Brain scan shows when people think you’re lying

Jury consultants, start your engines

Let’s say your client — the one with the violent past, long rap sheet, and general air of no credibilitiy whatsoever — is on trial for murder.

He tells his story: “The other dude did it!”

You believe him.

Will anyone else believe him? How should he present his story to the jury? You could use a mock jury and some brain imaging.

This is what your brain looks like when you believe someone (fmri image below):

This is what your brain looks like when you don’t believe someone (fmri image below):

This is what your brain looks like when you are uncertain (fmri image below).

This is brain imaging as sort of a lie-detector-detector (OK, a lame oblique homage to the Simpsons linguistic style, see, e.g., “bread maker maker“)

The paper is, “Functional neuroimaging of belief, disbelief, and uncertainty.” See the full abstract after the jump

Ann Neurol. 2007 Dec 10 [Epub ahead of print]

Functional neuroimaging of belief, disbelief, and uncertainty.

Harris S, Sheth SA, Cohen MS.

University of California Los Angeles Brain Mapping Center, Los Angeles, CA.

OBJECTIVE: The difference between believing and disbelieving a proposition is one of the most potent regulators of human behavior and emotion. When one accepts a statement as true, it becomes the basis for further thought and action; rejected as false, it remains a string of words. The purpose of this study was to differentiate belief, disbelief, and uncertainty at the level of the brain. METHODS: We used functional magnetic resonance imaging (fMRI) to study the brains of 14 adults while they judged written statements to be “true” (belief), “false” (disbelief), or “undecidable” (uncertainty). To characterize belief, disbelief, and uncertainty in a content-independent manner, we included statements from a wide range of categories: autobiographical, mathematical, geographical, religious, ethical, semantic, and factual. RESULTS: The states of belief, disbelief, and uncertainty differentially activated distinct regions of the prefrontal and parietal cortices, as well as the basal ganglia. INTERPRETATION: Belief and disbelief differ from uncertainty in that both provide information that can subsequently inform behavior and emotion. The mechanism underlying this difference appears to involve the anterior cingulate cortex and the caudate. Although many areas of higher cognition are likely involved in assessing the truth-value of linguistic propositions, the final acceptance of a statement as “true” or its rejection as “false” appears to rely on more primitive, hedonic processing in the medial prefrontal cortex and the anterior insula. Truth may be beauty, and beauty truth, in more than a metaphorical sense, and false propositions may actually disgust us. Ann Neurol 2007.

PMID: 18072236 [PubMed - as supplied by publisher]

Tags: Brain cells, Brain scan, deceit, frontal lobe, law, lie detector, limbic system, Neuroeconomics and neuromarketing, neuroscience, polygraph, psychology, Psychopath (also sociopath)