Joe Flynn & Tasha Hanley

DARWIN THE DETECTIVE: OBSERVABLE FACIAL MUSCLE CONTRACTIONS REVEAL

EMOTIONAL HIGH-STAKES LIES

ASSERTIONS MADE BY DARWIN

Emotional expressions are:

• Inherited

• Involuntary

• Emotion-based

• Adaptive

DARWIN’S INHIBITION HYPOTHESIS

• Some “emotional” facial muscles can’t be inhibited

• Attempts to hide these will fail

• Previous studies support this

• Some facial muscles are involuntary and will signal emotions

Do you remember which part of the face the study hypothesized would be more associated with involuntary movement (lies)?

• Emotional leaking is likely to happen when the lie is complex and/or associated with strong emotions that have to be concealed

• People perform at chance levels when asked to gauge if someone is lying

• People lie (on average) 2x a day

DECEPTION

BRINKE ET AL GENERAL HYPOTHESIS

STUDY

• Looked at videotaped behaviors of 52 people emotionally asking for the return of a missing relative

• Half of these (n=26) people were later determined to be guilty of murdering the missing person (based on “overwhelming evidence”)

• Looked at muscle activation associated with surprise, sadness, and happiness

• Very specific coding system (Facial Action Coding System)

Hypothesis 1 & 2: Genuinely upset people will show more activation of the (1) corrugator supercilii and of the depressor

anguli oris (2)

Hypothesis 3 &4: Deceivers will show activation of the frontalis- which pulls up the eyebrows (only the medial frontalis is relevant to sadness) and (4) produce more

voluntary smiles (zygomatic major)

RESULTS

• Genuine pleas lasted longer

• “Honest” pleas did activate the corrugator supercilii for longer than the deceivers (H1)

• H2 was not statistically significant but seemed to be supported

• H3 was supported- liars activated the frontalis more

• H4 was also supported- deceivers DO smile more

• Note: Relationship totals exceed sample size due to several cases of

DISCUSSION

Deceptive people from the study:• Activated specific facial muscles’ associated with lying

• Had more gross frontalis activation

• Smiled more frequently (thought to mask emotional leaks)

Genuine pleaders from the study:

• Often showed activation of innate grief muscles (transcultural & Darwin said these displays facilitated human communication)

• Had contractions of the corrugator supercilii for a greater proportion of their pleas (Hypothesis 1)

• The depressor anguli oris was engaged more often (Hypothesis 2)

EXAMPLE

• http://www.youtube.com/watch?v=nP5FunbZvJ8