A highly sensitive person (HSP) is a neurodivergent individual who is thought to have an increased or deeper central nervous system sensitivity to physical, emotional, or social stimuli. Some refer to this as having sensory processing sensitivity, or SPS for short. While highly sensitive people are sometimes negatively described as being “too sensitive," it is a personality trait that brings both strengths and challenges. The term highly sensitive person was first coined by psychologists Elaine Aron and Arthur Aron in the mid-1990s. Elaine Aron published her book, "The Highly Sensitive Person," in 1996, and interest in the concept has continued to grow since then. HSP isn't a clinical diagnosis in the DSM, but many people identify with the descriptor. Empathy is a spectrum, like many qualities, and can cause difficulty if too high or too low. While neither is automatically bad, high empathy can be exhausting.
About one in every five people scores high on measures of SPS – too many to consider it a disorder, but few enough that highly sensitive people often feel “different” from the majority. Importantly, being an HSP is not a diagnosis or pathology. It’s a personality trait or “temperamental disposition” – much like introversion or extraversion – and it comes with both advantages and challenges. High sensitivity should also not be confused with sensory processing disorder (SPD), which is a clinical condition; HSPs generally have well-functioning senses, they just process sensory input more intensely. In fact, researchers have identified SPS as an innate trait with a genetic basis and documented it in over 100 species (from fruit flies to humans), indicating that a cautious, sensitive approach to stimuli can be evolutionarily adaptive in certain environments.
Dr. Elaine Aron describes a highly sensitive person as someone who “has a sensitive nervous system, is aware of subtleties in [their] surroundings, and is more easily overwhelmed when in a highly stimulating environment”. HSPs often recall feeling different even as children – perhaps they were the kid who was easily startled by loud noises, moved by music or art, or deeply upset by criticism or cruelty to others. Many HSPs are naturally empathetic, intuitive, and conscientious. However, without understanding their trait, they might grow up being mislabeled as “shy,” “anxious,” or “too emotional.” Recognizing SPS as a real, normal trait can be a huge relief for HSPs. It gives a framework to understand why they feel the way they do and how they can leverage their sensitivity in positive ways.
The Nature of Sensory Processing Sensitivity
Sensory Processing Sensitivity is characterized by a deep processing of information and a heightened awareness of the environment. While it is not a disorder, it is an innate trait with a genetic basis. Research indicates that approximately 20 percent of the population may be highly sensitive. More recent research suggests that there may be three groups of sensitive people. About 40 percent of people in this framework fall into a moderately sensitive group (tulips). Low-and high-sensitive individuals each make up about 30 percent of individuals. Research appears to be pointing to sensitivity as a continuum rather than having definitive categories.
The trait is distinct from introversion or neuroticism. Though often overlapping with these traits, high sensitivity is a separate and biologically rooted temperament. HSPs are often negatively described as “too sensitive.” But being an HSP isn’t a bad thing. Like any personality trait, it comes with challenges, but also many strengths. For example, highly sensitive people tend to excel at creativity, empathy, and the ability to notice things that others miss or make connections that others do not see. In fact, according to Linda Silverman, the director of the Gifted Development Center, high sensitivity is linked to giftedness.
Distinguishing SPS from Sensory Processing Disorder
A critical distinction in the field of sensory processing is the difference between Sensory Processing Sensitivity (SPS) and Sensory Processing Disorder (SPD). It should not be confused with sensory processing disorder (SPD), wherein the brain has difficulty organizing and processing sensory stimuli. SPS, in comparison, is not associated with dysregulation, but with awareness, depth of processing, and needing time to process information and stimuli. SPS is not a disorder, but rather an innate trait. It should not be confused with sensory processing disorder (SPD), wherein the brain has difficulty organizing and processing sensory stimuli. High sensitivity should also not be confused with sensory processing disorder (SPD), which is a clinical condition; HSPs generally have well-functioning senses, they just process sensory input more intensely.
Core Characteristics of the HSP Trait
While every individual is unique, highly sensitive people tend to share a set of core characteristics. Dr. Elaine Aron uses the acronym "D.O.E.S." to summarize the four key features of the HSP trait: Depth of processing, Overstimulation, Emotional reactivity (including high empathy), and Sensitivity to subtleties.
Depth of Processing
HSPs process information more deeply and thoroughly than others. They don’t just notice more – they think more about what they notice. Sensitive individuals have a rich inner life, often spending time reflecting on experiences, pondering meanings, and making connections. This depth of processing means that HSPs may need more time to make decisions or respond to questions, as they are internally reviewing many variables and potential outcomes.
Overstimulation
Because HSPs process stimuli more deeply, they are more easily overwhelmed when in a highly stimulating environment. This can manifest as a need to withdraw from social situations or noisy environments to regain equilibrium. The threshold for overstimulation varies among individuals, but the underlying mechanism is the same: the central nervous system is processing a high volume of information, leading to fatigue or stress.
Emotional Reactivity and Empathy
This is the emotional responsiveness to other people. HSPs tend to experience other people’s emotions. High empathy can be a strength, allowing for deep connections and understanding, but it can also be exhausting. HSPs are often deeply affected by other people’s moods. They may also be easily startled or experience heightened nervousness when being observed performing a task.
