Sensory issues

Sensory issues are so commonly reported by people on the autism spectrum that certain authors have suggested that sensory disturbances are a primary deficit, rather than a secondary feature. Individuals may be hypersensitive (over-sensitive) or hyposensitive (under-sensitive). Any of the senses can be affected.

Tremendous variations exist between people; an individual can show a mixed profile of hypersensitivity in certain areas, contrasting with hyposensitivity in others.

Hypersensitivity

Hypersensitivity explains the child who clamps his hands over his ears every time the phone rings, or who refuses to eat certain textures of food.

Hyposensitivity

Hyposensitivity is displayed in the child oblivious to temperature, or with a high pain threshold. This should not be confused with cases where a serious illness or injury goes undetected due to the child's inability to communicate his discomfort. Abnormal responses to pain are also noted by some parents: a child who bangs her head repeatedly against the wall may giggle rather than cry. Some children do engage in self-injurious behaviors (e.g. eye-poking, hand-biting) but seem oblivious to any pain.

In sharp contrast the same child may find hair washing and brushing unbearable and certain textures and materials against the skin insufferable. The child may shy away from gentle maternal embraces but scream with delight during rough-and-tumble play.

Sounds

Difficulty filtering out unnecessary sounds is a common problem. The listener may find it hard to attend to noteworthy details (e.g. listening to a speaker's voice when there is background noise). Conversely, one feature in the environment may be focused on, to the exclusion of all else.