Sensory issues are very common for people on the autism spectrum. Individuals vary in their responses to sensation -- some may be hypersensitive (over-sensitive) to some things, and hyposensitive (under-sensitive) to others. Any range and combination of the senses may be affected.
It's common for a child on the autism spectrum to have difficulty filtering out background sounds in order to focus on one particular voice.
Hypersensitive individuals will generally go to great lengths to avoid certain types of sensory stimulation. It is advisable for people with hypersensitivity problems to try and find items that will help them cope, and avoid having a sensory overload. Items like gloves, ear protection, certain fabrics, sunglasses, hoods, hats, etc. may work to cut down the stimulative effect of the environment they are in.
Hyperhearing: People with hyperhearing may wear ear protection for everyday sounds, cover or plug their ears, flinch, cringe, or even double over covering their ears because of certain sounds. They may become annoyed, irritated, or even feel ill because of sounds that others ignore or don't notice (the sound of chewing, the sound of breathing, the sound of food being digested, lights buzzing, etc). This can make it difficult to concentrate, and they may be misdiagnosed with ADD/ADHD. People with hyperhearing may also have difficulty sleeping, because for them, the world is never a quiet place.
They can benefit from earplugs, quiet environments, and white noise.
Hypertactility: Hypertactile indeviduals often resist being touched, hugged, or kissed. They are often unable to wear certain fabrics or types of clothes (jeans, tight shirts, bras, etc) due to discomfort. People with hypertactility may be picky eaters, as the textures of certain foods can be too much to handle. Hypertactile people may also have difficulty with wearing certain shoes, socks, using toothbrushes, brushes, combs, or other items with a high to medium sensory output. Women with hypertactality may also choose to keep their hair short, as their hair brushing against their skin can be irritating. Deep pressure and firm touch is usually less irritating for hypertactile indeviduals.
Hypervision: For people with hypervision, colors and lights can be overwhelming and even painful. They often have problems with sensory overload, and often choose to wear things like sunglasses that reduce glare, and hooded jackets or wide-brimmed hats which reduces/covers up their peripheral vision.
Hypertaste: People with hypertaste can be very picky eaters. Many flavors taste too strong or disgusting for them to eat, and they tend to be wary of trying new foods. They may never "grow out of" eating chicken nuggets and other "kid foods" which taste blander. Some people with hypertaste may spit out, feel nauseated, or even throw up because of the taste of certain foods.
Hypersmell: People with hypersmell are constantly bombarded with odors that others ignore or don't notice. Things like body odor, pet odor, fridge smells, certain smelly plastics, fumes, car exhaust, air fresheners, scented soaps and shampoos, etc. Simply walking within ten feet of a nail salon may cause a person with hypersmell to feel sick, or nauseous. Some people with hypersmell avoid cities due to the constant assault upon their noses. People with hypersmell may be 'neat freaks', showering frequently and trying to keep everything as clean and odorless as possible.
Vestibular Hypersensitivity: People with vestibular hypersensitivity are hypersensitive to movement. People with this hypersensitivity often get car sick and motion sick, and in more extreme cases, simple movements such as turning, pacing, or walking at a normal pace can cause problems for them.
Propioceptive Hypersensitivity: People with propioceptive hypersensitivity can feel things most other people cannot. This is not the same as hypertactility, as hypertactality is skin-deep. Propioceptive hypersensitivity goes deeper then skin. The person is constantly aware of what most every single joint, and what every single muscle is doing. And as the human body is constantly moving, it can feel rather disturbing and uncomfortable for some people. Certain positions and movements can be uncomfortable and bothersome, as well as physical activities and yoga. They may sit, stand, or walk in odd, or unusual ways that feel comfortable to only them.
Hyposensitivity is essentially the exact oposite of hypersensitivity - hyposensitive individuals are under-sensitive to certain types of sensory information. Hyposensitive people often go 'sensory seeking', where they try and seek out certain sensory inputs. Many people with hyposensitivity benefit from setting up a 'sensory diet' for themselves, which means a balanced roster of activities that adequately stimulate their senses.
Hypohearing - A person with hypohearing may not be able to hear things as easily, and filter out noises. This is distinct from damaged hearing (although people should be checked to make sure). People with hypohearing will seek out sounds. They are likely to love being surrounded by people chatting, and loud or continuous sounds like loud music, vacuum cleaners, drilling or sirens, and will often do things to make loud sounds. Children may bang objects or toys together, or shout very loudly. A person with hypohearing may not understand what people say to them at first, and they may need to have things repeated several times.
Hypotactality - Hypotactility means that a person's sense of touch is diminished and they will not be able to feel light touches or even pain and temperature extremes. A person with hypotactility may look for opportunities to experience “touch” by banging their head against the wall, biting themselves, playing roughly with other children or toys, hugging tightly and wearing tight and/or heavy clothes. They may also love having lots of blankets on their bed to provide deep pressure, and also love chewing or sucking on things. Parents and carers will need to be aware that such a child may hurt themselves, even breaking a bone, without noticing or recognizing the severity of their injury.
Hypovision - This is when a child’s vision can be affected to such an extent that they can only see outlines of objects. Symptoms and behaviour of this type of sensory problem include a child repeatedly moving their hands over objects, exploring everything in an unfamiliar place by touching it, repeatedly moving their hands and toys in front of their eyes, a love for bright lights, sunlight, bright colors and reflections, and an inability or difficulty to control their eye movements and to track moving objects.
Hypotaste - Hypotaste can mean that a child is always on the look-out for new things to put in their mouths and taste. Everything, no matter what is is, will be put in their mouths and they may suffer with excessive drooling and go around with their mouth open. They may also regurgitate food and whatever else they have eaten. People with hypotaste often like very strong tasting foods, like hot peppers.
Hyposmell - A child with this sensory problem will be drawn to smelly places, like the kitchen when you’re cooking or baking, and will constantly smell things - toys, grass, soil, plants, shoes, laundry…anything! They love interacting with smells and benefit from things like strongly scented soaps and shower gels.
Vestibular Hyposensitivity - This is when a child can swing, and rock themselves vigorously without feeling nauseated or dizzy. They will enjoy doing these types of movements and may have difficulty sitting still for long.
Proprioceptive hyposensitivity - This is quite a serious hyposensitivity problem because it means that a person has diminished awareness of where their body is in time and space, and so can fall over, bump into people, and drop things. They may be “floppy” and struggle to support themselves or hold onto things. A person with this problem may not be able to register hunger or the need to use the bathroom.