There are so many imagery strategies. The most used and most effective strategy to enhance memory is visual imagery. It is the mental representation of the stimuli when it is not actually present. Different studies done in laboratories shows that the cerebral cortex gets actively charged activated during visual imagery.
The visual strategies are most effective. It is an associative type of learning. In this the person links a new unknown thing with known one. It forms a strong impression on his mind because of continuous learning or over learning. So, it can be retrieved when required. For learning a new vocabulary, we visualize the new word with its visual image. For example, when they study about an animal first, they create a mental picture and connect it.
There is also a strategy known as concept maps. We learn a concept by creating a map. There will be an aspect of critical thinking in concept maps. In this the individuals can think to their maximum and form new ideas or conclusions. We can also use it for memorizing vocabulary words for a foreign language. The method that would be least effective would be that Schemas which are the use of fundamental basis of thinking. They are systematic methods of action which allow us to think or the material facts and objects in the world. When we first hear a concept, a string of ideas forms in our minds about it. However, for study of foreign languages they may not be very useful. Therefore, the strategy of using schemes would not be useful for language studies.