What do we know about drug tolerance? How are tolerances developed? How are they measured?
TOLERANCE IS LEARNED
http://www.nida.nih.gov/pdf/monographs/18.pdf
This is a government monograph in which investigations of drug tolerance to morphine using many behavioral (operant techniques) to assess tolerance are reported. Siegel's conditioning explanation is presented as one possibility.
CAN YOU DO BLOCKING?
http://www.uwp.edu/academic/psychology/demos/ClassOp/ClassOp.html
This applet provides a visual demonstration of the Rescorla-Wagner model. You will need to set the various parameters and then administer the tone/light/shock combinations in various formats. The results will show the level of conditioning. You can simulate overshadowing, blocking and other phenomena.
Theories are great, but can these theories be of use in the "real world"?