It is often said that people with autism suffer for sensory problems called “hypersensitivity”: the sensory awareness is too acute, and the taste, smell, touch, hearing, vision, etc. becomes heightened and often overwhelming, or sometimes fascinating. Have a look at this page, for example:
In the books by Donna Williams or Temple Grandin who reported their own experience of autism, we can find vivid descriptions of hypersensitivity.
“When left alone, I would often space out and become hypnotized. I could sit for hours on the beach watching sand dribbling through my fingers. I’d study each individual grain of sand as it flowed between my fingers. Each grain was different, and I was like a scientist studying the grains under a microscope. As I scrutinized their shapes and contours, I went into a trance which cut me off from the sights and sounds around me.”[Grandin, T. (2006). Thinking in pictures. New York: Bloomsbury, p. 34]
“I learned eventually to lose myself in anything I desired – the patterns on the wallpaper or the carpet, the sound of something over and over again, the repetitive hollow sound I’d get from tapping my chin. Even people become no problem. Their words became a mumbling jumble, their voices a pattern of sounds. I could look through them until I wasn’t there, and then, later, felt that I had lost myself in them.”[Williams, D. (1992). Nobody nowhere. London: Jessica Kingsley Publishers, p. 11]
It seems that the unity of sensations in object perception is dismantled and one specific sensation becomes heightened (tactile sensation of the sand, visual pattern of the wallpaper, sound pattern of the voice, etc.). In line with this, it also seems that the object perception loses its ordinary meaning. Sands are just “shapes and contours” to look at, the wallpaper is mere visual “patterns”, and human voices are no more than “a pattern of sounds”.
Hypersensitivity is very curious because it happens as if the perception is dissociated into “pure sensation”, which is not supposed to exist in phenomenology of perception. We always already perceive something as “something” (i.e., a certain object), and nothing appears as mere sense data such as color-data, tone-date, pressure, warmth and so on (e.g., Merleau-Ponty, 1945).
However, one specific sensation of the object becomes heightened in hypersensitivity, and the perceived object seems to lose its meaning as “something”. Furthermore, the perceiving subject is somehow “hypnotized” or “lost” in sensation. There is no ordinary distinction between the perceiving subject and the perceived object. As the title of Williams’ book indicates, there is nobody who perceives, neither the perceived object. Only the undifferentiated sensation seems to be left in the middle of nowhere.