Facial Action Coding System FAQs

The Facial Action Coding System (FACS) is an incredibly useful tool when it comes to dealing with the face.  Despite its utility, FACS is widely misunderstood.   This post answers some of the common questions about FACS.

What is the Facial Action Coding System (FACS)?

Social Engineering: Facial Action Coding System DefinitionThe Facial Action Coding System is a scientific system designed to measure facial behaviors.  Facial behaviors include individual facial movements such as pulling the eyebrows up, as well as more general facial activities like turns and tilts of the head. 1

How is FACS Used?

FACS can be used for several different things such as:

  • Describing expressions of emotion
  • Identifying between suicidal and non-suicidal patients 2
  • Predicting the onset and remission of depression 3
  • For computer generated animations 4

What is the Relationship Between FACS and Facial Expressions?

To understand how FACS and facial expressions relate, you need to know what facial expressions really are.  Facial expressions are the way the face changes as a result of one or more facial movements (or more accurately, facial behaviors.) 5

FACS on the other hand is a system for measuring and describing one or more facial movements.  Since a facial expression is composed of facial movements, FACS is a way to accurately describe the movements in a facial expression.

What is the Relationship Between FACS and Emotions?

This is one area where there is a lot of misinformation floating around the internet.  To understand how FACS and emotions relate, you first need to understand how emotions relate to facial expressions.

There are seven emotional categories that have been scientifically proven to be universally recognizable. 6  These universally recognizable emotion categories (called the basic emotions) are associated with specific sets of facial expressions. 7

For example expressions of surprise are associated with the following movements:

  • The entire eyebrow is pulled up
  • The upper eyelids are pulled up
  • The mouth is opened

Since the basic emotions are associated with specific facial expressions, FACS can be used to accurately describe these expressions of emotion.

A very common misconception is that FACS is related to reading emotions.  The problem with this is that FACS is just a measurement system, and does not interpret the meaning of the movements.  It’s sort of like saying the purpose of driving a car is to go to the grocery store.  You can use a car to go to the grocery store, but driving in and of itself can be used for several different things (e.g. driving to the movies, going across country, etc.)

Some sources incorrectly assume that FACS includes emotional interpretation.  I suspect this is because they are confusing the FACS manual with the FACS Investigator’s Guide.

The FACS manual is what a FACS coder uses to learn FACS, and as a reference for coding.  The FACS Investigator’s guide contains information such as reliability studies, how FACS compares to other measurement systems, etc.  The FACS Investigator’s guide does briefly mention possible emotional interpretations for specific FACS codings, with this caveat in the preface:

It would be ideal if the person coding facial actions did not think about the possible meaning of the behavior he scores, but focused only on describing appearance. Information about th e meaning of facial behavior has been kept out of the Manual and is mentioned only in this Guide. 8

What is the Relationship Between FACS and Microexpressions?

Another common misconception about FACS is in regards to microexpressions.  A microexpression is a brief (no more than 0.5 seconds) display of one of the seven basic emotions.  So a microexpression is really nothing more than a facial expression of emotion.  Granted it is very brief, but it’s still just a facial expression.

So to the relationship between FACS and microexpressions is the same for FACS and facial expressions: FACS can be used to describe the facial expressions that constitute a microexpression, but FACS in and of itself isn’t about microexpressions

Should I Learn FACS?

The question as to whether or not you should learn FACS is really about what you want to do, and the amount of effort Social Engineering: Learn the Facial Action Coding Systemyou are willing to invest.

If you just want to get better at recognizing emotions, then FACS is probably overkill.  Instead you should consider taking microexpression training.  However if you need to be able to discern fine facial movements, then FACS is the best option.

Another thing to consider is how much time you are willing to invest.  The average person will spend at least 100 hours studying the FACS manual, and then about 12 hours to take the FACS certification.  To compare, microexpression training usually takes about an hour.

So if you want to be better at recognizing emotions, stick with microexpression training.  If however you want to be an expert on the face, then becoming a FACS certified coder is what you need to do.

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  1. http://www.face-and-emotion.com/dataface/facs/new_version.jsp
  2. http://www.facscodinggroup.com/about/facs
  3. http://www.facscodinggroup.com/about/facs
  4. FACSGen 2.0
  5. What Are Facial Expressions?
  6. Three Mistakes People Make about the 7 Basic Emotions
  7. People sometimes mistake universally recognized to mean universally experienced.  While the basic emotions are universally experienced, they are not the only ones.  Rather basic emotions are the only universally experienced emotions that are also associated with universally recognized facial expressions.
  8. The FACS Investigator’s Guide