There is a large and growing number of academic peer-reviewed papers that describe theories of sensitivity and report results of research studies on sensitivity.
Here we present the summaries of a few selected influential papers on sensitivity theories and the measurement of sensitivity.
Theories of Environmental Sensitivity
Biological sensitivity to context: I. An evolutionary-developmental theory of the origins and functions of stress reactivityDevelopment and Psychopathology, 17(2), 271-301.
This theoretical paper introduces the concept of Biological Sensitivity to Context, an evolutionary-developmental theory that describes how the quality of early life experiences shapes an individual’s level of sensitivity through the programming of their physiological stress reactivity.
According to this theory, particularly negative as well as especially positive childhood environments appear to be associated with greater physiological reactivity later in life.
In contrast, stress reactivity is lowest for individuals with childhood environments that were neither extremely beneficial nor extremely adverse.
Importantly, heightened physiological stress reactivity is then associated with increased sensitivity to both negative and positive experiences. The theory is supported by empirical studies which are reviewed.https://journals.sagepub.com/doi/10.1111/j.1467-8721.2008.00571.x
Vulnerability genes or plasticity genes?Molecular Psychiatry, 14(8), 746-754. doi: 10.1038/mp.2009.44
In this conceptual paper on gene-environment interaction, the authors propose that some genetic variants may reflect broad sensitivity to the environment rather than an inherent vulnerability for the development of psychological problems when exposed to adverse influences.
The authors refer to three well-known examples of vulnerability genes that have been associated with heightened risk for the development of antisocial behaviour, depression and attention deficit hyperactivity disorder.
In all three cases some studies show that people that carry the risk variants are not only more likely to develop problems when experiencing adversity but also less likely to develop problems when experiencing a supportive environment.https://www.nature.com/articles/mp200944
Beyond diathesis stress: differential susceptibility to environmental influencesPsychological Bulletin, 135(6), 885-908. doi: 10.1037/a0017376
This paper introduces the concept of Differential Susceptibility. It lays out the theoretical foundations and then reviews a large number of studies that provide empirical evidence for the concept.
According to Differential Susceptibility Theory, children differ fundamentally in their developmental response to environmental influences with some being more and some less sensitive.
Importantly, more susceptible individuals are not only more affected by the negative effects of adverse experiences but also particularly responsive to the positive effects of supportive experiences.
According to empirical studies susceptibility has been associated with specific genetic, physiological and behavioural factors which are reviewed in this paper.https://psycnet.apa.org/doiLanding?doi=10.1037%2Fa0017376
Differential susceptibility to the environment: an evolutionary—neurodevelopmental theoryDevelopment and Psychopathology, 23(1), 7-28. Doi: 10.1017/S0954579410000611
In this conceptual paper Environmental Sensitivity is discussed from an evolutionary-developmental perspective and in relation to the frameworks of Differential Susceptibility and Biological Sensitivity to Context.
Authors discuss similarities and differences between the two sensitivity theories and outline the neurobiological and physiological mechanisms of sensitivity in an attempt to integrate the two frameworks.
After summarising empirical evidence for individual differences in sensitivity, authors discuss methodological and statistical considerations for research on sensitivity as well as the practical implications of sensitivity for psychosocial interventions before suggesting an agenda for future research on Environmental Sensitivity.https://www.ncbi.nlm.nih.gov/pubmed/21262036
Sensory processing sensitivity: a review in the light of the evolution of biological responsivityPersonality and Social Psychology Review, 16(3), 262-282. doi: 10.1177/1088868311434213
This review paper covers the concept of Sensory Processing Sensitivity (SPS) and its four proposed components drawing on the scientific literature from various fields of research.
The paper reviews research on animal personality and suggests that sensitivity should be considered an evolutionary trait based on the observation that the trait has been found in many different species.
It then summarises research in humans, including work on infant temperament and personality traits in relation to sensitivity.
Finally, the review covers research on SPS, including the development of the HSP scale, the four facets of SPS and the relationships between SPS and personality traits before proposing directions for future researchhttps://journals.sagepub.com/doi/10.1177/1088868311434213
Vantage sensitivity: Individual differences in response to positive experiencesPsychological Bulletin, 139(4), 901-916. doi: 10.1037/a0030196
This paper introduces the concept of Vantage Sensitivity which is related to but different from Differential Susceptibility.
According to Vantage Sensitivity people differ significantly in their response to positive experiences: whereas some appear to benefit particularly strongly from positive experiences, others fail to do so.
Vantage Sensitivity differs from the related concept of Differential Susceptibility in that it only describes individual differences to positive experiences (it does not make predictions about the response to negative experiences).
Besides providing the theoretical foundation of the concept and delineating it from related constructs such as resilience, a range of studies are being reviewed that provide empirical evidence for Vantage Sensitivity.
These studies feature genetic, physiological and behavioural factors that have been shown to be associated with an increased responsivity to positive experiences.https://psycnet.apa.org/doiLanding?doi=10.1037%2Fa0030196
Individual Differences in Environmental SensitivityChild Development Perspectives, 9(3), 138-143. doi: 10.1111/cdep.12120
This theoretical paper describes the integration of all leading sensitivity theories into a single framework.
