Sensory defensiveness
Encyclopedia
Sensory defensiveness is a condition defined as having "a tendency to react negatively or with alarm to sensory input which is generally considered harmless or non-irritating" to neurotypical
persons.
It is not uncommon for individuals to have a few mild sensory defensive traits. However, when multiple defensive traits impact the person's day-to-day life, that person is considered to be sensory defensive.
Intolerance in this context should not always be taken as unwillingness to be subject to the sensory stimuli in question; rather, intolerance is an inability to process the sensory stimuli in any way other than as over-stimulating, because the sensory stimuli provokes a fight-or-flight reaction. This is also known as sensory overload
.
Sensory defensiveness can vary between individuals:
for sensory defensiveness, including genetic factors
, environmental conditioning, drug
or alcohol abuse
, sexual abuse
, or premature birth
. Those diagnosed with attention deficit hyperactivity disorder report much higher than average rates of hypersensitivity to sensory stimulus. Autism
also increases hypersensitivity, especially to sound. Additionally, stress of any kind usually increases sensitivity to sensory stimuli. Stress due to reactions to sensory input can cause a chain reaction, leading to a meltdown, as described below.
can lead to what is commonly termed a "meltdown". This may look much like a tantrum
, or a person may undergo dissociation, which causes him/her to withdraw into himself/herself. Individuals will often cope with their sensory difficulties by avoiding those situations that cause them irritation. Occupational therapists often prescribe "sensory diets". This is a therapy that is tailored to the individual in which he/she gets to experience calming sensory stimuli that help to balance his/her sensory system. Snoezelen
rooms, in which sensory experiences can be controlled and explored, are sometimes used. Individuals will often naturally create or find their own calming sensory stimuli (stims
) or sensory diets.
The other side to these issues is that many people report a positively heightened awareness of their senses, under the right conditions. They also promote "stims", which can include music, exercise, and any other pleasing sensory stimulation, as natural means of reducing stress.
. Sensory integration dysfunction is considered a symptom of the autism spectrum
, but a person does not have to display other autistic traits to have sensory defensiveness or sensory integration dysfunction. Sensory integration dysfunction and defensiveness are also common with developmental dyspraxia, cerebral palsy
, and fetal alcohol syndrome
.
Neurotypical
Neurotypical is a term that was coined in the autistic community as a label for people who are not on the autism spectrum: specifically, neurotypical people have neurological development and states that are consistent with what most people would perceive as normal, particularly with respect to...
persons.
It is not uncommon for individuals to have a few mild sensory defensive traits. However, when multiple defensive traits impact the person's day-to-day life, that person is considered to be sensory defensive.
Symptoms
Common symptoms of sensory defensiveness include intolerance of high-pitched noises, intolerance of chewing sounds, intolerance of overhead lights (especially fluorescent lighting); experiencing a feeling of being attacked upon being touched (especially from light touch or sudden touch); intolerance of certain types of fabrics in contact with the skin; becoming nauseated upon smelling something that does not smell bad to neurotypical individuals; difficulty maintaining eye-contact; severe intolerance of foods due to taste, texture, or temperature; and generally becoming overwhelmed when exposed to a lot of sensory stimuli at once.Intolerance in this context should not always be taken as unwillingness to be subject to the sensory stimuli in question; rather, intolerance is an inability to process the sensory stimuli in any way other than as over-stimulating, because the sensory stimuli provokes a fight-or-flight reaction. This is also known as sensory overload
Sensory overload
Sensory overload , related to Cognitive load in general, is a condition where one or more of the senses are strained and it becomes difficult to focus on the task at hand...
.
Sensory defensiveness can vary between individuals:
- The senses that are problematic for one person may not be so for another. (Commonly, individuals report major issues with two or three senses and minor issues with the other senses.)
- How easily and the way in which a particular sense bothers individuals varies (e.g. high-pitched noises may annoy someone, or they may hurt his/her ears; touch may provoke anxiety, or it can be painful).
- The triggers for a particular sense vary between people (e.g. one person may be sensitive to the texture of mushy foods, while another may be sensitive to crunchy foods).
Causes
There are believed to be multiple etiologiesEtiology
Etiology is the study of causation, or origination. The word is derived from the Greek , aitiologia, "giving a reason for" ....
for sensory defensiveness, including genetic factors
Human genetics
Human genetics describes the study of inheritance as it occurs in human beings. Human genetics encompasses a variety of overlapping fields including: classical genetics, cytogenetics, molecular genetics, biochemical genetics, genomics, population genetics, developmental genetics, clinical genetics,...
, environmental conditioning, drug
Drug abuse
Substance abuse, also known as drug abuse, refers to a maladaptive pattern of use of a substance that is not considered dependent. The term "drug abuse" does not exclude dependency, but is otherwise used in a similar manner in nonmedical contexts...
or alcohol abuse
Alcohol abuse
Alcohol abuse, as described in the DSM-IV, is a psychiatric diagnosis describing the recurring use of alcoholic beverages despite negative consequences. Alcohol abuse eventually progresses to alcoholism, a condition in which an individual becomes dependent on alcoholic beverages in order to avoid...
