Highly sensitive person

The term Highly Sensitive Person (HSP) was coined by Dr. Elaine N. Aron, a research psychologist and psychotherapist who self-identifies as an HSP. She wrote the book The Highly Sensitive Person: How to Thrive When the World Overwhelms You as a guide for HSPs and non-HSPs alike to better understand this type of sensitivity.

HSPs are easily affect by sensory stimuli, whether internal (such as hunger, pain, or tiredness) or external (such as music, light, or conversation). Carl Gustav Jung originally called the HSP disposition innate sensitiveness and stated that "events bound up with powerful impressions can never pass of without leaving some trace on sensitive people." Periods of arousal and overstimulation of the nervous system are often remedied by solitude.

According to Dr. Aron, highly sensitive people constitute ~15-20% of the population. They process sensory data much more deeply and thoroughly because their nervous systems are biologically different. In fact, body fluids of HSPs tested higher for norepinephrine and cortisol than non-HSPs. Furthermore, research on both animals and humans has revealed that the sensitivity experienced by HSPs is innate in most cases.

This is a specific trait with key effects that have often been confused with shyness, inhibition, fearfulness, introversion, as well as other social misconceptions. HSPs often contend with negative attitudes toward sensitivity in the United States that result from living in a society which generally prizes extroverted, outgoing behavior; this is in contrast to 'shy' dispositions that are generally valued in China.

HSPs are generally considered to:

Have a keener eye for detail and accuracy
Be highly aware of themselves and their environment
Concentrate more deeply
Meta thinking
Internalize others' moods and emotions for deeply
Have finer motor skills
Be more affected by caffeine
Be more "right-brained"
Have a rich inner life
Need more rest
React more intensely to medication

References

↑ Ketay, S., Hedden, T., Aron, A., Aron, E., Markus, H., & Gabrieli, G. (2007, January). The personality/temperament trait of high sensitivity: fMRI evidence for independence of cultural context in attentional processing. Poster presented at the annual meeting of the Society for Personality and Social Psychology, Memphis, TN. Summary by Aron (2006): "A functional study comparing brain activation in Asians recently arrived in the United States to European-Americans found that in the nonsensitive, different areas were activated according to culture during a difficult discrimination task known to be affected by culture, but culture had no impact on the activated areas for highly sensitive subjects, as if they were able to view the stimuli without cultural influence."
↑ Brodt, S., Zimbardo, P. "Modifying Shyness-Related Social Behavior Through Symptom Misattribution" Journal of Personality and Society Psychology 41 (1981): 437-49.

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[1] Ketay, S., Hedden, T., Aron, A., Aron, E., Markus, H., & Gabrieli, G. (2007, January). The personality/temperament trait of high sensitivity: fMRI evidence for independence of cultural context in attentional processing. Poster presented at the annual meeting of the Society for Personality and Social Psychology, Memphis, TN. Summary by Aron (2006): "A functional study comparing brain activation in Asians recently arrived in the United States to European-Americans found that in the nonsensitive, different areas were activated according to culture during a difficult discrimination task known to be affected by culture, but culture had no impact on the activated areas for highly sensitive subjects, as if they were able to view the stimuli without cultural influence."

[articles-2] Brodt, S., Zimbardo, P. "Modifying Shyness-Related Social Behavior Through Symptom Misattribution" Journal of Personality and Society Psychology 41 (1981): 437-49.