Why do emotions exist?

Emotion is the exchange rate of a sensation or a movement. Thus there is a sensory emotion and a motor emotion.

Components of emotions:

Emotion has two components

1. Facial expression of emotion

2. Feeling of emotion

Facial expression of emotions is due to isometric contraction (shortening) of muscles of facial expression around the mouth.

Feeling of emotions is due to isotonic contraction (increase or decrease) in the hardness) of the muscles of facial expression.

There is simultaneous change in tone of Unified Skeletal Muscle (USM) and therefore we feel an emotion in the entire body.

Unified Skeletal Muscle is a physiological state of the skeletal muscular system in which all the skeletal muscles of the body isometrically contract or relax as though they were a single skeletal muscle. At rest the tone of the USM is 50%.

Purpose of emotions:

There are various sensations in the body like heat,light, pressure, taste, etc. The movements are infinite. How is it possible to compare them? How to compare a song with the taste of coffee? This comparison of the incomparable is made possible by emotions.

Whenever there is a sensation or movement the tone of the USM changes indicating the exchange value of the sensation or movement. By comparing the change in tone induced by every sensation and movement we can compare them.

Positive and Negative emotions:

Since at rest the tone of the USM is 50% a sensation can increase it or decrease it. Positive emotion increases the tone of the USM and Negative emotions decrease it.

Sensory emotions:

Sensory emotion is the change in tone of the USM induced by sensations.

There are two basic sensory emotions. They are,

1. Pleasure - Positive sensory emotion

2. Displeasure - Negative sensory emotion

Motor emotions:

Motor emotion is the change in tone of the USM induced by movements.

There are two basic motor emotions. They are,

1. Anger - Positive motor emotion

2. Fear - Negative motor emotion

Skeletal muscles associated with emotions:

Extending from each angle of mouth are four muscles. They are,

1. Zygomaticus Major - extends upwards and outwards from the angles of mouth - associated with pleasure

2. Depressor Anguli Oris - extends downwards from the angle of mouth - associated with displeasure

3. Buccinator - extends backwards from the angles of mouth - associated with anger

4. Orbicularis Oris - along with the opposite muscle encircles the mouth - associated with fear

Thus sensory emotions are due to a vertical pair of m

uscles and motor emotions due to a horizontal pair of muscles both intersecting at each angle of mouth

It should be noted that,

1. Isometric contraction of Zygomaticus Major or Buccinator increases the tone of the USM

2. Isometric contraction of Depressor Anguli Oris or Orbicularis Oris reduces the tone of the USM

Since emotions are skeletal muscle contractions they can be controlled directly though they can become involuntary and thus uncontrollable.