Every one of your organs is vibrating in a different frequency. There are reports about how there were torture techniques during world wars with resonant frequencies. Just think about how sound alone at just the right pitch is capable of causing a wine glass to shatter. As for the things becoming hotter with faster vibration, that is true and it has a lot to do with kinetic energy and friction. When we heat up our food and cook it, we are causing the water molecules in it to move faster and faster. Your brain does have a certain frequency and it can be measured, there have been studies and researches about brainwaves in different sleep phases and during different activities. Your brain will transmit a different frequency when you are solving a puzzle, reading, sleeping or meditating. There have been some attempts of research on monks where they put an ice cold blanket over them while they were meditating and the blanket became hot faster than in situations where they would put it on people not meditating and heating it with their normal body heat. This, of course, is a topic that still lacks the empirical evidence and has the potential for additional research since it is still very vague and not confirmed. When we stop using science for military purposes, maybe these kind of things will finally have their little moment in the scientific Sun :)