Pain sensitivity and headache: an examination of the central theory.

The central theory of headache was investigated by examining pain sensitivity in headache sufferers and headache-free controls. Headache subjects had lower pain threshold and tolerance levels than controls for electrical stimulation of the finger. Headache subjects also had a lesser tolerance for pain induced by the application of ice to the temporal region, but there was no significant difference between groups on temporal ice pain threshold. Sensitivity to finger pain was not affected by the presence or absence of headache at the time of testing. No significant differences between tension and migraine subjects were observed; neither were headache subjects, reporting unilateral headaches, significantly more sensitive to temporal ice pain on the side affected by headache. It was concluded that headache sufferers may be more sensitive to pain than headache-free persons but, that this heightened sensitivity is not specific to the head, and in itself, seems unable to account for the locus of headache.