The Intense World
I'm going to argue [...] that ASD involves, in fact, hyper-sensitivity to emotional states, both their own and others. This hypothesis is not new. In fact, Henry Markram, Tania Rinaldi, and Kamila Markram proposed exactly this in their 2007 paper titled, The Intense World Syndrome -- An Alternative Hypothesis for Autism. I would just like to underline their perspective here.
An analogy is useful for seeing why hyper- rather than hypo-sensitivity makes more sense. Imagine a person who is hypo-sensitive to sound. Is such a person more or less likely to walk into very loud environments? More likely! If you are less sensitive to sound you might actually prefer loud environments because that's how you get your acoustic sensation to a normal level. Conversely, a person who is hyper-sensitive to sound is going to avoid loud environments because it hurts.
Now consider the same scenario translated to the social/emotional domain. For starters let's agree that a large part of one's emotional stimulation comes from social situations. Not all emotional stimulation comes from the social domain, to be sure: I can get pretty emotional when I can't figure out how to fix my leaky faucet. But we get a lot more emotional and more often when a family member is sick or injured, or when a colleague rolls his or her eyes when we try to make a point, and so on. Now, imagine a person who is hyper-sensitive emotionally. Is such a person more or less likely to engage in social situations? Less! For someone who is hyper-sensitive to emotion, engaging in a normal social situation would be like walking into an excessively loud environment: it's uncomfortable and causes an avoidance response. ASD individuals may avoid social interaction not because they lack empathy but rather because social interaction is simply too stressful.
-- Greg Hickok
Quoted on Mon Dec 12th, 2011