Cognitive processes prospective gives 4 reasons why writing improves learning:

• Readers need to make “semantic and syntactic choices” that help them to organize their thinking and therefore enhances learning and knowledge gained
• Writing gives readers a tangible product that can be used to compare to other texts and thoughts, infer, and identify contradicting arguments
• Writing may require readers to make connections between topics and ideas that foster learning, especially when knowledge is represented in different formats
• Readers also need to consider potential audiences and form their thoughts in a way that makes sense, which sometimes requires re-arranging knowledge