* As we are well aware, our visual system
is easily fooled when scenes and images are seen out of context. We rely
on cues such as receding lines to see depth, and when an image with depth
is taken out of context, we can get confused.
* Lateral inhibition is very powerful phenomena
and can help explain why we see the illusions the way we do.
Poggendorf's Illusion is not yet fully
explained. The two theories I've presented do not fully explain why we
can't match up the lines properly, so there is still more research to be
done.
An interesting thing to note is that people
do not get better at working through Poggendorf's Illusion with multiple
trials. (1)
(1) DO PEOPLE GET BETTER
AT THE POGGENDORF ILLUSION?
http://www.mercer.edu/camps/message/summer2000-poggendorf.htm
(2) Carulli, Venuta. Poggendorf
Explained
http://www.slc.edu/~vcarulli/pogg.html
(3) Internet Psychology
Lab, University of Illinois
http://kahuna.psych.uiuc.edu/ipl/vis/poggendorff/level_3.html
(4) Vincenzi, Ph.D. Dennis
A. , Poggendorf Illusion,
http://faculty.erau.edu/vincenzd/hfs615/poggendorf.htm