title: A neural mechanism for exacerbation of headache by light.
abstract: The perception of migraine headache, which is mediated by nociceptive signals transmitted from the cranial dura mater to the brain, is uniquely exacerbated by exposure to light. We found that exacerbation of migraine headache by light is prevalent among blind individuals who maintain non-image-forming photoregulation in the face of massive rod/cone degeneration. Using single-unit recording and neural tract tracing in the rat, we identified dura-sensitive neurons in the posterior thalamus whose activity was distinctly modulated by light and whose axons projected extensively across layers I-V of somatosensory, visual and associative cortices. The cell bodies and dendrites of such dura/light-sensitive neurons were apposed by axons originating from retinal ganglion cells (RGCs), predominantly from intrinsically photosensitive RGCs, the principle conduit of non-image-forming photoregulation. We propose that photoregulation of migraine headache is exerted by a non-image-forming retinal pathway that modulates the activity of dura-sensitive thalamocortical neurons.
authors.affiliation: Department of Anesthesia, Boston, Massachusetts, USA.
authors.forename: Rodrigo
authors.initials: R
authors.lastname: Noseda
authors.forename: Vanessa
authors.initials: V
authors.lastname: Kainz
authors.forename: Moshe
authors.initials: M
authors.lastname: Jakubowski
authors.forename: Joshua J
authors.initials: JJ
authors.lastname: Gooley
authors.forename: Clifford B
authors.initials: CB
authors.lastname: Saper
authors.forename: Kathleen
authors.initials: K
authors.lastname: Digre
authors.forename: Rami
authors.initials: R
authors.lastname: Burstein
mesh_terms: D000328:Adult; D000818:Animals; D001369:Axons / Q000502:physiology; D001766:Blindness / Q000453:epidemiology / Q000503:physiopathology; D002540:Cerebral Cortex / Q000503:physiopathology; D003712:Dendrites / Q000502:physiology; D004388:Dura Mater / Q000503:physiopathology; D005260:Female; D006801:Humans; D015994:Incidence; D008027:Light / Q000009:adverse effects*; D008297:Male; D008881:Migraine Disorders / Q000453:epidemiology / Q000209:etiology* / Q000503:physiopathology*; D009434:Neural Pathways / Q000503:physiopathology; D009474:Neurons / Q000502:physiology*; D015995:Prevalence; D051381:Rats; D012160:Retina / Q000503:physiopathology*; D012165:Retinal Ganglion Cells / Q000502:physiology; D013788:Thalamus / Q000503:physiopathology*