I led a workshop the other day on self-criticism and got the intruiging questions whether I thought that highly-sensitive persons were more likely to be self-critical than others. I forced me to once more dive into the scientific evidence around highly sensitive persons or HSP.
HSP is a person who seem to experience sensations more intensely than others be it emotions, sounds, touch or light. Want to know if you are HSP? - take the test here. The traits, that is found in roughly 20% of the population, has been quite debated, especially due to lack of scientific evidence. Recently I heard that there is testing indicating if you have a more easily triggered nervous system which got me thinking about the phenomena that psychologist Elaine Aron has described as HSP. In my clinical practice I've also met people who seem to just experience things a bit more intensely than others.
So what do we know so far? Seems like there is actually scientific evidence that HSPs process and experience things a bit differently. A recent study shows that HSP brains responds to dopamine differently.
Dopamine is the brain's reward chemical. It's what makes you "want" to do certain things, and then feel a sense of victory or happiness when you do them.
Further more a 2014 study with functional brain imaging research found that HSPs had consistently higher levels of activity in key parts of the brain related to social and emotional processing. This higher level of activity kicked in even in tests involving strangers, showcasing HSPs' ability to extend compassion to people they don't personally know. (The effect was still highest with loved ones, however). The study also show that the attention and awareness when interacting with others is heightened for HSPs which could explain why HSPs sometimes find that kind of interaction overwhelming. Other brain studies show that HSPs emotional activation in the brain is higher than non-HSPs. A HSP’s brain is wired differently and the nervous system is highly sensitive with a lower threshold for action (2). This hyper-excitability contributes to increased emotional reactivity, a lower threshold for sensory information (e.g. bothered by noise, or too much light), and increased awareness of subtleties (e.g. quick to notice odors).'
When reading this I realised how well Compassion focused therapy responds to these difficulties as we practice how to downregulate the sympathetic nervous system and activating the calming parasympathetic nervous system. We also work with understanding and regulating emotions.
I hope there will be more studies in this area that can shed more light on the phenomena and hopefully also explore the link with self-criticism.
Aron, E.N., Aron, A., Jagiellowicz, J., 2012. Sensory processing sensitivity: a review in the light of the evolution of biological responsivity. Pers. Soc. Psychol. Rev.16 (3), 262–282.
Pluess, M., Boniwell, I., 2015. Sensory-processing sensitivity predicts treatment response to a school-Based depression prevention program evidence of vantage sensitivity. Pers. Ind. Differ. 82, 40–45.
Homberg, J.R., Schubert, D. Asan, E. & Aron, E.N. (2016). Sensory porcessing sensitivity and serotonin gene variance: Insights into mechanisms shaping environmental sensitivity. Neuroscience and Biobehavioral Reviews. 71, 472-483.