How can the aversion response be explained neurologically? If Dopamine and Dopamine D2 receptor is involved in craving, wanting and clinging towards something or incentive salience


  Dopamine is closely associated with reward-seeking behaviors, such as
  approach, consumption, and addiction.[38] Recent researches suggest
  that the firing of dopaminergic neurons is a motivational substance as
  a consequence of reward-anticipation. This hypothesis is based on the
  evidence that, when a reward is greater than expected, the firing of
  certain dopaminergic neurons increases, which consequently increases
  desire or motivation towards the reward (from dopamine on Wikipedia )


What is the opposite mechanism in humans - by which we are experiencing aversion from something?

For example, someone finds something rotten, stinky and covered in white fuzzy mold in a plastic bag. Eww! Gross! Get it away! don't touch it! Keep distance. What is neurologically responsible for the person's feeling of aversion towards an object like that?

Are there different pathways to aversion?

For example, would seeing a person who looks like a witch from fairy tales (old, ugly, rotten teeth, lots of warts, body odor) cause the same aversion response as moldy food?
I remembered that Disgust is one of the 6 major emotions and there is quite a lot written about it:


  The neural basis of disgust
  
  The scientific attempts to map specific emotions onto underlying
  neural substrates dates back to the first half of the 20th century.
  However, it was not until the mid-1990s when it was recognized that
  six basic emotions, including disgust, were each related to a specific
  neural structure and therefore considered to be a part of the clinical
  neurosciences.[23] Functional MRI experiments have revealed that the
  anterior insula in the brain is particularly active when experiencing
  disgust, when being exposed to offensive tastes, and when viewing
  facial expressions of disgust.[24] The research has supported that
  there are independent neural systems in the brain, each handling a
  specific basic emotion.[4] Specifically, f-MRI studies have provided
  evidence for the activation of the insula in disgust recognition, as
  well as visceral changes in disgust reactions such as the feeling of
  nausea.[4] The importance of disgust recognition and the visceral
  reaction of "feeling disgusted" is evident when considering the
  survival of organisms, and the evolutionary benefit of avoiding
  contamination.[4] [edit]