Sensory Integration Disorder (or Sensory Processing Disorder) is a fancy way to label kids who have MUCH more than the "usual" difficulty with sights, sounds and the way things feel. Emperor is actually the OPPOSITE of the little boy in the video. He needs much more sensory input to make sense of the world around him. Instead of shaking your hand, he might bump into you and get into your face and act silly. It's not an excuse, and we're working on it, but it is a reason he acts much differently. Unlike in the video, he enjoys lots of touch to the point where other people feel attacked. Some people liken SPD to autism, or think of it as a "red flag."
When he was a toddler, his ABA therapist taught me things that help him feel better like jumping on a mini-trampoline, being thrown onto a couch, or wrapped in a blanket and pummelled in play. These things give his "vestibular system," (the body system that tells you that you are sitting up and, say, holding your pencil too hard) the input he needs. This leads to working with my children like cannibals and missionaries: Emperor needs a LOT of input and my autistic kids just hate when people get too close or are too loud, etc. We have a lot of fights about Emperor being annoying. Emperor doesn't get into the appropriate amount of trouble because THEY would never do that... but Emperor would argue that G doesn't get into enough trouble for his yelling. Sigh. Every now and then, we all get along, though.