's not very much nonverbally going on here.
[the song In the Hall of the Mountain King plays]
>>Dr. Dunbar: Okay, this is the second person that we interviewed. Her name's Kasey, and
you can tell that she's a little bit nervous as she's doing this because she laughs a lot.
Nervous laughter can be a sign of deception, or it may just be a sign of nervousness. But
in this case we're going to compare her truth video to her lie video and you can see the
difference in how much laughter that she does.
>>Interviewer: What would you do if your boss gave you credit for someone else's work?
>>Kasey: Uhhhhhhhhhhh, I'd take it.
>>Interviewer: Okay--
>>Kasey: [laughs]
>>Interviewer: --straight shooting.
>>Dr. Dunbar: That big laugh there that she does is probably more a sign of nervousness
even though she actually is lying about what she's saying. Let's compare that to what she
looks like when she's telling the truth.
>>Interviewer: Uh, what would you do if your boss gave you credit for someone else's work?
>>Casey: I would say that it wasn't my work.
>>Interviewer: Okay, perfect. Thank you.
>>Dr. Dunbar: No big laugh, no big smiles, she's just answering the question normally.
Where you can see, as we saw moments ago, when she was lying, then she had the big laugh
because it's like she doesn't even believe her own answer, and she knows that what she
said was kind of unbelievable. So listen how she answers the "if your boss gave you credit
for someone else's work" question.
>>Interviewer: What would you do if your boss gave you credit for someone else's work?
>>Kasey: Uhhhhhhhhhhh...
>>Dr. Dunbar: That's what we call a "filled pause". Filled pause means she's thinking.
She doesn't want to make it look like she doesn't have anything to say, but she doesn't
know what she wants to say yet, and so she fills that pause with some sort of sound.
In this case it's the long "Uhh" that she makes. Deceivers tend to make more of those
filled pauses in terms of their vocalizations than people who are telling the truth. You'll
see a similar case when we look at the verbal cues where a lot of the liars are repeating
the question back. We'll talk about that more when we talk about the verbal cues. But filled
pauses are one of the nonverbal cues that can give you a sign that somebody's not telling
the truth.
[the song In the Hall of the Mountain King plays]
>>Dr. Dunbar: Okay, this is liar number three. So he's also being asked the same questions,
and he does a couple of different things that I want to point out to you that might be an
indication that he's lying. Actually this one was interesting because most of the other
videos you guys when I polled you about these videos, were about 50/50. You weren't too
sure if they were lying or telling the truth. But this one 73% of you said he was lying,
so he was easy to peg. Let's figure out why.
>>Interviewer: Good afternoon!
>>Dwayne: How you doing, man?
>>Interviewer: Dwayne, is it?
>>Dwayne: Yes.
>>Interviewer: I'm glad to have you with us. Uh, we're just going to go ahead and ask you
a quick couple of questions, and there-we're just going to jump around.
>>Dwayne: Okay.
>>Interviewer: Just answer very casual, very informal, and we're going to go ahead and
just jump right into it, okay?
>>Dwayne: All right.
>>Interviewer: What is the worst job you have ever had, and why did you dislike it?
>>Dwayne: Working at Pizza Hut because I absolutely despise pizzas--
>>Dr. Dunbar: He does that little tongue in the cheek thing, which maybe is an indication
of deception. He just said something that he despises pizza. He knows that's not true,
and it seemed kind of uncomfortable for him to say that.
>>Interviewer: Tell me everything you did today, working backwards, from this moment
right now to the moment you woke up.
>>Dwayne: Okay, I um, I walked into the building?
>>Dr. Dunbar: Okay, there's another one. He's showing a lot of signs of uncertainty. "I
walked into the building?" He's actually asking that as a question rather than just stating
a fact. So he's doing the reverse-order question that we talked about, which is a very difficult
thing to do cognitively. But you can hear the rising intonation at the end of his statement,
and also just generally higher pitch is also a sign of deception. That's difficult to pick
up on if you're just listening to someone, but when you compare it to someone telling
a truth, then you can hear the difference in the pitch. The higher pitch usually is
a sign of deception.
[the song In the Hall of the Mountain King plays]
>>Dr. Dunbar: This is our fourth deceiver. She's very tough to pin down. In fact, most
of you had a very difficult time with her. In her deception video, only 33% of you thought
that she was lying. So I think she's our toughest one and a very good liar, probably a good
actor as well. [low sounds from video] So you'll notice right there that she has her
hands in her lap. Again, the hands never move. She makes a lot of eye contact. She smiles.
She's friendly. She really doesn't do anything that would give her away.
>>Interviewer: What is the worse job you've ever had, and why did you dislike it?
>>Kimberly: Uhmm, I was an ice cream scooper--
>>Dr. Dunbar: She didn't repeat the question. She didn't really look around. She didn't
have to think too hard. [snaps fingers] She gave her answer quickly. Makes her sound confident
that she knows what she's talking about, even though she's lying.
[the song In the Hall of the Mountain King plays]
>>Dr. Dunbar: This is liar number five, Marco. Marco sits almost the entire time with his
hands on his lap, like that. He doesn't move. He doesn't gesture, just like many of the
other liars. He's also a pretty good liar. About 42% of you correctly guessed that he
was lying in the lie video.
>>Interviewer: Good afternoon, Marco. Thank you for joining us. It's a pleasure to have
you.
>>Marco: Thank you.
>>Interviewer: We're just going to go ahead and have a very casual interview. Uhm, go
ahead and answer as you will, very, uhm, informal. And we're going to go ahead and just jump
right in, yeah?
>>Marco: Yeah, all right.
>>Interviewer: All right, what is the worst job you have ever had, and why did you dislike
it?
>>Marco: God, okay. I worked as an, uh, assistant for a mechanic, friend of mine. And, uh—well,
he started working with us on a car I have. My dad found it. He worked on my Mustang with
me.
>>Dr. Dunbar: So again you can see a lot of eye contact. You can see he's looking straight
at the interviewer. He's very casual and relaxed, doesn't show a lot of signs of tension, and
so he's another one that's going to be very difficult to pick up. I think a common theme
that you'll see through these videos is that they're very difficult to detect just from
the nonverbal cues alone. In fact, the accuracy ratings that you gave show that these people
were very hard to pick out when they were lying and when they were telling the truth.
The accuracy ratings are about 50/50, and so that is pretty much what you would expect.
So try not to focus too much on the nonverbal cues. Instead, focus on more diagnostic cues,
which we'll learn about next week.