Werner Herzog is currently being criticised for his free adaption of a true story of a captured American flyer in the 1960's - he portrays someone as a gibbering idiot and his family are anxious to point out that he absolutely wasn't like that. But Herzog's subsequent film 'Wild Blue Yonder' - very snooze-worthy - employs this same motif several times. My understanding - and it's a tedious but clever work - is that it symbolises human mind, or brain, and the entry path is that empty space between the two spheres.