We all know about 'spatial intelligence' and we also know that some people are better at visualizing than others. I know for example, that when I'm awake, it's very difficult for me to visualize in 3-D and consequently, I have ruled out engineering in favor of a physical science due to my poor spatial abilities and poor visual memory (are they extremely important in physics/astronomy though?) But on the other hand, we can all visualize clearly when we are dreaming. Do we all have a hidden ability to visualize in 3-D, even if our abilities are very poor? And is there a way to take advantage of that ability? One thing is known - some people with brain damage sometimes gain some phenomenal abilities, such as the ability to know the name of the day of a future or previous date in their head.