Too much sensory overload may result in systems shutdowns, when the person loses some or all of the normal functioning.

Shutdown may feel different to different people, but it is very unpleasant and often frightening. If the sensory stimulation is overwhelming autistic people can shut their systems off. To avoid painful sounds they shut down hearing. (Though certain frequencies cannot be shut down.) Continuous noises (fans, microwave, heating) that do not bother other people may be very annoying. To shut down the painful channel they may engage in stereotypic behaviours, or deliberately distract themselves through other channels (for example, touching objects when hearing is overwhelming) or withdraw altogether.

Autistic children learn very early in life to control their environment, and the amount of information coming in. Many autistic children are suspected to be deaf, as they sometimes do not react to sounds. A typical situation: you call your child’s name (who’s in the same room) and…no reaction whatsoever as if the boy were deaf. His hearing, however, is often even more acute than average, but the child learns to ‘switch it off’ when he experiences information overload.

When sensory input becomes too intense (and often painful) a child learns to shut off his sensory channels and withdraw into his own world. Temple Grandin (2006) hypothesizes that by doing this the autistic child creates his or her own self-imposed sensory deprivation that leads to secondary central nervous system abnormalities that happen as a result of the autistic child’s avoidance of input. She recounts that auditory and tactile input often overwhelmed her, and loud noise hurt her ears. When noise and sensory stimulation became too intense, she was able to shut off her hearing and retreat into her own world.

Temple Grandin suggests that the possibility of secondary damage of the nervous system may explain why young children receiving early intervention have a better prognosis than children who do not receive special treatment do. If not addressed early in life these problems may lead to irreversible hindrance of development. The timing of the sensory problems can often explain the different routes of their cognitive, linguistic, communication, social and emotional development.

Bob Morris (1999) argues that attempted use of different sensory perceptual mechanisms by a baby (who would be diagnosed autistic), without any help from a perceptive carer to sort out and deal with these differences (both problems and abilities) may aggravate the condition. The earlier the carer understands the differences and accommodates the person (via the adjustment of the environment and appropriate intervention), the more likely the individual will become a fully functional, but significantly different (in talents and thinking).

If there is no appropriate support they may stay withdrawn from the outside world well into adulthood, unwilling and with time unable to leave the ‘sanctuary’ of autism. Their world becomes what Donna Williams calls ‘simply be’ – the world without words, but rich in experience of sounds, patterns, colours and textures.

When sensory input becomes too intense and often painful, shutting off the sensory channels helps the child withdraw into his/her own world.

Donna Williams (1996) subdivides shutdowns into temporary partial and extended systems shutdowns. Temporary systems shutdowns work by shutting down the ability to process information on a number of channels so that information can be efficiently processed on whatever channel or channels are remaining. Temporary systems shutdowns can affect the processing of body awareness, touch, taste, smell, vision or hearing. They can be partial or almost total for any one sense. Partial shutdown means that only a part of processing may fall out of a particular sense (partial meaning deafness, partial meaning blindness, partial touch deadness, etc.). For example, a high-functioning person with autism could work with overload and shutdown in a way that never left him with any one system shutdown permanently but his systems in a constant state of shift. Total shutdowns mean that though, for instance, eyes continue to see and ears to hear, the brain does not process any meaning of what is being seen or heard – resulting in temporary sensory agnosia.

Thus, systems shutdowns may be considered as an involuntary adaptation (compensation) when the brain shuts certain systems off to improve the level of functioning in others (Williams 1996).


Grandin, T. (2006) Thinking in Pictures, 2nd edn. London: Bloomsbury.

Morris, B. (1999) ‘New light and insight on an old matter.’ Autism99 Internet Conference Paper.

Williams, D. (1996) Autism: an Inside-Out Approach. London: Jessica Kingsley Publishers.

Written by Olga Bogdashina on behalf of Integrated Treatment Services