Nonverbal Betrayal of Feelings Albert Mehrabain Presented by Payton Ong April 25, 2005

Hypothesis Some behaviors are unwittingly emitted when a person is deliberately deceptive Exhibits positive head nodding less frequently Smiles more Speaks at a slower rate and speaks fewer words with more frequent errors

Experiment I Subjects communicate both truthfully and deceitfully Each subject gives a presentation on both advocating and condemning abortion. Additional money incentive for success and pain punishment for failure.

Results of Experiment I Each dependent measure analyzed using 2X2X14X2 factorial design. Males have more pleasant face while deceitful. Females have a higher sitting rocking movement race while given a reward for truth. Longer speech duration if given reward for truth.

Table of Results I

Experiment II Deceitful versus truthful quality of verbal communication Given specific and abstract issues, subjects try to:  Tell the truth so that the listener believes the subject is telling the truth  Tell the truth such that the listener believes the subject is telling a lie  Lie such that the listener believes the subject is telling the truth  Lie such that the listener believes the subject is telling a lie.

Results of Experiment II Analyzed using a 2X2X12X2X2 factorial design. Males less immediate if introverted. Face is more pleasant if acting to lie while actually lying Males gesture more if introverted while telling the truth. Females gesture more if extroverted and telling the truth. More head nodding if acting to lie while actually telling the truth.

Table of Results II

Experiment III Maximize a subject ’ s desire to lie without being caught. Given an ESP test with an, unknown to the subject, experimenter  Experimenter either tries or does not try to cheat. But test always ends with ESP true result. Subject is questioned about ESP result.

Results of Experiment III Analyzed using a 2X2X8 factorial design. Subjects more relaxed if extroverted. Speech rate is quicker if deceitful. Speech volume is higher if subject has low anxiety (introverted). Higher percentage of talking during conversation if truthful.

Table of Results III

Conclusion Eye Contact Facial expressions Speech duration Body movements Head nodding