This study investigates the learning and memory of pain.

Inclusion Criteria:

1. Male and female healthy volunteers.
2. 18-65 years of age.
3. Right-handed.
4. Fluency in English. Ability to read and understand English; English can be a second language provided that the participant feels that he/she is able to understand all the questions used in the assessment measures.

Exclusion Criteria:

1. Any previous experience with conditioned analgesia/hyperalgesia paradigms.
2. Presence of any illness or medication use that is judged to interfere with the trial. For example: psychiatric disorder according to the DSM-IV manual, medication that can influence cognition or emotional processing, i.e. sleep medication, antidepressants, anti-convulsants or opioids.
3. Unwillingness to receive brief pain stimulation administered by a heat probe on the hand.
4. Instability of responses to experimental heat pain
5. Any contraindications to fMRI scanning for subjects in Experiment 2 (including metal implants, claustrophobia, history of head trauma, and pregnancy).
6. Peripheral neuropathy.