Knowledge is stored in two forms – linguistic and imagery

The linguistic mode is semantic in nature. The linguistic mode contains actual statements in long-term memory. The imagery mode is expressed as mental pictures or physical sensations such as smell, taste, touch, kinesthetic association, and sound. Learning without reading….. 

The more we use both systems the better we are able to think and recall knowledge. This is particularly relevant in a classroom because studies have consistently shown that the primary way we present new knowledge to students is linguistic. We either talk to them about the content or have them read about the new content. Students are left to their own devices to generate nonlinguistic representations.