Relatively little is known in regard to the representation of the sacral segments of the cord in the cerebral cortex of man. Penfield and Boldrey1 (1937) recorded sensation in the opposite side of the penis following cortical stimulation but obtained no motor responses. They pointed out that the rarity of responses in the lower sacral and genital regions may be due to the comparatively small number of stimulations which the neurosurgeon is able to perform within the central fissure, or possibly to a false sense of modesty on the part of the patient. Scarff2 (1940) observed contraction of the anal sphincter in 1 patient after electrical stimulation of the medial surface of the cerebral hemisphere.
In contrast to the paucity of observations in man, the representation of the sacral segments has been worked out with considerable precision in the cortex of the monkey (Woolsey, Marshall and Bard,3
ERICKSON TC. EROTOMANIA (NYMPHOMANIA) AS AN EXPRESSION OF CORTICAL EPILEPTIFORM DISCHARGE. Arch NeurPsych. 1945;53(3):226-231. doi:10.1001/archneurpsyc.1945.02300030063010