Is it possible to raise the complexity of what you can mentally process?
I think the answer you are looking for is chunking.


  A chunk is defined as a familiar collection of more elementary units
  that have been inter-associated and stored in memory repeatedly and
  act as a coherent, integrated group when retrieved (Tulving &amp; Craik,
  2000). It is believed that individuals create higher order cognitive
  representations of the items on the list that are more easily
  remembered as a group than as individual items themselves.


The repeated exposure unconsiously creates chunks of many elements that are stored in long term memory, which are retreived as whole units in the working memory. In this case the limit is 3-4 chunks, each composed of many elements.

It is sometimes possible though, if needed, to consiously decompose the chunk into its elements in working memory, but in this case only 3-4 items of the decomposed chunk can be active in the working memory.