A Physical Hallmark for Autism: More Evidence of Loss of the Sense of Touch from Western Oregon University

December 15, 2015

To deepen our understanding of the difficulties with touch affecting children with ASD, we examined children's responses to touch on the face, hands and other areas. Touch is the sense that initiates social development in early life. It is touch on the face that stimulates the child to look at the face and listen to the voice of another person. And it is by engaging in face-to-face interaction that children first learn social and nonverbal communication skills.

We compared 199 preschool children with autism with 205 preschool children with typical development. Children with autism were distinguished by mixed pain and numbness on multiple areas of skin especially on the face, mouth and hands [1]. Signs of mixed pain and numbness within a general pattern not seeking or enjoying affectionate touch is seen with loss of small sensory fibers known as C tactile fibers [2,3]. These make up 75% of small sensory fibers in the skin of mammals, and are thought to mediate the affective and affiliative properties of touch [4].

We have previously hypothesized that autism is due to partial loss of the sense of touch [5]. In this study, we wanted to see whether we could screen for autism and discriminate autism severity based on physical signs of tactile impairment and failure to orient. The exercise correctly identified 91% of the children with autism on the basis of tactile impairment of the face and failure to orient, and correctly discriminated 81% of mild from severely autistic children on the basis of overall severity of tactile impairment [3]. The results suggest that signs of small fiber loss can be used as a physical hallmark of autism.

The diagnosis of small fiber loss is made on by skin biopsy with specialized neuronal staining. This fall we completed a biopsy study to confirm the presence of small fiber loss in children with autism. Results will be published early next year.


  1. L. Silva, M. Schalock, and K. Gabrielsen. "About face: Evaluating and managing tactile impairment at the time of autism diagnosis," Autism Research and Treatment, 2015.
  2. I. Morrison, L. Löken, J. Minde, J. Wessberg, I. Perini, I. Nennesmo, and H. Olausson, "Reduced C-afferent fibre density affects perceived pleasantness and empathy for touch," Brain, vol. 134, Part 4, pp. 1116-1126, 2011.
  3. G. Lauria, S. Hsieh, and O. Johansson. "European Federation of Neurological Societies/Peripheral Nerve Society Guideline on the use of skin biopsy in the diagnosis of small fiber neuropathy: Report of a joint task force of the European Federation of Neurological Societies and the Peripheral Nerve Society," European Journal of Neurology, vol. 17, pp. 903-912, e44-49, 2010.
  4. F. McGlone, J. Wessberg, and H. Olausson. "Discriminative and affective touch: Sensing and feeling,"Neuron, vol. 82, no. 4, pp. 737-755, 2014.
  5. L. Silva, R. Ayres, and M. Schalock. "A model and treatment for autism at the convergence of Chinese medicine and neuroscience: First 130 cases," Chinese Journal of Integrative Medicine, 17(6):421-429, 2011.