Sensory Processing Sensitivity SPS was defined by the American psychologists Elaine and Arthur Aron in the 1990’s as a personality trait characterised by heightened sensitivity of the central nervous system, resulting in deeper cognitive processing of sensory information and greater risk for overstimulation.

The early work on SPS included the development of the Highly Sensitive Person HSP scale with 27 items. The latter was recently revised to encompass six subscales (HSP-R).

Initially, a Highly Sensitive Person was characterized by four specific aspects:

1) greater depth of processing (i.e., the tendency to process information more deeply);

2) overstimulation (i.e., the proclivity to be easily overstimulated);

3) emotional reactivity (i.e., stronger emotional reactions to experiences, and in social contexts, greater empathy, so this aspect needed dividing), and

4) sensitivity to subtle stimuli (i.e., heightened sensory sensitivity).

Over recent years, empirical research has provided evidence for additional aspects of sensitivity, such as

5) sensitivity to positive experiences and

6) sensitivity to social cues.

Other researchers have used various other terms to denote this responsiveness to stimuli. Whilst various individuals have continued to research around SPS – in particular Prof. Michael Pluess and colleagues at sensitivityresearch.com – the concept remains academically controversial.

According to a source on Wikipedia, the Big Five (the most widely accepted personality model in psychology) “accounted for only 28% of the variance, i.e. differences between individuals, in the trait of high sensitivity .” This means that personality, as an explanatory framework, is insufficient to account for the concept of high sensitivity…

To learn more about the concepts of Sensory Processing Sensitivity or Highly Sensitive Person (HSP) according to Elaine Aron: hsperson.com

Evolution of the concept of sensory processing sensitivity and its measurement: The Highly Sensitive Person scale-revised

You may also like the definitions of Sense and Sensitivity, as well as the article Meanings of Sense and Sensitivity.