A state where the mind is processing too much information, thus sending the host's mind into a place where they think everything is wrong with themselves. Mental Pain also has the chance to tighten the muscles around the body if the emotions become potent, sending the host also in a state of panic, for they might think something is constricting them.
"No matter how hard you try, he won't be fine for a bit. He's in a state of Mental Despair"