For an MRI of the head, you lie with your head inside a special machine (scanner) that has a strong magnet. The MRI can show tissue damage or disease, such as infection or inflammation, or a tumor, stroke, or seizure. Information from an MRI can be saved and stored on a computer for more study.
what has been seen cannot be unseen. The act of witnessing something so traumatic or disturbing that it is futilely wished to be unseen. Most commonly experienced on 4chan's /b/ or senior citizen dating websites. Me: Oh hey, look, some Nigerian dude emailed me a file called BlueGoatseWaffles! Maybe its a picture of blue goats doing people stuff...like cooking waffles! Me: What has been seen cannot be unseen.
While most of us are limited to the visible spectrum, people with a condition called aphakia possess ultraviolet vision. Aphakia is the lack of a lens, due to surgical removal for cataracts or congenital defects. The lens normally blocks ultraviolet light, so without it, people are able to see beyond the visible spectrum and perceive wavelengths up to about 300 nanometres as having a blue-white colour. A study in 2014 pointed out that, in a manner of speaking, we all can see infrared photons, too.