I trialed for a month it as an off-label migraine preventative on recommendation from my neurologist.
Topamax can dampen neuronal activity in the language area of the brain for some people.
It was a terrifying experience, but it was also a valuable one as it changed the way I view intelligence.
About 10 days in, my writing and speech skills had devolved to that of a primary school aged child. I tried to type a text message and struggled to come up with simple words like “and”. My speech slowed down considerably.
The terrifying thing was that my internal world was still as complex and meaningful as it was before. All of the emotions I felt were real and legitimate. My cognition outside of language was intact, I could do math just fine and conceptualize and abstract problems.
In spite of this, I was unable to convey what I was feeling and thinking to the outside world. It felt like I was trapped inside my own body.
After recovering, my intuitive understanding of the link between language and intelligence was changed forever.
See the following for more info on Topamax/Topiramate language impairment: https://link.springer.com/article/10.1007/s10072-008-0906-5