Can my brain become too full?

Answered by Professor Ian McLaren, University of Exeter

You asked if the brain overwrites old information each time I learn something new. The answer is when you learn new things you do forget the older stuff to some extent but it's not as bad as it sounds. Say you learn a list of metals and flower names. Then afterwards you learn a list of trees and plants. Learning that second list will make your memory for the first worse. We don't think it overwrites it. If I now tell you that that first list was metals and flower names and you use those cues, things you'd apparently forgotten resurface. It seems like they were harder to retrieve and we think that inaccessibility protects them, actually from being overwritten. If you didn't protect it in that way it would get overwritten and you really would lose stuff. The other question was, 'Is all this learning good for me or should I concentrate on learning less?' The problem as we age with our memories seems to be not a lack of capacity but we get worse at using it. We're not as good at controlling it. If you keep on learning things and using your memory a great deal, that can only help. It's a use-it-or-lose-it kind of idea. Hope that helps!