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What are emotions? What are the universal emotions? What are microexpressions? You'll investigate all of these factors in this module during your challenge to correctly identify the underlying emotions. Are you ready to begin? Well, let's get cracking.

Planning and Carrying Out Investigations

Microexpressions Brochure

Microexpressions Brochure

What are emotions?

Emotions are what we experience in response to our day to day interactions with the world and other people. Emotions are caused by a mix of our genetic makeup, how we are raised to learn to react to certain situations, and our responses to what is going on in the world around us. Emotions are anything that we feel in regards to a specific situation. Emotions can range from happiness to sadness, joy to depression, and anger to forgiveness.

What are the universal emotions?

There are 7 emotions that are considered universal. These emotions are anger, fear, sadness, disgust, surprise, happiness, and contempt. These emotions are considered to be universal because they are felt in some shape or form by all people.

What are microexpressions?

The word micro means something that is extremely small in scale. Facial expressions are the way we move or set our faces when we are responding to something with a particular emotion. Thus, a microexpression is a brief, involuntary facial expression made by people even when they are trying not to react or show emotion. Microexpressions are involuntary for the most part, meaning they cannot be controlled by a person. Often we do not even know that they are occurring.

What is an Action Unit?

The Facial Action Coding System (FACS) categorizes facial behaviors tied to different emotions based on the facial muscles that are used. Action Units (AUs) are the series of measurements used to break down and identify each type of facial expression. Each facial muscle movement is an action unit. Each of the seven universal emotions is composed of a series of AUs.

Which AUs represent sadness?

Action units that represent sadness are: the corners of the mouth droop downwards, the inner eyebrows draw inwards and upwards, and the eyes look downward while the eyelids droop. Just imitating these actions can trigger the feeling of sadness, even if we are not sad. This is because these reactions are reminding us of times when we truly were sad.

Which AUs represent anger?

Action units that represent anger are: the eyebrows draw downwards and together towards the nose, while the eyes open wide pushing the upper eyelids against the lowered brow. A hard stare usually accompanies this state. The lips are pressed together tightly and tensed, and are not puckered but firm. Sometimes the jaw is tightly clenched and the lower jaw sometimes is thrust outwards.

Which AUs represent fear?

Action units that represent fear are: the upper eyelids are raised high and pressed towards each with a strong staring look, and there is often a visible tension showing in the lower lids. The jaw is dropped open, while the lips are stretched back towards the ears.

Which AUs represent surprise?

Surprise is the briefest of all the emotions, lasting only a few moments at most. When someone is surprised, the eyes widen. The eyebrows can also rise, but they generally go straight up and do not draw in together or downwards as seen in other emotional facial responses. The mouth can also open briefly in a moment of intense surprise. A surprised expression can often mirror some of the aspects of fear, such as the eyes widening.

Which AUs represent happiness?

Happiness is often represented by smiling. Smiling, however, is not just a single facial action. When we smile, we activate a muscle, called the zygomatic major muscle, that runs from the cheekbones down at an angle to the corner of the lips, pulling the lips upwards into a smile. It is a combination of the eye and cheek muscles that indicate happiness, not just the muscles in the cheeks. Most people cannot move the part of the eyelid muscle that indicates true happiness. So, if you look closely, you can learn to tell the difference between someone who is truly happy and someone who is faking it.
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