It's a very good question. On the one hand, it is certainly something which can explain things well, on the other hand, my feeling is that sometimes the reaction may be a bit of eye-rolling. I do like however your story about how things changed once you discovered (I assume you mean you began to take medication or perhaps taking some other action), and I think that if you weave that narrative, it may be a good idea to go ahead and write that. Just be wary of "making excuses" and even if you DO have a good reason, it's always a good idea to be courageous and take the blame fully upon your shoulders. (As well as proving your amazing potential for intellectual and academic success through other ways)
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