, sexual abuse
Sexual abuse
Sexual abuse, also referred to as molestation, is the forcing of undesired sexual behavior by one person upon another. When that force is immediate, of short duration, or infrequent, it is called sexual assault. The offender is referred to as a sexual abuser or molester...
, or premature birth
Premature birth
In humans preterm birth refers to the birth of a baby of less than 37 weeks gestational age. The cause for preterm birth is in many situations elusive and unknown; many factors appear to be associated with the development of preterm birth, making the reduction of preterm birth a challenging...
. Those diagnosed with attention deficit hyperactivity disorder report much higher than average rates of hypersensitivity to sensory stimulus. Autism
Autism
Autism is a disorder of neural development characterized by impaired social interaction and communication, and by restricted and repetitive behavior. These signs all begin before a child is three years old. Autism affects information processing in the brain by altering how nerve cells and their...
also increases hypersensitivity, especially to sound. Additionally, stress of any kind usually increases sensitivity to sensory stimuli. Stress due to reactions to sensory input can cause a chain reaction, leading to a meltdown, as described below.
Effects and treatment
Sensory overloadSensory overload
Sensory overload , related to Cognitive load in general, is a condition where one or more of the senses are strained and it becomes difficult to focus on the task at hand...
can lead to what is commonly termed a "meltdown". This may look much like a tantrum
Tantrum
A tantrum is an emotional outburst, usually associated with children or those in emotional distress, that is typically characterized by stubbornness, crying, screaming, yelling, shrieking, defiance, angry ranting, a resistance to attempts at pacification and, in some cases, violence...
, or a person may undergo dissociation, which causes him/her to withdraw into himself/herself. Individuals will often cope with their sensory difficulties by avoiding those situations that cause them irritation. Occupational therapists often prescribe "sensory diets". This is a therapy that is tailored to the individual in which he/she gets to experience calming sensory stimuli that help to balance his/her sensory system. Snoezelen
Snoezelen
Snoezelen or controlled multisensory Environment relates to the interdependence of both the space and the "client-centered" approach of the practitioner...
rooms, in which sensory experiences can be controlled and explored, are sometimes used. Individuals will often naturally create or find their own calming sensory stimuli (stims
Stimming
Stimming is a repetitive body movement, such as hand flapping, that is hypothesized to stimulate one or more senses. The term is shorthand for self-stimulation. Repetitive movement, or stereotypy, is often referred to as stimming under the hypothesis that it has a function related to sensory input....
) or sensory diets.
The other side to these issues is that many people report a positively heightened awareness of their senses, under the right conditions. They also promote "stims", which can include music, exercise, and any other pleasing sensory stimulation, as natural means of reducing stress.
Component of other disorders
Sensory defensiveness is a subset of sensory integration dysfunctionSensory Integration Dysfunction
Sensory integration dysfunction is a neurological disorder characterized by a neurological sensory integration deficit. The more current diagnostic nosology uses the term sensory processing disorder to describe this condition....
. Sensory integration dysfunction is considered a symptom of the autism spectrum
Autism spectrum
The term "autism spectrum" is often used to describe disorders that are currently classified as pervasive developmental disorders. Pervasive developmental disorders include autism, Asperger syndrome, Childhood disintegrative disorder, Rett syndrome and Pervasive Developmental Disorder Not Otherwise...
, but a person does not have to display other autistic traits to have sensory defensiveness or sensory integration dysfunction. Sensory integration dysfunction and defensiveness are also common with developmental dyspraxia, cerebral palsy
Cerebral palsy
Cerebral palsy is an umbrella term encompassing a group of non-progressive, non-contagious motor conditions that cause physical disability in human development, chiefly in the various areas of body movement....
, and fetal alcohol syndrome
Fetal alcohol syndrome
Fetal alcohol syndrome is a pattern of mental and physical defects that can develop in a fetus in association with high levels of alcohol consumption during pregnancy. Current research also implicates other lifestyle choices made by the prospective mother...
.
Further reading
- Bogdashina, Olga. Sensory Perceptual Issues in Autism and Asperger's Syndrome: Different Sensory Experiences, Different Perceptual Worlds. An overview of sensory traits in the autism spectrum.
- Heller, Sharon. Too Loud, Too Bright, Too Fast, Too Tight: What to Do If You Are Sensory Defensive in an Overstimulating World (ISBN 0-06-093292-9)
- Moore, Karen. The Sensory Connection Program: Activities in Mental Health Treatment. Symptoms, background information, and treatment of Sensory Defensiveness in adults
- Wilbarger, Patricia and Julia. Sensory Defensiveness in Children Aged 2–12: An Intervention Guide for Parents and Other Caretakers. Explains the roots of sensory defensiveness in children.
- Separating Fact from Fiction in the Etiology and Treatment of Autism - A Scientific Review of the Evidence
- Why "Sensory Integration Disorder" Is a Dubious Diagnosis