Bad Memory?

I remember vividly that when i was in form 5, my mom made me take gingko and salmon fish oil everyday just because i told her i have bad memory. it was true, up to a certain extend.

When it comes to subjects that require reading and remembering like history or biology or moral, i just cant seem to remember anything but only some touch n go points here and there. my memory power was really bad and mom worried that i'd fail these subjects if the reason for the failure was my memory

oh well, if memory power was really that bad, i believe by right i wouldn't even remember those 'steps' of formulae applications for additional mathematics, like how to get those figures or if more, the long and complicated chemical equations? or the structural formula of each chemical molecule? or the principle behind each physical reaction by the molecular forces or whatnot.

my question is, is memory something subtle? if we cant seem to remember an occasion or something, should we blame on the memory power or the subject to it? like, the subject is not of any importance or significance?

i personally believe its the latter. its not so much on we're-borned-with-bad-memory but its the subject that matters. if its all about something (or someone) we love, we care or something (or someone) dear to us, we tend to remember every single detail bout them. but if its otherwise and insignificant in our life, we'd just choose float by and be ignorant.

well after all we've only limited space in our cerebral, haven't we?