Well the answer is quite simple: When looking at a basic image, you are conscious at this moment of your effort to interpret the work someone has drawn with the intent of telling you something. By not relying on text we provide learners with the right amount of cognitive space to consider this image and make it their own (this is called active cognition).
Their mind examines this symbol and rapidly pairs it with existing situations stored in their sensory memory (parietal lobe). The ability to relate emotionally to a basic drawing (hippocampus region) allows you to commit meaning to this image. "Meaning" begins when your mind relates to this image as a valid event.
The more basic the drawing, the more "space" you give the students to retrieve their own meaning and therefore the more multilayered its interpretation becomes. Associating specific phonemes at the same this cognitive experience is taking place allows a deep encoding of the information and a rapid transfer from short to long term memory.
On a funny note...this is why do not ask me one more time if what we do is related to Rosetta Stone. This other language program invites learners to consider photographs and this teaching experience is very different with students unable to fragment and reconstruct their own sentences (but more about that another day...).
Where we part company with actual logographic reading such as Chinese characters, is the obvious fact that our icons were created to suggest an immediate and accurate interpretation. Chinese characters underwent many changes until their present state and barely relate to the initial concept they represent. However, both are logographic and follow the same neurological pathway notably through the occipital lobe and the Brocca area (areas of visual representation and speech comprehension).
Consider this: When you create a shortcut on your computer, this shortcut is actually empty, it stores no information. It is however an instant portal to a lot of information. Our icons are shortcuts on a page and allow your mind to access much more than just one word. You can easily reinterpret this word with its various prepositions or conjugation patterns. This is why we call it QTALK (phonetic for cue talk); Instant Recall Cues to Talk.