Electroencephalographic alterations in migraine as an expression of "self-deafferentation": a hypothesis

The deafferentation of a leg in animal is followed by: local analgesia; generation in spinal cord and brainstem (along the sensitive fibers of second order) of quasi epileptic foci emitting continuously and/or in bursts, epileptic-like discharges; scratching, attacks and finally autocannibalism of the deafferentated arm. This perverted behavior (autotomy) is attributed to an emission from the quasi epileptic foci of pain signals projected to deafferentated regions by cognitive sites of consciousness. The quasi epileptic foci, generating bursts of "automatic" pain, are considered the basic mechanism of pain in deafferentated and amputated humans. The nature of pain in migraine is assumed here as an analog to the mechanism of organic deafferentation; a generation in the brainstem of nociceptive foci, with the head as main projection. The enigmatic epileptic-epileptoid characteristics of EEG in migraineurs could be an expression of the electrically hyperactive "quasi epileptic foci" located mainly within the brainstem and generated by the insufficient opioid inhibition of sP-ergic neurons.