TThe Critical Difference Between Declarative and Procedural Memoryhe following is an excerpt from Master Japanese: The Beginner’s Step-by-Step Guide to Learning Nihongo the Fun Way.

Most learners mistake “studying” a language for actually “acquiring” a language. The two are very different beasts, which is one of the major reasons why most adult language learners fail despite years of effort: they spend all their time reading about Japanese instead of spending the requisite time in Japanese. This is like trying to learn how to drive by reading the car’s owner’s manual. Obviously not a good recipe for success.

Or here is a metaphor using soccer if that hits closer to home:

“Imagine me teaching you soccer through books. I insist you memorize the physics of each possible shot, over 1–2 years, before we get on the field. How will you do? Well, first, you’ll likely quit before you ever touch a ball. Second, when you get on the field, you’ll have to start from scratch, turning that paper knowledge into practical knowledge.” ―Tim Ferriss, The 4-Hour Chef

I am not saying that language study is inherently bad or that book learning should be completely avoided, but it is important to understand its limitations and ensure that you get the real-world, human to human interaction your brain needs to internalize a language and reach conversational fluency.

One of the key differences between language “study” and language “acquisition” is the type of memory developed in each:

  • Language study (especially formal, classroom-based learning) tends to create and reinforce “declarative memory”.
  • Language acquisition (which only happens when you get sufficient input and active practice) forms and strengthens “procedural memory”.

Dr. Victor Ferreira, a psychologist at the University of California, San Diego, has done some fascinating studies on procedural memory’s role in language, concluding that:

“…the core knowledge underlying human syntactic ability—one of the most creative capacities known in nature, and one that is commonly thought to depend on advanced and flexible intelligent functioning—is shaped by a specialized system of basic memory mechanisms that are themselves found in even the simplest of organisms.”

Declarative memories have the following attributes:

  • They are conscious.
  • You can put them into words.
  • They store explicit information (i.e. knowing that something is the case).

For example:

  • Knowing that your bike is 6061-T6 aluminum.
  • Knowing that Japanese is a Subject-Object-Verb language.

Procedural memories, on the other hand:

  • Are unconscious.
  • Cannot be put into words as easily, if at all.
  • Store implicit information (i.e. knowing how to do something).

For example:

  • Knowing how to ride your bike.
  • Properly speaking in SOV order without thinking.

It’s important to note that both kinds of memory are involved in language acquisition, but most academic approaches focus almost entirely on declarative memory tasks, all but ignoring the activities required to build procedural memories. This is why you can emerge from ten years of formal language study unable to have even the most basic conversation with native speakers. Sure, you can rattle off a list of vocabulary words, but you can’t use the same words in context or understand them when spoken back to you because you have only worked out your declarative memory muscles. Your weak, flabby procedural muscles simply can’t keep up with the rapid-fire pace of natural speech.