Static Mechano-allodynia and Temporal Summation: Static mechano-allodynia and temporal summation will be determined by pin-prick with a standard safety pin once every three seconds for a total of 5 times. The subject will be instructed to report the level of pain on a 0-10 scale (0: no pain; 10: worst pain ever experienced) and the extent to which the sensation spread after each repetition. The test will stop if the subject reports unacceptable pain at any point during the test.