What Is Hyposensitivity?
Hypersensitivity refers to someone who experiences ‘too much’ sensory stimuli. So what is hyposensitivity? It’s the other side of the spectrum where individuals have diminished senses. In essence, they feel less through their senses than they should.
Hyposensitivity is a sensory processing difference or Sensory Processing Disorder (SPD). It’s also a neurological condition that affects the brain’s ability to process sensory input. People with hyposensitivity will experience some form of under-response from their senses. This can range across touch, smell, sight, sound, taste, internal bodily functions, and movement.
The effects of hyposensitivity can vary between people. For instance, some people may not respond to their names or find it difficult to notice smells. Others can be fidgety, clumsy, or always seek out sensory and movement experiences.
There is also an increased likelihood of having hyposensitivity or at least a sensory processing difference for people with autism. For instance, some people with autism can find that certain senses like smell and taste are over-responsive while others such as sounds or feelings may be under-responsive.
Low awareness levels and a general lack of understanding around hyposensitivity can lead to societal stigmas and judgements of the condition. This can lead to people who experience hyposensitivity hiding or masking their symptoms.
Hyposensitivity Symptoms
Hyposensitivity symptoms can vary but there are some general behaviours. For instance, people with hypersensitivity may be unable to sit still for long or respect others’ boundaries. They may struggle to detect feelings of hunger or pain and can pursue many sensory-seeking activities from their environments.
Hyposensitivity is a neurological condition and it changes how someone’s brain tracks sensory input. Because of this, symptoms can show up across some or all of a person’s senses. Some examples of these may include the following:
Tactile
- A compulsion to touch people or things to sense textures
- Clumsy and uncoordinated movements
- High pain tolerance or indifference
Proprioceptive
- Challenges in sensing body position or movements
- Difficulties with coordination and motor skills
Interoceptive
- Difficulties sensing internal signals from the body such as hunger or thirst
- May have problems knowing when to use the bathroom
Vestibular
- Lack of the usual sense of safety concerning body movements
- May indulge in spinning or swinging the body
Gustatory
- May prefer stronger tastes or have problems with certain food textures
- Can experience a need to lick inedible objects
- Difficulties with certain food textures
Olfactory
- Diminished reaction to or acknowledgement of certain smells
- May seek out strong or unpleasant smells
- May prefer stronger odours such as lemon, mint, and curry flavours
Visual
- Tires easily from intense reading or similar visual activities
- Can focus too much on patterns and details
- May be unresponsive to bright lights or visual stimuli
Auditory
- May find it difficult to filter out background or louder noises, listening to music and TV at louder volumes than is typical
- May seek out louder sounds or listen to music and TV at louder volumes
- Could risk damage to hearing from headphone use or putting ears too close to loud noises or speakers
Hyposensitivity and Autism
There’s a close connection between autism and hyposensitivity. Studies suggest around 90% of people with autism also have atypical sensory experiences, which can include hyper- and hypo-reactivities.
Despite the close links, sensory processing difficulties or Sensory Processing Disorder (SPD) is a separate condition from autism. To this end, not all people with SPD will have autism and not all people with autism will have sensory processing problems.
Autism exists on a spectrum. This means individuals across the autism spectrum can face difficulties with sensory processing problems. It’s also interesting to note that hypersensitivity is more prevalent in females with autism. Research also suggests sensory sensitivity can vary in individuals with autism, with the prevalence of SPD or sensory sensitivities ranging from between 69% to 96%.
Hyposensitivity vs Hypersensitivity
Hyposensitivity and hypersensitivity are two extreme ends that someone with sensory processing disorder may experience. In the former, sufferers can experience reduced sensitivity or under-sensitivity to stimulus. In the latter, people with this condition can feel over-sensitive to stimuli and may display some of the following traits:
- Avoiding overwhelming situations, smells, sounds, textures, and tastes
- Engaging in regular calming activities such as meditation, prayer, stillness, being alone
- Insisting on following routines and a resistance to any change
- A low pain tolerance
Sensory processing difficulties are very common in people with autism. But it’s also worth noting how people with autism can experience both hyposensitivity and hypersensitivity at the same time. When this happens, it’s likely that certain sensory functions under-respond–like auditory for example–while others over-respond–like visual or touch senses. This can make diagnosis more difficult especially when someone has autism.
Raising awareness and acceptance of SPD, hyposensitivity, hypersensitivity, and autism is key to ensuring people with symptoms of these conditions can lead fuller and more accepting lives.
Hyposensitivity Treatment
An occupational therapist, speech and language therapist, or a physiotherapist usually diagnose hyposensitivity. It will include evaluations, testing, and observations of responses to sensory stimuli.
Testing to diagnose SPD may include Sensory Integration and Praxis Tests. These tests assess abilities across vestibular, kinaesthetic, proprioceptive, tactile, and visual systems. Clinical observations are also conducted in a variety of settings.
Treatment for SPD or hyposensitivity may include sensory integration therapy. Developed in the 1970s, sensory integration therapy helps people to manage multiple sensory inputs. First aimed at supporting children to develop lifelong coping skills, therapy for hyposensitivity encourages movement, challenges fine and gross motor planning, and helps to develop adaptive behaviours to engage with the world.
While there is limited research on its effectiveness as a therapy, this type of therapy can make a positive difference for people with hyposensitivity, SPD, and autism. The range of interventions and treatments used may include the following:
- Balance-based treatments
- Therapies based on movements
- Exploring and arousing senses using textures, sounds, or cushions
- Art-based therapies
- Play-based treatments like obstacle courses, puzzles, trampolines, and scooters