As already said in previous articles, a person having a neuro-sensory and perceptive system more developed than most people is said to be a highly sensitive person. Specifically, the frontal area and the amygdala, among other parts of the brain that I will mention later, are in a state of greater alert than in other people with less sensitivity.

Due to the fact that HSPs have a greater attention span and greater awareness of what surrounds them, they are able to process the information more deeply and also doing so with a large amount of detail. This specific pillar of the trait is called “sensory processing sensitivity (SPS),” and it makes the response to the environment around them (physical, social, emotional, etc.) one of “stop and observe” and then respond.

Moisés Betancort (PhD) mentions in his article “the Highly Sensitive Brain” that the SPS has been studied at genetic level and the findings of such researches is that there is a relation between the sensitivity level and gene 5HTTLPR, the one involved in the transport of a neurotransmitter called serotonin. If you have this gene variant, you have lower serotonin levels, which was originally associated with a predisposition to depression. “In fact, it doesn’t cause any mood disorder at all on its own, but it does make you sensitive to your surroundings — and more likely to learn lessons from them.” (Andre Sólo – Highly Sensitive Refuge)

Although this first gene matters, there is evidence that the biggest effect on sensitivity is related to dopamine receptors. As Andre Sólo explains it to us, “researchers have also found a connection between sensitivity and a set of 10 different gene variants related to dopamine. Dopamine is the brain’s reward chemical.” It makes sense to think that if HSPs prefer familiar environments with low saturation to stimulate them, “a sensitive system would need to feel less “rewarded” by external stimuli — otherwise, you’d be constantly drawn to the same loud, busy environments that exhaust you”, very clearly stated by Andre.

There is another neurotransmitter associated to the high emotional intensity with which HSPs live life experiences. I found an article from Ezcare clinic that explains it very concisely: “norepinephrine is a neurotransmitter that helps the body respond to stress. There is one variant that is frequently found in HSPs. If you have it, you will have significantly greater activity in the areas of your brain that form internal emotional responses to your experiences, as well as a more vivid perception of the word’s emotional components.”

Based more on a psychological aspect, I would say that this connection to your feelings makes it possible to have a lens through which you can perceive life with that “emotional vividness”, term used by Andre Sólo to explain this excess of emotionality. As this author states, HSPs “often notice emotional undercurrents where others pick up nothing” and you may “actually have a brighter palette of emotional colors” to live life to the fullest.

By way of showing some conclusions from MRI studies done to detect how the highly sensitive brain reacted to several external and internal stimuli, Dr. Betancourt conveys in his article that areas related to consciousness showed high activation: sensory information integration, empathy, and emotional response regions. Similarly, greater activation was found in the following areas: premotor cortex related to the “wait and see” strategy, in the midbrain (a dopamine-rich area activated in reward processes); in the medial temporal gyrus (related to sensing the mood of others); in the insula (a highly active area in relation to emotions, their detection and interpretation); in the areas of the inferior frontal gyrus (proposed as an important center in the mirror neuron system).

All this said in terms of genetics, the other aspect to take into account when approaching highly sensitivity is the study of the environment and how it influences genetic expression. HSPs will reap the benefits of an emotionally attuned childhood environment but will feel the negative repercussions of an emotionally unsupportive childhood environment.

Those with a genetic predisposition but better childhood experiences will have the opportunity to live fully their sensitivity while developing strong personal tools to enjoy and share to the world the uniqueness of this trait. On the other hand, those with the same genetic predisposition and oppressive, traumatic or flawed- parenting childhood are more likely to fall into the double-jeopardy model of not only sensitivity but also anxiety and depression.

As André Sólo puts it in his article, “if you combine this gene with an unhealthy childhood environment, research finds, you have a higher risk of depression and other disorders throughout life. But combine it with a safe, supportive environment, and you get better-than-normal outcomes as an adult. Basically, it may boost the effects of both good and bad upbringings.”