I have a high needs 8 year old. I find there are certain things that always trigger her -- poor sleep, hunger, watching TV/playing video games, too much play with other people. It takes a lot of discipline to keep these in balance, but the effort pays off most of the time.
As far as discipline goes, every child has different needs and every parent has their own style. Most likely there is an underlying cause to the behavior -- be it developmental, physical, emotion -- and as parents we rarely know the true cause.
"Time in" rather than "Time out," reading together, going outside in nature can all be healing.
Hand in Hand Parenting has some good gentle discipline resources. "Raising Your Spirited Child" or "The Highly Sensitive Child" may be good resource to assess your son's temperament.
The "Your X-Year Old" series of books is often a good measuring stick to figure out age expected behaviors.
Time ins, punishment, rewards, etc are all linked to short term wins -- not long term success. "Unconditional Parenting" is one of my favorite books on the subject.
Finally, if this is a new behavior, it is possible there was an outside catalyst -- not what a parent wants to think about. Do work on giving your son tools to communicate -- words, drawings, a good understanding of his biology (age appropriate). Having a neutral professional he can talk to is helpful as well.
Good luck -- what a lucky son to have a father so humble as to ask for help.