Defining the concept
High sensitivity, introduced in the academic literature as Sensory Processing Sensitivity (SPS) (Aron & Aron, 1997) is an innate trait that approximately 15-20% of the world’s population has. This trait is characterized by a high sensitivity of the central nervous system, a deep processing of internal and external stimuli, and a tendency in the cognitive style to process information more elaborately (Aron, Aron, & Jagiellowicz, 2012).
Elain Aron (2004), who started the research in this field, has conceptualized a model that defines this concept from 4 perspectives – the DOES model:
- D – deep processing: information is processed more deeply,
- O – overstimulation: the tendency of being overwhelmed by the quantity of information that they encounter,
- E – emotional reactivity/empathy: the empathy they display, the emotional reactivity as a feedback to other people feelings
- S – subtleties: the nuances and details they perceive.
Although initially it was recognized in a limited number of species, nowadays it is considered that SPS is characteristic to members of more than 100 non-human species (Wolf, van Doorn, & Weissing, 2008). The concept of sensory processing sensibility adopted the biological perspective, which states that for most species there are different personality types – shy or bold members, aggressive or nonaggressive, sensitive or not sensitive (Sih & Bell, 2008).
Regarding highlysensitivity, researchers have focused on sensorial thresholds, that proved to be very low for individuals with this trait. Hipersenzitive people are described as more attentive and able to observe effortlessly subtle stimuli in their environment. Also, it is hard for them to ignore certain characteristics that may be irrelevant and they are easily annoyed by strong inputs, like loud sounds or high temperatures (Aron, 2010).
There has been defined a certain senzitivity towards environment, an ability to register and process information related to the context that people develop in – these characteristics help the person to react and adapt to the challenges and the opportunities associated with the environment (Pluess, 2015). Although adaptation is present for the great majority of individuals, studies suggest that there are large differences in the matter of environment senzitivity (Belsky & Pluess, 2013). This sensitivity may interfere with participation in activities, as well as social, cognitive or sensorial and motor development for children (Dunn, 2001).
At the neuronal level, fMRI studies revealed that SPS is correlated with a greater general activation for the visual areas associated with fine distinctions (Jagiellowicz et al., 2010) and in the regions responsible with consciousness, empathy, feedback to other people emotional expressions (Avecedo et al., 2014).
Differences between SPS and similar traits
SPS is comparable at a behavioral level with traits that are identified by the pause between actions – inhibition (Kagan et al., 1994), shyness (Jones et al., 1996) and introversion (Aron & Aron, 1997). Research and hipersenzitive people describing their experiences reveal that processing any type of input is more complex, so the decisions these persons make and their actions appear after a longer time, comparing to others. This is an aspect that can be assigned to inhibition, but the difference is that the inhibited persons have this type of behaviors such as delays or even lack of actions only for stimuli that they find negative (Jagiellowicz, Aron, și Aron, 2012).
Introversion was correlated with reflexivity and a thoughtful cognitive processing (Patterson et al., 1987), that are a part of the behavior of a hipersenzitive person, but the difference is their sociability – highly sensitive people are not characterized by a low sociability (Aron et al., 2010).
Autism spectrum disorders represent another category that highly sensitive children can be wrongly assigned to because of some common features of the two concepts. Children with autism spectrum disorders can be hyperactive in their interactions with tactile, visual or audio stimuli, but they also present some specific behaviors – repetitive actions, limited interests, difficulties in socialization and lack of empathy – that are not common for highly sensitive children.
SPS and the environment where children grow up and develop
Aron et al. (2005) discovered that a negative childhood environment has been associated with negative affectivity for highly sensitive people, the environment concept including parental practices and attitudes and also childhood experiences. Children with a temper considered more difficult were negatively affected by low quality parental practices and positively affected by high quality practices, compared to children with a less difficult temper, as teachers reported having in mind the social abilities of the children (Roisman et al., 2012).
Similar results have been obtained in another study where negative emotionality measured every 7 months has been associated with a high sensitivity, for both weak and strong mother-child relationships measured at 15 months old(Kim & Kochanska, 2012).
The study conducted by Pluess and Belski in 2010 showed that the baby’s temper reported by the mother at 6 months old was a predictor for the child’s sensitivity, considering the quality of parenting provided in the first 4-5 years of life.
The high level of stimulation that hipersenzitive children experience causes them distress starting from small ages, as excessive crying of very young children has been correlated with this feature of hipersenzitivity (Boterberg & Warreyn, 2016). Children that had a high level of reactivity were more prone to get sick or injured than those with a low reactivity, in stressful situations at home or at school and also in situations with a normal level of stress (Boice et al., 1995).
Aron, Aron and Davies (2005) showed that sensory processing sensitivity and unfavorable environmental childhood conditions lead to negative affectivity that can also lead to shyness in adulthood. This fear of negative evaluations from others in social interactions creates discomfort and a wish to limit this interactions, as well as anxiety and depression.
Liss, Timmel, Baxley and Killingsworth (2005) showed that sensory processing sensitivity was correlated with excessive parental protection. Parents that recognized their children’s sensitivity took over their tasks, leaving them without responsabilities and strengthening their perception of sensibility.
Taking into account all this information about the intense experiences of highly sensitive children and the effects that these experiences have on their activities, it is important that this innate trait could be identified from early ages, as it could become a protective factor, but also a risk factor for emotional problems and maladaptative behaviors for the adult period. As it was shown, both familial and scholar environments have contributions for the optimal development of the children, which implies the cooperation between parents and teachers. The people who interact with highly sensitive children should be able to properly identify them in order to be able to support them emotionally and to adapt the environmental conditions accordingly to their capacities of processing stimuli at a level that is not overwhelming for them.
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This article has been published in the Journal of Clinical Psychology and Psychotherapy, issue no 5-6, 2018, on the www.expertpsy.ro website and it was presented in the Conference ASISTENȚA LOGOPEDICĂ: ACTUALITATE ȘI ORIZONTURI, at Chișinău, 22-23 November 2018 and it was posted on the blog with the consent of the authors, co-organizing the E-MOTION project.