Areas of the brain involved in origin of emotion 
-By Timothy Lyons
The analytical review from (Alvandi, 2016) discusses the formation of emotions as being a combination of sensory input and an understanding that occurs in certain areas of the brain. The identified areas of the brain involved in origin of emotion are thought to be parts of the limbic system, brainstem, cerebral cortex, amygdala and forebrain areas. The caution from this paper is that it is difficult to know all of the regions of the brain that deal with emotions since there are no specific neurons or synaptic connections that have yet been identified.
Further discussion comes from (Carson & Birkett, 2017) and identifies the amygdala as providing a great deal of the processing of emotions. There are links to hormonal responses that respond to external stimuli that control emotions. The specific areas of the amygdala that play a prominent role in emotions are the lateral nucleus, the basal nucleus, and the central nucleus. These are linked to learning of emotions but also processing the emotions to provide hormonal and behavioral changes as well as the use of autonomic functions in relation to emotions.
Another factor for emotional origin can be learning according to (Carson & Birkett, 2017). There have been studies that have shown that fear of dogs can take place in children even when they have not been attacked. In these cases, the children can merely watch others being attacked to gain the emotion of fear in this case. With this learning, the other factors of hormones, behavior changes and autonomic functions are discussed in relation to emotions. The hormones serve to reinforce the emotional reactions. The changes in behavior seem to be what assists in preparing the external reaction of the brain after the autonomic nervous system assists the body in converting stored energy into movement in cases such as when fear is the primary emotion being originated.
References for Areas of the brain involved in origin of emotion
Alvandi, E. O. (2016). A Review on Meanings of Emotions: Steps to a Neural-Informational Notion of Semantics. Cognition, Brain, Behavior, XX(1), 45-63.
Britannica.com. (n.d.). Sexual dimorphism. Retrieved January 29, 2017, from https://www.britannica.com/science/sexual-dimorphism
Carlson, N. R., & Birkett, M. A. (2017). Physiology of Behavior (12 ed.). Boston, MA: Pearson Education.
Hayes, S. C., Strosahl, K. D., & Wilson, K. G. (2012). Acceptance and Commitment Therapy (2nd ed.). New York, NY: Guilford Press.