Malfunctions of the Brain
Probably the earliest published medical-scientific thinking on the topic of déjà vu is to be found in the 1844 book by the English doctor, Sir Arthur Wigan, on The Duality of the Mind. In 1817, he attended the funeral of Princess Charlotte at Windsor. He had had little sleep the night before and had eaten nothing during the day preceding the midnight interment (all inns and eating establishments were closed in mourning). After four hours of standing in St. Georges Chapel, he said he was very near fainting. Suddenly, as the coffin was being lowered into its place of final rest, he
"feIt not merely an impression, but a conviction [italics his], that I had seen the whole scene before on some former occasion, and had heard even the very words addressed to myself by Sir George Naylor." (p. 87)
From his experience, he derived the hypothesis that such experiences only occur when one is tired, so that one of the hemispheres of the brain is more or less inattentive to what is going on, or even asleep. Then something causes it to wake up, but it digests its information about the situation after the other, awake hemisphere has already acknowledged it. This produces the feeling of having known about it before. The time interval , he said, "may seem to have been many years" (p. 85), since we have nothing upon which to base our judgment of the elapsed time.
There have been several other authors with the same or similar ideas (e.g., Horwicz, Huppert, Jenssen, Wiedemeister, and Maudsley). One of the most recent revivals borrows electrical engineering language to speak of "the introduction of a delay network on apart of the input side" (Comfort, 1977. See also Efron, 1963). This theory did not, however, meet with general acceptance. It was criticized already by Sander in 1874 and more thoroughly by Kraepelin (1887) and Bonne (in 1907).
Another hypothesis in which the working of the brain is implicated is the long and well-known association of déjà vu with epilepsy (more specifically: psychomotor or temporal lobe epilepsy). This chapter in the history of déjà vu began in 1870 in a short, two paragraph paper in "The Practitioner" in which a young medical doctor using the pseudonym "Quaerens" wrote that he had often had déjà vu experiences as a boy, but that these had become "more intense and more frequent than usual" just preceding his first epileptic attack. He mentions that the latter had been triggered in a time of overwork, which would indicate that fatigue was also involved as a factor (see next sectionr), as with Wigan. He said that on two occasions, an incident of déjà vu was followed the next day by an epileptic seizure. Thus the surmise was at hand that there might be some connection between the two and that déjà vu could be indicative of an epileptic disposition.
Ten years (and some fifteen seizures) later, he became a patient of Dr. John Hughlings Jackson, probably the leading neurologist of his day, certainly in matters dealing with epilepsy. It was Jackson who coined the term "dreamy state" which, according to Bingley (1958), "is practically identical with the modern concept of psychomotor seizure" (p. 102). Déjà vu, or any inexplicable feeling on familiarity, was called by Jackson "reminiscence" (already in an 1876 lecture)(probably borrowed from Plato), and was included in what was known as "intellectual aura" or warnings which could precede or comprise an epileptic discharge. He had another patient, also a medical doctor, whom he designated "Z", who had similar symptoms. He called his "reminiscence" recollection and described it as
"What is occupying the attention is what has occupied it before, and indeed has been familiar, but has been for a time forgotten, and now is recovered with a slight sense of satisfaction as if it had been sought for. ... At the same time, or ... more accurately in immediate sequence, I am dimly aware that the recollection is fictitious and my state abnormal. The recollection is always started by another person's voice, or by my own verbalized thought, or by what I am reading and mentally verbalize; and I think that during the abnormal state I generally verbalize some such phrase of simple recognition as 'Oh yes -- I see', 'Of course -- I remember', &c., but a minute or two later I can recollect neither the words nor the verbalized thought which gave rise to the recollection. I only find strongly that they resemble what I have felt before under similar abnormal conditions." (Jackson, 1889, p. 202)
I have presented here this rather extensive quotation because it is characteristic of the familiarity feelings which occur sometimes in connection with temporal lobe epilepsy, and to show that the tone of it is strikingly different from accounts of déjà vu among those not afflicted with the "divine disease". I am personally inclined to believe that Quaerens had both déjà vu experiences and epilepsy, whereas Z had false familiarity feelings during his epileptic seizures. It may be of interest that it was later shown through autopsy that Z had, in fact, a "very small lesion of the left uncinate gyrus" within the temporal lobe (Jackson and Colman, 1898, p. 580).
In 1876, Jackson said, "It is well known that such sensations of 'reminiscence are not uncommon in healthy people, or in trivial disorders of health." (p. 702) And, further, in 1889,
"I should never, in spite of Quaeren's case, diagnose epilepsy from the paroxysmal occurrence of 'reminiscence' without other symptoms, although I should suspect epilepsy, if ... [it] should occur very frequently" (p. 186).
