That book is amazing. I got it also when it first came out years ago. Although I unfortunately did not finish it, I remember two exercises that left me marked:

That book is amazing. I got it also when it first came out years ago. Although I unfortunately did not finish it, I remember two exercises that left me marked: First is the exercise of drawing the "column / two-faces" drawing. You can REALLY feel your two brain sides fighting while drawing that. The second is the "upside down" drawing. After I finished that I was amazed that I actually had drawn that (I cannot draw a cup or a house or whatever). The premise is that a lot of people who have the "left" side of the brain developed draw the "concepts" of what they see and they don't really draw what they see. So if someone tells me to "draw that house", I will be drawing "a roof", "a door" , "the walls" etc. Instead someone using the "right" side of the brain will actually see the house and draw what they see. Pretty clever.