Visualization is the ability to “see things” in your brain. Visualization is the ability to draw a picture in your mind’s eye.
Visualization is a fundamental and powerful spiritual technique. Visualization is quite literally the steering wheel of creation (ref. GA).
Visualization is the key to manifesting imagination in the world (Sharp, STARS). The Little Book of Stars
Negative Visualization is an oxymoron. Negative visualization does not work.
Sharp, Michael (GA). The Great Awakening: Concepts and Techniques for Successful Spiritual Practice.
Sharp, Michael (BOOK1). Lightning Path Workbook One: Introduction to Authentic Spirituality. Lightning Path Press. 
Sharp, Michael (BOOK3). Lightning Path Workbook Three: Connection. Lightning Path Press.