Many instructors suggest using emotion, or 'emotional content' to activate your responsiveness, basic power, and courage, etc. The primary emotion which is usually imagined for this is anger or possibly fear.
This advice and approach is a little off course and introduces personality issues where they are best kept quiet. Instead...
...What you need to find is wildness. Be wilder than your adversary! This does NOT mean crazy or jumpy or loud and offensive. It means like a wild animal, with appropriate calmness and attention - on the edge of fineness of attention and sudden responsiveness. Emotional responses like anger (and fear, etc) have too much personal investment. You've got to be able to just let the animal take over. Animal is not an emotional response, it's far more tuned in to the moment - use it!
The other benefits are that the animal has better judgement than the angry person, and much better perception. Indeed, it has a sense of humour, too.
You'll find that the animal is far less belligerant than the emotionally strung out, or hyped up "warrior". Its amiable nature is an asset in confrontation - and also, it can fight much better - when necessary.
Don't trust me on this. Try it. Mail me if you have an opinion.