In a book called 'diet, delinquency and crime' the author talks about metal from fish and how they affect the pesonality. However the author never mentioned mercury fillings, maybe because the book is very old and they didnt know about it then.

basically one of the articles in the book was of a boy who ate fish from his local sea and became inccreasingly aggressive over the years, and when tested they found he had high levels of metals in his blood etc.