To the Editors:
I appreciated Dr. Moran's letter to the editor (Moran, 2008) providing a more balanced background to the historical paper by De Almeida et al. (2007), which discussed Penfield's role in the decision to include mesial structures in temporal lobe resections. I agree that it is unclear whether Morris (1950, 1956) took the initial bold step to remove normal-appearing hippocampus, and that there is a tendency toward hagiography when Penfield's disciples write about his contributions. Given the rapidly developing field throughout the Americas and Europe at the time (see Gastaut, 1954; Baldwin & Bailey, 1958), it is equally likely that the approach evolved simultaneously at many centers, for reasons that have not been documented. In defense of the Montreal Neurologic Institute (MNI), however, Dr Moran is incorrect when he attributes Gibbs with the first EEG evidence that psychomotor seizures were of temporal lobe origin (Gibbs et al., 1948). I was taught by Murray Falconer to always say that Bailey & Gibbs (1951) were the first to perform temporal lobe resections on the basis of EEG evidence alone, but not because Gibbs was the first electroencephalographer to recognize the localizing value of anterior temporal EEG spikes, but because Bailey was the first neurosurgeon willing to operate on this evidence alone. Jasper & Kershman (1941) fully described temporal interictal EEG correlates of masticatory, olfactory, and visual auras, motor automatisms, and ictal “dreamy states” 7 years before Gibbs. Interestingly, Jasper republished this information in the 1941 textbook by Penfield & Erickson (1941), while Penfield concluded, in the same textbook (page 462), that “when an encephalograph (meaning pneumoencephalogram) shows no evidence of a lesion, either atrophic or expanding, in that area of brain in which the seizures are arising, as indicated by seizure classification, any operative procedure is probably doomed to turn out to be a negative exploration.” As Moran points out, the classic paper of Penfield & Flanigin (1950), on 68 temporal lobe operations, contained only three in which mesial temporal structures were removed, although the following year Jasper et al. (1951), the same year that the Bailey and Gibbs surgical paper appeared, published the EEG findings on these patients, including intraoperative electrocorticography, which captured a seizure originating in the mesial temporal lobe. My own conclusion when I was preparing a history of epilepsy surgery (Engel, 1993) was that Jasper fully understood the importance of mesial temporal structures in the generation of what we now call complex partial seizures, but that Penfield paid little attention to the EEG and directed his surgical resections entirely to removal of structural lesions. Before publishing this history, I sent the manuscript to Herman Flanigin, who was coauthor on both of the MNI papers, and his response was, “That's exactly what happened.”
Conflict of interest: I confirm that I have read the Journal's position on issues involved in ethical publication and affirm that this letter is consistent with those guidelines. I have no conflicts of interest with respect to this letter.