What is the function of the right brain and why is it important in optical illusions?

Question

Since this is not my area of expertise, I searched Google under the key words "right left brain illusions" to get these possible sources:

http://www.illusions.1570films.com/
http://www.echalk.co.uk/amusements/OpticalIllusions/illusions.htm
http://www.moillusions.com/2006/04/left-brain-right-brain-magic-trick.html
(Broken Link Removed)
http://cwx.prenhall.com/bookbind/pubbooks/morris4/medialib/readings/split.html
http://www.members.cox.net/dagershaw/lol/Handedness.html

I hope this helps. Thanks for asking.

thanx for the help........
NOT