Allodynia: lowered threshold: stimulus and response mode differ
Hyperalgesia: increased response: stimulus and response mode are the same
Hyperpathia: raised threshold: stimulus and response mode may be the increased response: same or different
Hypoalgesia: raised threshold: stimulus and response mode are the same lowered response:
The above essentials of the definitions do not have to be symmetrical and are not symmetrical at present. Lowered threshold may occur with allodynia but is not required. Also, there is no category for lowered threshold and lowered response - if it ever occurs.
Link
