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How We Lie?

urbrainondrugs's picture

How Do We Lie?

Tiffany Ngan



What’s in a lie? That which we might present as truth our brains would show just as false. A horrible horrible pun on Shakespeare, however it brings us to the subject: lying as a variable function of the brain.


As a class, we have said that the nervous system is a system of interacting “boxes” which receive inputs and produce outputs that dictate our behavior. We have agreed that within our nervous system, there is an I-function box. This box is the element which allows us to be aware of the inputs and outputs of our nervous system. It also allows us to influence the outputs that occur. Behavior psychoanalysts believe that lying is innate in the human species. They say it is a genetically programmed in order to receive rewards and/or to avoid punishments. (1) We have agreed that the brain equals behavior as an element in our nervous system. And while lying may be something all humans are innately capable of doing, lying is not an automatic function, such as the beating of the heart. Lying is a type of conscious decision that can tell us important information about the I-function box in our nervous system. Therefore we can assume that when we lie, there is some type of biological change in the brain or internal communications of our proclaimed system of “boxes”. How then, can we track this type of change or activity in the brain?


An fMRI (Functional Magnetic Resonance Imaging) is a technique that enables researchers to create maps of the brain's networks in action as thoughts, sensations, memories, and motor commands are processed. This "brain mapping" is achieved by setting up an advanced MRI scanner in a special way so that the increased blood flow to the activated areas of the brain show up on Functional MRI scans. In 1890, Charles Sherrington and his partner Roy discovered that neural activity was closely linked to changes in blood oxygenation and blood flow in the brain. Active nerve cells consume oxygen that is being carried by hemoglobin in red blood cells. These blood cells flow in from local capillaries which in turn, causes a local increase in blood flow to regions of the brain with greater neural activity. This also causes changes in the concentrations of oxyhemoglobin and deoxyhemoglobin (2). Using fMRI the magnetic resonance (MR), or signal, of blood can be recorded, showing us different levels of oxygenation and areas of greater blood flow. By mapping these areas of activity, researchers can analyze the cognitive differences between truth and lies.

Experiments using fMRI scans and the idea of truth vs. deception began with a man name Daniel Langleben. Dr. Langleben developed a hypothesis that said in order for a person to formulate a lie, the brain needed to first stop itself from telling the truth, and then generate the deception (3). Because functional imaging (fMRI) makes cognitive operations visible by tracking the fluctuations in blood flow to groups of neurons as they fire, he believed that we would be able to see the pathway thoughts take in order to formulate lies.

In experiments done today, individuals are laid within an fMRI scanner which creates a magnetic field and records data. When inside the scanner, subjects are asked to first run a baseline interval which maps the activity of the brain at rest; then when prompted, to begin an inner monologue about themselves (motion disrupts the scan therefore subjects cannot speak during a scan) that is truthful; when prompted again, the subjects are to begin an inner monologue that is false, fabricating events and incidents which never occurred but are plausible. During these periods of monologue or rest, the scanner takes images of the subject’s brain. First, during the resting period a high resolution (4) scan is taken to serve as a template for highlighting the later stimulus-activated brain areas. Then during the truth and lie portions of activity, low resolution scans (5) are taken, these show the active portions of the brain during stimulus (inner monologue). In a typical clear single-case experiment done by Columbia’s fMRI research center, the brain scan showed more activity during the deceptive narrative, than the truthful one. The areas of greater activity are at first, those related to language, then later, during the lying portion, the amygdala, rostral cingulate, caudate, and the thalamus become “hot” spots. (6) This type of data shows that, as Langleben hypothesized, the brain must work harder to produce a fictitious narrative. It also shows that parts of the brain that are associated with lying are also closely associated with conflict, emotion, and cognitive control.

With this type of data, we can derive some interesting facts about our brain and our I-function box. The I-function box is what allows a person to experience and re-evaluate the input and output signals throughout his nervous system. It is what allows a person to subdue or override automatic reflexes such as the patellar reflex. If Dr. Langleben’s hypothesis is correct, and the brain must first stop from “blurting-out” the truth before formulating the deception, then that means telling the truth is a reflex. However, due to our I-function, we can re-evaluate and override this reflex by creating and telling a lie. In formulating the deception, the brain becomes more active in areas that are related to conflict, and emotion. From this, I can assert that the I-function box may be located in the anterior limbic and paralimbic structures of the brain. (7) Even more precisely, it could be located near the caudate (8). A caudate nucleus is one of the input nuclei in the basal ganglia, located near the center of the brain and thought to be involved with control of voluntary movements in the brain. This location of the I-function is supported by the function of the I-function box. In class we said it is what allows a person to experience his input and outputs. Emotions are the strongest things a person “feels.” It is an element that influences other behaviors as well. Located near a caudate, and/or within the anterior and paralimbic structures, the I-function would be in the greatest proximity to the areas of the brain it is said to control. In biology there is the mantra, ‘form determines function’. In the case of the I-function, I believe it is location that determines function.

FMRI scans are still a relatively new technology. As a newly budding research, the idea of mapping cognitive truth versus deceit is only about five years old. Although the conclusions I have drawn about the I-function box location and function are only speculation, they are something that I hope will be looked into as time moves along. Lying is an innate, variable function of the brain. Those with quicker responses and greater duration under stress can seem like better liars, but our brains do not lie. With fMRI technology we can begin to understand many aspects of the human brain, such as what structures control and allow people to lie. It is the beginning of many ideas and should spark an interest for the many applications it will have in the future.

WWW Sources

1) Wells, Joseph T. “A fish story or not?”. [online] available. 2007, February 23.

2) Wikipdia Encyclopedia. “Functional Magnetic Resonance Imaging.” [online] available.

3) Dr. Langleben was doing studies on ADHD children and their seeming non ability to lie. However from his experience, ADHD children could lie, but due to their situations, simply “blurted” the truth out first.

4) See

5) See

6) Silberman, Steve. Don’t Even Think about Lying: How brain scans are reinventing the science of lie detection. Wired magazine: issue 14.01. January 2006.

7) In ongoing experiments, the anterior limbic and paralimbic structures of the brain have constantly emerged as mediators of emotion. -Robinson, Robert M.D. American Journal of Psychiatry: Maping Brain Activity Associated with Emotion. Ed. Am J Psychiatry 152:3, March 1995.

8) The caudate is clearly active during the deceit portion of the fMRI scan and quiet during the truth portion. It is believed to be a person’s inner editor. It becomes active when a person must decide whether or not to tell the truth. It manages the conflict between telling the truth and creating a lie.



Serendip Visitor / calizonaman's picture

my brain

you fucking kidding me... lye really so thats not knowing any better i get close to something thinking im a threat to family city or religion.cmon man so im gonna be brain dead or wat. dont worry dude i wont go downtown races anymor..just want to say sorry and i hope we can come to a truce..