why do people with amnesia not forget their primary language?

Question

why do people with amnesia not forget their primary language?

In: 146

Answer 1

“Amnesia” can mean a lot of different things, as can memory. This is a pretty big rabbit hole.

First, there can be “anterograde” amnesia and “retrograde” amnesia. Anterograde means from a time forward, and retrograde means from a time backward. Let’s say a person had a neurological trauma back in April. If they developed Anterograde amnesia, they wouldn’t be able to form new memories after that point, and wouldn’t remember things from June, but could remember what they did in February. If they developed Retrograde amnesia, they could tell you what had happened in June, but might not remember February.

Next, amnesia isn’t necessarily complete. It’s not like a complete on- and off-switch on their memory.

Finally, there are different types of memory. For example, memory is sometimes categorized into what’s called “implicit” and “explicit” memory. Explicit memory is like knowing facts – e.g. the capital of Iowa – and implicit memory is like what people call “muscle memory” – e.g. shifting a manual transmission.

There was a very famous anterograde amnesia patient in the mid-20th century who everybody studies in undergraduate psychology classes who was a pianist. You could bring him a piece of music, and he would say he’d never seen it before. He would sight read it, and work on it a bit, getting better with practice. The next day, you could bring him the same piece, and he’d say he’d never seen it before. You could repeat this for two weeks, and on day 14, he’d say he’d never seen it before. But when he sat down to play it, he’d play it very fluently, like it had practiced it over a dozen times. When asked why he could play it so well, he’d rationalize that maybe the piece was just very easy.

This is a good demonstration of implicit and explicit memory. His memory of the title of the song or having played it yesterday is explicit memory, and his skills at playing the song are implicit memory; and his amnesia affected only one of the two types of memory.

In the case of language, it seems that sometimes language could be unaffected because the neurology that underlies the implicit memory of how to speak wasn’t damaged, even through the neurology that underlies forming new explicit memories was damaged.