Well, the story goes like this: In a sci-fi space war setting, the protagonist is blasted away and somehow he crashes in a medieval-setting planet. Over there he is rescued by the princess of a warring kingdom. The protagonist's faction use a gauntlet connected to the neural system that can perform a variety of tasks, and for a handwave-y reason for now, he uses parts of his ship to build one gauntlet for the princess. And for better explanation the state of his society and why he's at war, he transfers his "general culture" knowledge via the gauntlet to her. Since she's on a society where the war norm are horses, knights, swords, bows and catapults (with a spice of magic), suddenly knowing about space stuff would leave her quite shocked, and then won't understand or even remember at first glance, but suddenly she would think in mixed terms of her and his knowledge, and even when speaking she would slip some futuristic nonsense without realizing.
So, is there any health risks involved in getting sudden knowledge? Is it safe to "implant" this knowledge quickly, or does it have to be slowly to cause no harm?