In our previous blog, we addressed how the sensory systems work in an average person.  However, the senses don’t always operate so smoothly in everyone.

ASD and the Senses

Sensory differences are a key component of Autism Spectrum Disorder.  Each person with autism has their own unique sensory challenges.  Some experience hypersensitivity, meaning they require very little sensory input.  These individuals can experience overstimulation with small to moderate amounts of input. Others experience hyposensitivity, needing a greater amount of information from their senses.

Remember: The same person with Autism or Asperger’s Syndrome may experience hypersensitivity with one sense and also hyposensitivity with another.

Behavior and Sensory Sensitivity

Sensory sensitivity may cause an autistic person to struggle with everyday sensory information. This sensitivity can result in stress, anxiety, and possibly physical pain. Withdrawal, meltdown, and various unexpected behaviors are the outward expressions of experiencing sensory overload.

What Hypersensitivity and Hyposensitivity look and feel like in someone with Autism

Hypersensitive vs HyposensitiveSensory Challenges - Hypersensitive vs HyposensitiveVision (sight)

HYPER (OVER) SENSITIVE

  • Vision may be distorted
    • objects and bright lights can appear to jump around.
    • Fragmentation or pixilation of images.
  • Focusing on a single detail may be easier than looking at the whole object.
  • Sensitivity to light may result in difficulties getting a good night’s sleep.

HYPO (UNDER) SENSITIVE

  • Objects can lose some of their features or appear as shadows.
  • Issues with central and peripheral vision
  • Central vision blurs while peripheral vision remains sharp.
    or
  • Central objects are magnified while peripheral vision blurs.
  • Poor depth perception, resulting in problems with throwing and catching, as well as general clumsiness.

Audition (hearing)

HYPER (OVER) SENSITIVE

  • Noise might be magnified resulting in the distortion and muddling of sounds.
  • Conversations in the distance may be crystal clear.
  • Difficulty concentrating due to an inability to filter out background noise

HYPO (UNDER) SENSITIVE

  • Only one ear may receive sounds clearly.
  • Particular sounds may be completely inaudible.
  • Crowds and noise may be pleasurable
  • May bang doors and objects, especially in quiet environments.

Olfaction (smell)

HYPER (OVER) SENSITIVE

  • Toileting problems can be the result of perceiving smells as intense and overpowering.
  • May avoid or actively refuse to go near people that wear perfume, and scented shampoos, lotions, etc.

HYPO (UNDER) SENSITIVE

  • Failure to notice strong odors, including their own body odor.
  • Licking things to determine what they are.

Gustation (taste)

HYPER (OVER) SENSITIVE

  • Restricts diet because:
  • Some flavors overpower the flavor of foods – therefore they limit themselves to bland foods
  • Textures may cause discomfort – resulting in the selection of only smooth foods e.g. mashed potatoes or ice-cream.

HYPO (UNDER) SENSITIVE

  • Prefers very spicy or strong-tasting food.
  • May exhibit “pica,” eating or mouthing non-edible items

Somatosensation (touch)

HYPER (OVER) SENSITIVE

  • May not like to be touched due to the pain and discomfort associated with it. Close relationships are difficult to maintain without touch.
  • Will avoid wearing anything on hands or feet.
  • Grooming, specifically brushing and washing hair is difficult and possibly avoided.
  • Type of clothing and textures is important when choosing what to wear. May have a limited wardrobe.

HYPO (UNDER) SENSITIVE

  • Holds others tightly, possibly resulting in discomfort for the one being squeezed
  • May not register pain until it becomes extreme.
  • May choke, due to a lack of awareness of food in the mouth.
  • Possibility of self-harm
  • Weighted blankets and other heavy items are enjoyable.
  • Chews on clothing, especially the collar and sleeves, as well as other inedible objects.

Balance (vestibular)

HYPER (OVER) SENSITIVE

  • Difficulties in controlling body movements.
  • Stopping quickly is difficult.
  • Experiences motion sickness
  • Prefers to remain upright with feet on the ground.

HYPO (UNDER) SENSITIVE

  • Enjoys rocking, swinging and/or spinning.

Body awareness (proprioception)

HYPER (OVER) SENSITIVE

  • Fine motor skills may be difficult.
  • Turns the entire body rather than just the head to look at something.

HYPO (UNDER) SENSITIVE

  • Personal space invader.
  • Difficulty navigating rooms and avoiding obstructions.
  • Bumps into people and objects.
  • May touch the wall while walking down a hallway

Interoception (the internal sense)

HYPER (OVER) SENSITIVE

  • May be able to hear blood rushing through veins.
  • May complain of noise when the room is quiet.

HYPO (UNDER) SENSITIVE

  • May be unaware of hunger, nausea, body temperature, until the person with ASD is shaking, vomiting, or has heat exhaustion

In addition to the areas listed above some people with autism experience a rare condition known as Synesthesia. People with this condition receive information through one sense yet another sense interprets it. For example, they may hear colors or smell sounds.

All of these sensory challenges affect behavior. The affected behaviors influence an individual’s relationships with others as well as the quality of their life. In the next blog, we’ll discuss strategies for dealing with these hypo and hypersensitivities.

Rebecca J. Weaver is a Certified Autism Specialist at Independent with Autism, working to empower individuals with ASD. Need help creating positive strategies? Check out IndependentwithAutism.com for more information.