The resulting concept of Environmental Sensitivity represents an overarching meta-framework for individual differences in sensitivity to environmental influences that integrates the three leading theories on sensitivity (i.e., Sensory Processing Sensitivity, Differential Susceptibility, and Biological Sensitivity to Context) as well as the related frameworks of Vantage Sensitivity and Diathesis-Stress.
According to the concept of Environmental Sensitivity, people differ in their sensitivity due to individual differences in their ability to perceive and process information about the environment.
Furthermore, differences in Environmental Sensitivity are proposed to be associated with specific features of the central nervous system and influenced by both genetic and environmental factors.https://srcd.onlinelibrary.wiley.com/doi/abs/10.1111/cdep.12120
Sensory Processing Sensitivity in the context of Environmental Sensitivity: A critical review and development of research agendaNeuroscience and Biobehavioral Reviews, 98, 287-305. Doi: 10.1016/j.neubiorev.2019.01.009
This paper provides a detailed and extensive review of research on sensitivity.
The review covers information on the various sensitivity theories, how sensitivity is measured, and whether it is a continuous or categorical trait.
It also discusses the underlying mechanisms of sensitivity, its relation with personality and temperament, as well as its development over time.
Furthermore, the authors suggest future directions for research on sensitivity.
These suggestions include the development of more objective measures, investigation of the genetic and environmental factors that shape sensitivity, as well as research on the relation between sensitivity and mental health outcomes.https://www.ncbi.nlm.nih.gov/pubmed/30639671
Measures of Environmental Sensitivity
Sensory-processing sensitivity and its relation to introversion and emotionalityJournal of Personality and Social Psychology, 73(2), 345-368.
This is the first academic paper on the concept of Sensory Processing Sensitivity. It is based on seven separate empirical studies on sensitivity.
The main aim of the paper was to examine the relation between sensitivity and introversion as well as emotionality.
However, the main contribution of the reported work is the development of a valid measure to assess people’s individual level of sensitivity.
The results indicate that sensitivity can be reliably measured using the Highly Sensitive Person (HSP) scale which includes 27 questions.
Importantly, authors demonstrate that although sensitivity is significantly related to introversion and emotionality, it is a distinct and unique personality trait.https://www.ncbi.nlm.nih.gov/pubmed/9248053
Dandelions, tulips and orchids: evidence for the existence of low-sensitive, medium-sensitive and high-sensitive individualsTranslational psychiatry, 8(1), 24. doi: 10.1038/s41398-017-0090-6
This empirical paper provides evidence for the bi-factor structure of the 27-item HSP scale and tests for the existence of sensitivity groups in a series of adult samples.
Contrary to the widely held notion that 20% of the population fall into a highly sensitive group while the remaining 80% are characterised by lower sensitivity, the study reports the existence of three sensitivity groups.
About 30% of people tend to be “Orchids” with high sensitivity, and another 30% make up the “Dandelions” with low sensitivity, whilst about 40% with medium sensitivity fall between the other two groups and are described as “Tulips”.
According to further investigation of these groups, Orchids have lower extraversion and higher neuroticism compared to Dandelions whereas Tulips lay between the Orchids and Dandelions.https://www.nature.com/articles/s41398-017-0090-6
Environmental sensitivity in children: Development of the Highly Sensitive Child Scale and identification of sensitivity groups.Developmental Psychology, 54(1), 51-70. doi: 10.1037/dev0000406
This empirical paper describes the development of the Highly Sensitive Child (HSC) scale, a self-report measure of Environmental Sensitivity for children aged eight years and older.
The paper features five studies based on four different UK-based samples with a total of 3581 children and adolescents.
The psychometric properties of the new measure are reported as well as associations with related traits.
Finally, the paper investigates the existence of different sensitivity groups. Findings suggest that the HSC is a reliable and valid measure of Environmental Sensitivity in children and adolescents.
Furthermore, the paper reports the existence of three sensitivity groups: high (about 20 –35% of children), medium (about 41– 47%), and low (about 25–35%).https://psycnet.apa.org/doiLanding?doi=10.1037%2Fdev0000406
Observer-Rated Environmental Sensitivity Moderates Children’s Response to Parenting Quality in Early ChildhoodDevelopmental Psychology.
This empirical paper introduces the first observational measure of sensitivity for three-year-old children, the Highly Sensitive Child-Rating System (HSC-RS).
Overcoming limitations of questionnaires, the HSC-RS assesses sensitivity objectively with trained experts rating children’s behaviour in a series of standardised situations.
After describing the development of the measure, the authors test whether sensitivity measured with the HSC-RS predicts the relation between parenting quality and developmental outcomes.
Results suggests that more sensitive children are indeed more affected by both high and low parenting quality.
They are more likely to develop externalizing and internalizing problems when experiencing low parenting quality but also more likely to develop social competence when parents provide high quality parenting.https://www.ncbi.nlm.nih.gov/pubmed/31414847