People with Autism Spectrum Disorder (ASD) typically have difficulty processing sensory information such as sounds, sights, and smells. This is usually referred to as having issues with “sensory integration”, or having sensory sensitivity, and is caused by differences in how the brain of a person with ASD understands and prioritizes the sensory information picked up by the body’s many sensory receptors. When this breakdown in communication becomes too intense, the person with ASD may become overwhelmed, anxious, or even feel physical pain. When this occurs, some with ASD may act out.

The over and under-sensitivity ASD people experience may affect some or all of the following seven senses:

Sight

Including seeing objects as darker than they really are, blurred central vision, having poor depth perception (resulting in clumsiness), and distorted or fragmented images.

Sound

Imbalanced hearing (hearing sounds only in one ear), may either enjoy loud noises or be very agitated by them, may have difficulty cutting out background noise (affecting concentration), sounds may be distorted. These difficulties may also contribute to balance issues.

Touch

A person with ASD may either crave touch (and not know how much to apply, such as holding a person too tightly) and have a high pain threshold, or shun touch (even common gestures of affection, such as hugs) and struggle with certain sensations, such as those produced by rough fabrics, hair brushing, etc.

Taste

Some with ASD may crave strong tasting foods (such as very spicy foods) or even go so far as to try to eat non-edible substances like Play Dough, while those who are hypersensitive to taste will shun all but the blandest foods, and may dislike foods with anything but a smooth texture.

Smell

Some people with ASD may have no sense of smell and remain unaware of strong odours (leading them to rely on oral cues; they may taste things to get a better sense of them), while others may find common smells (such as from deodorants, lotions, shampoos, and perfumes) too strong to bear. For this reason, they may be extremely averse to going to the bathroom.

Balance (‘vestibular’)

People with ASD may rock back and forth so as to get enough input on where they are situated, as they lack a sense of balance. They may have difficulties with sports, particularly anything gymnastic where the head is removed from an upright position. They may be more prone to car sickness than those who lack ASD.

Body awareness (‘proprioception’)

As people with ASD struggle to orient their bodies properly in space, they may stand too close to others, have a hard time navigating rooms or moving around obstructions (including people), experience difficulties with fine motor skills, or experience Synaesthesia (a condition where senses are “confused”, i.e. one will hear or taste a colour).