I am dyslexic and bi-polar and this was not discovered until i was well past youth and school exams that would fill me with utter fear. I learned from a kindly gent years later at exams:
On the word go pick up the paper and read it through. Pencil mark the ones that you have instant recall on until you have read the whole paper over.
The answer those 'easy ones' making sure you clearly number them. By the time you have done these you will have ploughed through alot of the paper. AND, you will have calmed down quite a bit.
Look at the other questions and be surprised what you will now recall.
The questions that you have a blank on--leave.
Do the others come back to that real stinker last and write out just what you do know.
Dear Lord i wish i had known this method all those years ago. Please let me/us know how you go.