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A Description of the Micro-_Expression Training Tool (METT) 


David Matsumoto

San Francisco State University 


Paul Ekman

University of California, San Francisco 


The Micro-_Expression Training Tool (METT) provides self-instructional training to improve your ability to recognize facial expressions of emotion. In under an hour, METT will train you to see very brief (1/25th of a second) micro-expressions of concealed emotion. This document describes what micro-expressions are, a description of the METT, and the currently available evidence documenting its psychometric reliability and validity.  


What are Micro-Expressions? 


Micro-expressions are displays of emotion that are so brief that they are barely perceptible to an untrained observer. Ekman and Friesen had discovered these when examining films of psychiatric patients who had lied during a clinical interview, and who had concealed either plans to commit suicide or hallucinations. They later defined micro-expressions as “fragments of a squelched, neutralized or masked display. Micro displays may also show the full muscular movements associated with macro affect display, but may be greatly reduced in time. We have found that such micro displays when shown in slow motion do convey emotional information to observers, and that expert clinical observers can see micro displays and read the emotional information without the benefit of slow motion projection” (Ekman & Friesen, 1969) (p. 27). 


Why are Micro-Expressions Important? 


Micro-expressions are important because they provide reliable information about a person’s emotional state, especially when the person is trying to hide their true feelings. This is called “leakage” because they betray how individuals feel even when they attempt to conceal their true feelings (Ekman & Friesen, 1969). For instance, a non-insubstantial number of people produce micro-expressions when lying (Ekman et al., 1991; Frank & Ekman, 1997). Moreover, individuals who are good at recognizing micro-expressions are also better lie detectors (Ekman, 2003; Ekman & Friesen, 1974; Ekman & O'Sullivan, 1991), and this ability exists across cultures (Frank, in preparation).  


Measuring and Training the Ability to Recognize Micro-Expressions: Psychometric Evidence 


 The very first test developed to measure the ability to recognize micro-expressions was created by Ekman and Friesen (1974), who presented very intense facial expressions tachistoscopically for 1/25 s, and showed that emotion recognition ability was correlated with accuracy in detecting deception. A similar method using different faces was used by Frank and Ekman (1997), producing similar findings.  


One of the problems with this procedure was that tachistoscopic presentations are not life-like. In real life, micro-expressions are imbedded within a face, with an _expression preceding and following it. Additionally, tachistoscopic images leave an after-image on the retina, allowing individuals to perceive the _expression longer than it was actually presented. To remedy both these limitations, Ekman and Matsumoto created a new test using expressions portrayed by Caucasians and Asians that presented very intense emotional expressions for a brief period of time (1/5 s) imbedded within a 1 s neutral _expression of the same individual. This test was called the Japanese and Caucasian Brief Affect Recognition Test (JACBART).  


Using the JACBART Matsumoto and colleagues (2000) conducted an initial five studies documenting the psychometric properties of this new test. The findings indicated substantial support for the internal and temporal reliability of the emotion recognition scores produced; sufficient item discrimination and range; convergent validity among emotions; and reliability across response alternatives. Construct validity was established by correlations between emotion recognition accuracy scores and the personality constructs Openness and Conscientiousness using multiple measures of personality; and emotion recognition accuracy scores were independent of visual acuity in judging general facial stimuli presented at high speeds. 


In a test of the predictive validity of the JACBART using behavioral measures, Matsumoto and colleagues (2004) administered it along with the In-Basket, a task typically used to assess managerial competence. Participants assume the role of a manager and are given a basket with 33 items, and instructions to go through the in-basket, making decisions on what to do about each. Independent coders rated the participant’s responses along ten dimensions. Emotion recognition accuracy scores from the JACBART were correlated with Problem Solving, Goal Setting, and total Effectiveness.  


Recently Yoo, Matsumoto, and LeRoux (2005) used the JACBART to assess the emotion recognition abilities of international students studying in the US. The students completed a battery of psychological adjustment measures along with the JACBART at the beginning and end of the school year (September and May); they also participated in a behavioral task in the laboratory during their first semester. Emotion recognition ability scores were correlated with a variety of adjustment indices (anxiety, homesickness, culture shock) concurrently at the beginning of the semester as well as at the end (anxiety, contentment). Recognition ability was also correlated with end-of-year GPA, and with ratings of their participation in the behavioral task obtained in the laboratory session.  


Finally, Frank (in preparation) used a shortened version of the JACBART in a test of the ability to detect deceit and demonstrated that emotion recognition accuracy scores were correlated with lie detection ability for both Americans and Australians.  


The Micro-Expressions Training Tool (METT) 


Most recently, Ekman developed a new version of the JACBART that is designed not only to test individual differences in emotion recognition ability, but also to train individuals on how to recognize the signs of emotion. This test is called the Micro-Expressions Training Tool (METT) (Ekman, 2003). The METT includes feedback about the correct answers, morphed faces contrasting the most difficult to discriminate emotions, and a pre- and post-test. Frank and Ekman have each separately provided this training and, in yet to be published studies, obtained a very large increase in accuracy with less than one hour of training. Thus it appears that while most people are not tuned to the recognition of micro expressions, most can learn to become sensitive to them.  


References Cited 


    Ekman, P. (2003). Darwin, deception, and facial _expression. Annals of the New York Academy  of Sciences, 1000, 205-221.

    Ekman, P., & Friesen, W. (1969). The repertoire of nonverbal behavior: Categories, origins, usage, and coding. Semiotica, 1, 49-98.

    Ekman, P., & Friesen, W. V. (1974). Nonverbal behavior and psychopathology. In R. J. Friedman & M. Katz (Eds.), The psychology of depression: Contemporary theory and research (pp. 3-31). Washington, D. C.: Winston and Sons.

    Ekman, P., & O'Sullivan, M. (1991). Who can catch a liar? American Psychologist, 46(9), 913-920.

    Ekman, P., O'Sullivan, M., Friesen, W. V., & Scherer, K. R. (1991). Invited article: Face, voice, and body in detecting deceit. Journal of Nonverbal Behavior, 15(2), 125-135.

    Frank, M. G. (in preparation). Decoding deception and emotion by americans and australians.Unpublished manuscript.

    Frank, M. G., & Ekman, P. (1997). The ability to detect deceit generalizes across different types of high-stake lies. Journal of Personality and Social Psychology, 72, 1429-1439.

    Matsumoto, D., LeRoux, J. A., Bernhard, R., & Gray, H. (2004). Personality and behavioral correlates of intercultural adjustment potential. International Journal of Intercultural Relations, 28(3-4), 281-309.

    Matsumoto, D., LeRoux, J. A., Wilson-Cohn, C., Raroque, J., Kooken, K., Ekman, P., et al. (2000). A new test to measure emotion recognition ability: Matsumoto and ekman's japanese and caucasian brief affect recognition test (jacbart). Journal of Nonverbal Behavior, 24(3), 179-209.

    Yoo, S. H., Matsumoto, D., & LeRoux, J. A. (2005). Emotion regulation, emotion recognition, and intercultural adjustment. Manuscript currently submitted for publication. 


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