a nerve 'impulse' [=a wave of electrical energy that is carried through the nerves to the brain]
Shopping with a credit card can lead to 'impulse buying'.
He had to resist the 'impulse' [='urge'] 'to shout'.
(..) It makes you weak. Why? How can you move faster than possible... fight longer than possible... without the most powerful impulse of the spirit? The fear of death. I do fear death. I fear dying in here... while my city burns. (..)2012 The Dark Knight Rises