The crossed extension reflex shows that noxious stimuli can cause a spread of excitation that involves adjacent segments on the same and on the opposite side of the cord. Further, it has been suspected from the spread of deep pain from visceral disease that similar spread of excitation involving adjacent segments of the cord might occur. However, as far as can be ascertained, it has never been demonstrated that such spread involving sensation occurs at the segmental, rather than at a suprasegmental, level.1
The following data are evidence as to the site of occurrence in the neuraxis of the spread of excitatory processes from deep painful stimulation of high intensity.
F. W., a lawyer aged 48, had been found in 1940 to have a papilloma of the bladder, causing hematuria. The lesion was treated endoscopically by fulguration. With a recurrence of symptoms, he was admitted for the
RAY BS, WOLFF HG. STUDIES ON PAIN"SPREAD OF PAIN"; EVIDENCE ON SITE OF SPREAD WITHIN THE NEURAXIS OF EFFECTS OF PAINFUL STIMULATION. Arch NeurPsych. 1945;53(4):257-261. doi:10.1001/archneurpsyc.1945.02300040003001