Iambic, sure, but it’s not, in itself, pentameter.
WOOSH. 
I think “jamais vu” is perhaps closest:
Ed
I once convinced myself I had only imagined there was such a word as ‘bread’ by repeating it over and over. Some sort of repeated stimulus fatigue, I guess - maybe like when you’re in a room with a bad smell, you don’t notice it after a while.
For me, it often happens with the simplest words, like “milk” or “work”.
Thank the OP for this thread, very reassuring it is.
I used to work in a place where once in a while I would have to write “Office of Admissions” on 300+ lunch tickets. Even though I did all of these in a row, it’s amazing how so many people got ones with admissions spelled wrong. It was like my brain would stop halfway through writing it and go “What IS that word?!”
A few years ago, I was reading a book and saw the word “blood.” I read it with a long ‘o’ or like 'blewd." I kept thinking, “Blewd. Blewd. What the hell is that word?”
Odd that.
This happens to me all the time when I’m grading kids’ papers, especially after the fortieth one or so, then someone misspells a word and I can’t remember how you really do spell the word for a minute.
Warmth. Warmth warmth warmth. After I stare at it for a moment, the word dissolves into individual letters that have no relation to one another.
My least favorite word effect is when I routinely misspell a word, then pause and correct it, but do this so consistently that I’ve seen the correct and incorrect spellings almost as often. It wreaks havoc with my ‘feel’ for the word.
Warmth warmth warmth.
I’ve had this happen to me. Most recently on the word “orchestral”. I knew it was spelled right, but my brain said it was worng, even after I looked it up.
Yeah, I had that same reaction. It was one of those weird/cool things that happened to me a lot as a kid, though it hasn’t happened lately.
Badger badger badger badger badger.
To the OP: yes, this happens to me a lot. I also get words stuck in my head that keep popping up out of nowhere for a day or two. For some reason, today’s word is edentulous.
I remember this happening to me in the sixth grade with the word ‘quart’. Since then I’ve had complex and grand mal siezures, all sorts of odd brain feelings. I think that was the start of it.
This happens to me all the time when I’m scoring my Feud games. Today one answer was Reykjavik - it was spelled eighteen different ways! I have to correct them all.
God, I hope I spelled that right.
Are you sure it was spelled eighteen different ways? 
I have had the effect of the OP and once years ago I had the opposite. I was a writing something and wrote something like, “I am shore we will have a good time.” I then realised that shore was not the spelling for the homophone that I intended. I must have wracked my brain for 5 minutes but could not come up with an alternate spelling or even a way to look it up, like it had to begin sh.
I gave up and wrote “I am certain…” A minute later sure popped into my head. It was a very humbling experience.
Click on the PDF link that goes with that youtube video and I guarantee that any sane person will suffer semantic saturation of the word “chicken.”
Have I missed a joke here or is that how you say “saturation”?
I thought he was saying semantic satiation?
That happened to me just tonight with the word, “blessing.”
Blessing, blessing, blessing.
I honestly can’t tell if I made that word up.