Hyposensitivity and hypersensitivity often get mixed up. Both are types of sensory processing disorders, but many people use them interchangeably and think they mean the same thing. In reality, they don’t. It’s easy to confuse them, as they sound so similar. However, while hypersensitivity results in a person experiencing overstimulation, hyposensitivity results when a person experiences little to no response from a stimulus.
In other words, a person with hyposensitivity will experience low levels or an absence of sensory feedback. For example, someone with hyposensitivity may not experience feelings of being hot, cold, or in pain the same way other people would. On the other hand, those with hypersensitivity may experience extreme feelings of being hot, cold, or pain.
Hyposensitivity and Autism
People with autism spectrum disorder (ASD) often have sensitivities to things like visuals, smells, sounds, touch, tastes, balance, awareness of both body positions and movements, and internal body cues and sensations. Most individuals with ASD have a mixture of both over- and under-responsiveness. These two conditions are known as hypersensitivity and hyposensitivity sensory processing disorder, respectively.
People with ASD may be over-responsive to certain types of lights, such as bright lights and lights that produce certain wavelengths. For example, individuals experiencing symptoms of ASD may respond negatively to fluorescent and LED lights. Many individuals with ASD, who experience this type of response, tend to engage in sensory avoidance. That is, they will do their best to avoid overwhelming stimuli. A person with ASD having hypersensitivity to bright lights may cover their eyes to avoid such lights.
Hyposensitivity in people with ASD differs from hypersensitivity. Instead of being overwhelmed by stimulus, people with hyposensitivity experience underwhelming feelings, resulting in them needing to constantly explore textures with their hands and seeking out more sensory information from the world around them. People with hyposensitivity may also have difficulty distinguishing sensations, including feelings of hunger and illness.
Hyposensitivity and Other Concerns
Sensory processing disorders (SPDs), such as hyposensitivity, have been linked to ASD, and many people with ASD experience SPD. However, it's important to note that not everyone with SPD has ASD. This means that people with SPD may have SPD independently from other disorders, such as ASD, though it's unknown what other causes or links exist.
The exact cause of SPD is unknown, but some believe that genetics play a role in who will experience SPD. Furthermore, some doctors consider ASD a parent disorder to SPD and believe that ASD adults will pass SPD on to their children.
Because the exact cause of SPD is unknown, there are no ways to prevent SPD from occurring.
Hyposensitivity Symptoms
Symptoms of hyposensitivity can be categorized as auditory, olfactory, visual, and vestibular.
Auditory hyposensitivity refers to a lack of stimulation from sounds. As a result, one may be able to withstand loud sounds and experience the following:
- No response to name being called
- Enjoys sound-making activities
- Requires frequently repeated verbal directions
- Confusion with localizing sounds
- Turning up the sound settings of devices to maximum volume
Olfactory means our sense of smell. So, olfactory hyposensitivity reveals itself as a high tolerance and an under-responsiveness for smells:
- Craving foods that have strong smells
- High threshold for unpleasant smells
- Sniff people and objects to interact with them
- Trouble telling the difference between various smells
Visual hyposensitivity is related to what we see and process visually. One is likely to be under-responsive to visual situations and inputs and may experience:
- Trouble with puzzles, pictures, objects, and words
- Difficulty locating specific items amid other items
- Issues with tracking items visually, such as a ball being thrown
- Difficulty with depth perception and items that have little to no contrast
Finally, the vestibular system is responsible for the input we receive from our ear and how we register it in contrast to equilibrium, sense of movement, gravitational changes, and more. If one has vestibular hyposensitivity, they may experience:
- Being able to spin for long periods of time without getting dizzy
- Being able to find enjoyment when swinging for a longer duration
- Intense enjoyment for rollercoasters and other adrenaline-inducing activities
- Enjoying rocking in place when sitting stationary
- Enjoying being tossed in the air or having your feet suspended
- Enjoying rocking and nodding your head back and forth
Other general symptoms of hyposensitivity include:
- Being clumsy
- Fidgeting
- Trouble with personal boundaries
- Issues with realizing your own strength
- Indifference to pain and temperature
- A constant need to touch others, even when it’s inappropriate
- Failure to understand personal space
- Inability to sit still for long periods of time
- Enjoying activities that consist of jumping, bumping, and crashing
- Enjoying deep pressure, including tight-holding bear hugs
- Loving intense movements
Hyposensitivity Treatment
It’s important to treat and make accommodations for people with ASD and who are experiencing hyposensitivity. Some accommodations that can be made for then include:
- Offering visual supports
- Providing access to sensory tools such as fidget toys
- Arranging furniture to give individuals a safer environment
- Allowing for frequent movement breaks
- Providing foods with strong flavors, different textures, and strong smells
- Offering weighted blankets, deep-pressured clothes, and lap pads
There are also certain therapies that may help with hyposensitivity. Sensory integration therapy is provided to those with sensory processing disorders. It helps children adjust to sensory regulation through movement and physical contact.
Sensory integration therapy often occurs in a sensory gym, a space set up with sensory-specific equipment to provide a safe place for individuals with ASD to receive help. Many sensory gyms include weighted vests, supersized pillows, trampolines, ball pits, and more.
If you or someone you know has sensory processing disorders, including hyposensitivity, it’s recommended that you work with an occupational therapist. This is especially important for children who may have difficulty understanding and managing their sensory issues.
Living with Hyposensitivity
Many teenagers and adults will continue to use tools and techniques taught to them in occupational therapy to manage and live with their hyposensitivity. Behavioral therapy has also been known to help those with sensory disorders.
Some sensory disorders improve over time, as children age into adulthood. However, it doesn’t hurt to have some coping skills and ask for accommodations when possible. Also, avoiding stress is recommended, as stress can play a significant role in sensory processing difficulties, especially for adults.