Sensitivity to Subtleties
HSPs are aware of subtleties in their surroundings. This can include a sensitivity to bright lights, strong smells, loud noises, clothing materials, and other stimuli. They may also be sensitive to caffeine. While they may appreciate pleasant stimuli like music, scent, and scenery (associated with aesthetic sensitivity), they are also more prone to discomfort with loud noises, which is associated with a low sensory threshold.
The HSP Scale and Measurement
Dr. Elaine Aron, a clinical research psychologist who coined the term “the highly sensitive person,” also developed a now widely used scale that measures responses to different stimuli. According to the scale, some markers of highly sensitive people (HSPs) include: - Needing to withdraw (privacy from stimulation) - Being easily overwhelmed by bright lights, strong smells, loud noises, clothing materials, and other stimuli - Being affected by other people’s moods - Feeling annoyed or overwhelmed when asked to do too many things at once - Becoming nervous when observed performing a task - Sensitivity to caffeine
A Highly Sensitive Child Scale is also available and used. This scale divides behaviors into three distinct components of SPS. Discomfort with loud noises, for example, is associated with a low sensory threshold. Nervousness when having to do multiple tasks in a short amount of time is linked to ease of excitation. Responding to pleasant stimuli, like music, scent, and scenery, is associated with aesthetic sensitivity.
Prevalence and Origins
Early studies estimate that 20 percent of the population may be “highly sensitive.” Researchers sometimes refer to highly sensitive people as orchids, given the flower’s responsiveness to changes in its environment. Less sensitive people, on the other hand, are referred to as dandelions. Highly sensitive people make up about 30 percent of the population.
The trait has gained recognition through Aron’s work, including her 1996 book "The Highly Sensitive Person," and hundreds of studies since have examined how high sensitivity influences brain activity, health, and behavior. The term Highly Sensitive Person (HSP) was introduced by psychologist Elaine Aron in the mid-1990s to describe individuals with heightened sensitivity to physical, emotional, and social stimuli. In literature, HSP is often referred to as sensory processing sensitivity (SPS), which is not to be confused with sensory processing disorder, a condition that affects how the brain processes sensory information. HSP is not a disorder but a personality characteristic found in about 15–20% of the population.
Experiences of Highly Sensitive Persons
So, what does it actually feel like to have high SPS? Dr. Aron describes a highly sensitive person as someone who “has a sensitive nervous system, is aware of subtleties in [their] surroundings, and is more easily overwhelmed when in a highly stimulating environment”. HSPs often recall feeling different even as children – perhaps they were the kid who was easily startled by loud noises, moved by music or art, or deeply upset by criticism or cruelty to others.
Violence and Distress
It is typical to dislike violence, but for HSPs, they are likely to be more distressed or deeply disturbed by violence. Even hearing about violence or cruelty can be extremely upsetting for them. HSPs will likely make effort to avoid situations where they may witness violence such as avoiding certain movies, TV shows, or hearing stories of animal cruelty. This deep emotional responsiveness is a hallmark of the trait.
Social and Emotional Challenges
Without understanding their trait, HSPs might grow up being mislabeled as “shy,” “anxious,” or “too emotional.” The experience of being easily overwhelmed by stimuli or needing to withdraw can be misinterpreted by others as antisocial behavior or weakness. However, recognizing SPS as a real, normal trait can be a huge relief for HSPs. It gives a framework to understand why they feel the way they do and how they can leverage their sensitivity in positive ways.
Clinical Considerations and Misconceptions
It is important for mental health professionals and individuals to understand that SPS is not a pathology. It is a temperament. However, the challenges associated with high sensitivity can overlap with symptoms of anxiety or other conditions. For example, the ease of excitation component of SPS can look like anxiety when an individual becomes nervous when asked to do too many things at once or when observed performing a task.
Distinguishing from Other Traits
SPS is distinct from sensory processing disorder and should not be confused with introversion or neuroticism. Though often overlapping with these traits, Aron emphasized that high sensitivity is a separate and biologically rooted temperament. Understanding this distinction is crucial for accurate self-assessment and for clinicians to avoid misdiagnosis.
The Continuum of Sensitivity
Research appears to be pointing to sensitivity as a continuum rather than having definitive categories. This framework helps normalize the experience of sensitivity. It suggests that sensitivity is not an "all or nothing" trait but a variation in how the nervous system responds to the environment. This perspective aligns with the view that high sensitivity is a normal, healthy personality trait, although one that — like all personality traits — comes with its own advantages and drawbacks.
Conclusion
Highly Sensitive Person (HSP) is a term used to describe individuals with Sensory Processing Sensitivity (SPS), a neurodivergent trait characterized by a deeper central nervous system sensitivity to stimuli. Affecting approximately 15 to 30 percent of the population, SPS is an innate, genetically based temperament, not a disorder. It is distinct from clinical conditions such as Sensory Processing Disorder (SPD), which involves difficulty organizing sensory information, whereas SPS involves intense but functional processing. The trait is often summarized by the acronym D.O.E.S., representing Depth of processing, Overstimulation, Emotional reactivity (including high empathy), and Sensitivity to subtleties. HSPs often experience heightened awareness of subtleties, deep emotional responsiveness, and a greater need for downtime to process information. While the trait presents challenges, such as susceptibility to overstimulation and distress from violence, it also confers strengths including creativity, empathy, and the ability to make connections others might miss. Recognizing SPS as a normal variation in human temperament is essential for reducing stigma and enabling individuals to understand their unique needs.