You can donate your organs, if you die of a head injury. You cannot donate tissues like bone, skin, or corneas, because those are considered “life enhancing.” Donated tissue has a similar restriction to donated blood, so you’re right about that bit.

Organs like the kidneys, liver, heart, lung, pancreas, and stomach are “life saving” and don’t have any restrictions. When you die, you’ll be evaluated for any potential donation, and if you are a candidate for donating organs, someone will come talk to your family about it. Talk to your family about what you would want.