In the 1960's, a neuroscientist named Paul MacLean formulated an idea called the Triune Brain. To tell it in over-simplified terms, the idea describes how the human brain has formed as a result of evolution. Triune Brain Theory describes the brain in three parts: the reptilian brain, the mammal brain, and the human brain.
The reptilian brain — that developed earliest in our evolution — manages repetetive tasks, motor skills, and physical survival. This is the part of the brain that controls heartbeat and breathing. It's obsessive and compulsive, and always active, even during deep sleep. The reptilian brain is the oldest, and deepest-seated part of the brain, and its needs trump all else.
The mammal brain — those parts of the brain resulting from evolution as a mammal — manages emotion, instinct, fight-or-flight, sexual behavior, and long-term memory. All emotion is generated in the mammal brain: happiness, sadness, fear, excitement, loyalty, trust, belief, positivity, negativity.
The human brain — those left and right hemispheres most highly-evolved only in the heads of primates and humans — makes up more than two-thirds of the contents of our head, and provides us with such things as speech, reading, writing, logic, and pattern recognition. All of those higher functions which make us human take place in that giant outer layer of the brain.
Why the science lesson, Randy?
Maybe you're sitting there right now, wondering why I'm talking about all this theoretical neuroscience. Or, perhaps you happen to be a neuroscientist, and right now you're growing more and more frustrated and offended by my gross over-simplification of the names and functions of various parts of the brain. Well, you'll deal with it. This is, after all, a language blog, not a science blog. There is a point.
You see, if you go back and look at those descriptions, you'll notice that all the things that make up language reside there in the neocortex, aka the human brain. But there's one little problem with that... long-term memory is managed in the lymbic system, or mammal brain!
Short-term versus long-term memory
I hate to break this to you, but all factual knowledge is short-term memory. And so is language. All that studying you're doing, all that work you're doing, every time you do a vocabulary lesson, or conjugate a verb, or do a flashcard, you're working in the neocortex where memories just don't last very long. And that's why you're so frustrated with learning.
Look at that description again for the mammal brain: it's completely irrational! It's fully of emotion. Now think about that: if the part of the brain that retains long-term memory is irrational and emotional, why are you trying to use logical methods to remember things?
Emotion = memory
Long-term memories are the result of strong emotion. They are, essentially, emotional imprints on our brains. Think of any moment from your past... chances are, it had a strong emotion tied to it. I mean, does anybody ever remember "the day that nothing happened?"
So I think you can see where this is going. If you want to remember things long-term, you need to generate emotion. But the way that most people learn is by studying tediously ad infinitum until they generate the emotions of boredom, frustration, and disgust. Is it any wonder that language learning has such a low success rate?
Your native language
But that's not how you learned your native language. You have memories. When I say the word "cake", I still remember my fifth birthday. When I say "box" I think of how many times I've packed and moved. And when I say "fall", I think of a 160-foot (50m) drop into a safety net.
These are the natural results of events that happen in life, usually by accident or by chance. But there's no reason they couldn't also happen by design! All you have to do is experience something while using your target language. It might be a fun experience, or a scary situation, or romance, or anger, or heartbreak, or laughter.
The key is to have experiences while using the language. This, more than anything else, is why it's so important to use your language as much as possible. Read stories, watch movies, listen to songs, chat, talk, meet people, have conversations.
It's been said that you must use a new word 20 times before you can remember it, but I guarantee you will remember it well after just one time, if it accompanies an experience. Maybe it's time you stopped studying and started living.