I recently posted a video about the need for stacking layers of familiarity when learning a language. In other words, we need to be exposed to something dozens of times before it becomes familiar enough for us to hold onto and produce actively.
I've finally got around to reading Moonwalking with Einstein, which is a fun read and a good introduction to both memory techniques and the science of memory. In it, Joshua Foer describes a few studies done on image recognition by average people. Test subjects were placed in a room before a screen and subjected to rapid-fire image sequences, totaling thousands of images. Afterwards, these subjects could only actively recall a few images from the long sequence; however, in the next phase of the study, they showed that the memory of the images had, in fact, imprinted firmly in their memories. In part II of the study, two images at a time were presented to them on the screen — one from the original sequence, and one new image the subject had not seen before. The test subjects were able to identify with near 100% accuracy the images that had been in the original sequence and which images were new.
What does this mean for language learning? It means that material is going into your memory and making an impression if you don't know it. If we sit down and I explain the verbal system of a language in detail to the point where you feel so overwhelmed your head is about to explode… it is all still going in. You are laying that essential initial foundation upon which to stack more layers of familiarity. Get comfortable with the sensation of being overwhelmed, and continue the process of exposure. When you then feel comfortable, you can start storing material more actively in your memory so that you can recall it at will.