An autistic lady named Temple Grandin had a device built for herself that she referred to as her “Squeeze-Box.” She tells the story of visiting her aunt's ranch in Arizona where she saw cattle being confined in a squeeze chute while they were inoculated. The cattle appeared to relax and calm down under that strong, full-body pressure. Young Temple Grandin wished she had a squeeze box of her own to help her deal with the hyper-sensory issues which are common in autism.
I first heard this story from a cattleman who had also observed this natural reaction in his own herd of cows. I found the information most interesting because I had already utilized the idea of hugging-while-teaching my own small children who are not autistic. I believe it is natural for the senses to relax and focus when the physical body is held safely and comfortingly.