I found the below images while reading the Boston Globe.  (Boston Globe?!)

These are great little examples of how you can trick your senses into perceiving things that you know are not real.  The experiences produced by the experiments are something much like hallucinations.

Try them out for yourself! 

The Ganzfeld Procedure

Incredible Shrinking Pain

The Rubber Hand Illusion

 
;

The Pinocchio Illusion

Purkinje Lights

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