Those articles frame the issue from a neurobiological standpoint. However, a key point is that science understands these issues very little right now. I have had some doctors suggest that I consider that it could have a psychological origin (eg. trauma, PTSD, or many other things), so I am exploring both possibilities right now (neurobiological and psychological).
The best academic summary I've found is an 2012 policy statement by the American Academy of Pediatrics:
"Occupational therapy with the use of sensory-based therapies may be acceptable as one of the components of a comprehensive treatment plan. However, parents should be informed that the amount of research regarding the effectiveness of sensory integration therapy is limited and inconclusive."
So I'm moving forward slowly, aware that science doesn't understand it very well yet. But it's a persistent problem that causes distress many times a day, so it's something that I really have to address.
I have fairly strong problems with touch defensiveness and sound defensiveness. (certain touch or sound sensations will cause me to pull away from them, when most people could tolerate those sensations). I have mild sensitivity to light, but it's not as severe, and it doesn't cause nearly as much distress in normal daily life as the sound and touch do.