roll for initiative

Reading (and writing) about the Curse of Knowledge yesterday got me thinking about source amnesia.

In another life, a long long time ago, I was working on a Ph.D. in cognitive psychology, studying memory and the fallibility thereof. One concept I researched was source amnesia.

Source amnesia describes the phenomenon of when you forget when or where you learned something while still retaining the factual knowledge. In essence, you forget the source of your knowledge but you retain the actual fact.

Source amnesia is different from retrograde amnesia where you forget your biographical knowledge - the classic TV type of amnesia. It’s also different from anterograde amnesia, where you retain everything you know up to a point but are unable to learn or retain anything new - like HM, the classic anterograde amnesiac.

To understand source amnesia, I think it’s helpful to break memory down into various sub-components. One way to slice it is to differentiate between declarative memory and procedural memory. Declarative memory is knowledge of facts and events, while procedural memory is knowledge of how to do stuff.

Declarative memory can be further divided into two sub-categories - “what” memory (i.e., “semantic memory” or knowledge of facts) and “when” memory (i.e., “episodic memory” or knowledge of specific events or moments in time that you have experienced).

Back to source amnesia … when you learn something new it becomes part of your declarative memory. Specifically, it becomes part of your semantic memory. For some reason, information about the specific episode that resulted in you learning something new is rarely encoded in episodic memory. As a result, you retain the new fact you just learned in semantic memory, but you don’t store the associated event-related information in episodic memory … and voilà - source amnesia.

For example, you know that Ottawa is the capital of Canada (you did know that right?). That’s part of your semantic memory. But I’m guessing that you can’t remember when you learned that (unless you JUST learned that in the last … say … 2 dozen or so words). Remembering the when requires that you encode the specifics of the moment you learned that Ottawa is the capital of Canada - but because you didn’t, you have source amnesia.

I do have to take some exception to the wikipedia article on source amnesia. In that article, they refer to source amnesia as an “explicit memory disorder”. Granted, I haven’t been in grad school for many moons so I’m not (and probably never was) up on the latest on source amnesia, but I’d be hesitant to describe source amnesia as a “disorder”. It’s way too common to be a disorder - it’s almost a natural byproduct of the differences between semantic memory and episodic memory.

And now to bring it full circle with the Curse of Knowledge …

The reason I started thinking about this source amnesia thing in the first place was because it strikes me that the curse of knowledge is somehow related to source amnesia…. Maybe source amnesia falls into a curse of knowledge subset … or maybe it’s the other way around … maybe the curse of knowledge is a symptom or a byproduct of source amnesia.

If you don’t encode the episodic information related to new knowledge it would seem as if you always possessed said knowledge … which would make it hard for you to think back to a time when you didn’t know what you now know (uh oh … I’m getting Rumsfeldian again) and that might make it difficult to sympathize with those who don’t know what you now know.

Hmmm that seems like a bit of a stretch to me. I’ll have to modern jackass that one some more.