Memory problems? Get a friend!

Transactive memory is a sort of brain trust where knowledge is split between two or more people. It allows people to have more information together than they do individually.

Transactive memory is a well-documented phenomenon among couples, co-workers and between friends. 

Our friends can be much-needed backups for our own memories, helping us to navigate the world in general, as well as recall our own specific histories.

It is something we know intuitively, but now research has confirmed it: the closer the friendship, the more interconnected the memories. Same-gender friendships were more likely to have integrated networks, while mixed-gender pairs tended to be more differentiated. Still, the type of memory sharing did not have an influence on friendship quality; what mattered was the fact that it existed at all.

Transactive memory — more than how much time people spent together, more even than how long they had been friends — was the factor most closely linked to the strength of the friendship.

The stronger your system is, the more satisfied you are with your friendship because you can gain more benefits from it. It also might lead to more commitment, because it makes you more interested in maintaining that friendship.

The researchers focused their study on networks of semantic memory (general knowledge) rather than episodic (autobiographical) memory though both types are likely present between best friends.

Friendships are at their best when you can rely on friends to help you understand both the past and the present, to keep track of where you have been and make sense of what you are doing.

A good friend is like an extension of our own mind.