Despite such admonitions, Sir James Crichton-Browne in his 1895 Cavendish lecture before the West London Medico-Chirurgical Society on "Dreamy Mental States" maintained that occurrences of "reminiscence" must be seen as pathological. From the literary quotations he presented (from twelve different writers!) it is clear that he was referring primarily to déjà vu. He said that it was difficult obtaining information about such experiences, because those having had them were disinclined to talk about them, "from a not unwarrantable suspicion that they are somehow morbid in their nature." (p. 2) He quoted Quaerens and some of Dr. Jackson's patients, as well as some of his own, to show what sort of epilepsy he was considering. He went on to point out that Scott, Dickens, and Rossetti all died of brain disease, though he neglected to mention which variety. He finished by saying that such disturbances should be watched for in young people and treated as one would "cerebral neurasthenia and epilepsy" (p. 75). He especially recommended "rest and liberal nourishment", the latter being vegetarian, if possible. Dr. Foster Kennedy, in his 1911 paper, seems to have adopted these views in toto.
Thus it is that up until recently, if one spoke of déjà vu with a medically trained person, especially a neurologist or psychiatrist, his first reaction would have been to think of possible temporal lobe epilepsy. Not only did Jackson lump déjà vu with false familiarity into his concept of "reminiscence", but others following him have tended to form their diagnoses on the bases of such historical accidents and anecdotes, rather than on scientific statistical evidence.
Fortunately, for those who wish to look into it, the necessary studies have been carried out. In 1933, Lennox and Cobb made a statistical study of the incidence of aura in all types of epilepsy. 1359 cases were reviewed and it was found that 764 (or only 56.2%) experienced some sort of aura in connection with their epileptic seizures. Of these, 750 described their aura and these descriptions were analyzed into 327 different categories. 167 had two or more symptoms, so that altogether, 1059 were tabulated. Of these, 3 felt that they were repeating former experiences, 1 (!) had the sense of having seen (déjà vu), and 1 experienced a dreamy state. We saw already in chapter one that roughly three out of every ten persons have had some experience resembling déjà vu (this probably includes feelings of false familiarity). Thus the incidence of déjà vu as part of an epileptic attack is amazingly low! Considering tumors of the temporal lobe, Keschner et ale published a study in 1936 of 110 cases and found no déjà vu in connection with this affliction. They did have two cases where "dreamy states" were noticed, however.
In 1944, Herman and Stromgren examined the records of 644 patients admitted for neurosurgery in Copenhagen. 322 exhibited disturbed consciousness symptoms and hallucinations. They narrowed these down to 68 for intensive study (34 men and 34 women). With regard to déjà vu (which they term "increase of recognition"), there were 8 instances (12%) and the temporal lobe was involved in only 3 of them. Their conclusion is that it cannot be used to pinpoint the source of the disturbance in the brain.
Bingley, in 1958, reviewed studies of dreamy state incidence in temporal lobe epilepsy and tumors and added the results of his own observations with 90 patients. He found 12 (13%) with illusions of memory, "mostly of the déjà vu type" (p. 106). Finally, Richardson and Winokur in 1968 showed that among neurosurgical patients, no one type reported having déjà vu experiences with a significantly higher incidence than the others, and that the incidence among neurosurgical patients was not significantly greater than among psychiatric patients.
Such results need to be more widely disseminated. In my opinion, only ignorance of them could permit an otherwise immanently capable neurologist to write nonsense like the following:
"Only the temporal lobe epileptic with his faulty assessment of time and coincidence has the feeling that he knows the words almost before they are uttered by the speaker." (Simpson, p. 48)
And this is 1969!
This chapter on the possible organic basis of déjà vu would not be complete without mentioning the important and fascinating work performed in Montreal and published by Dr. Wilder Penfield and his associates. They have treated surgically numerous patients afflicted with various types of epilepsy. Given the opportunity of an exposed cerebral cortex, they have used electrodes to stimulate the brain in an effort to better localize the malfunctioning area. Only in stimulating the temporal lobes have they elicited experiential responses from patients under local anesthesia (Penfield and Perot, p. 601). In 70, out of 214 temporal lobe investigations, they obtained what they term "psychical illusions" or "illusions of comparative interpretation". Under this heading, they include: 1) auditory illusions, 2) visual illusions, 3) illusions of recognition, and 4) illusional emotions (Mullen and Penfield, 1959).
The third category embraces both illusions of familiarity (déjà vu included) and illusions of strangeness, change, and unreality. In 6 patients, they were able to induce false familiarity feelings through gentle electrical stimulation of the temporal lobe on the non-dominant hemisphere. The sites are depicted. The accounts of two such patients reporting on their experiences while being stimulated are given and they sound very much like déjà vu (pp. 275 - 277). It is not entirely clear, though, that déjà vu episodes were what were elicited (and the authors carefully nowhere say that they were). It could be that persons who have had numerous déjà vu experiences would interpret an illusion of familiarity as being the same thing, since they are similar.
On page 281, in discussing their results, Mullen and Penfield make the observation:
"Unlike auditory illusions, these feelings of familiarity did not occur without having been present in the seizure, a feature that suggests that considerable 'conditioning' in the abnormal temporal lobe was necessary for the production of these feelings. ... [T]hey were found over a fairly wide area, and this was true even in a single subject, indicating, perhaps, that the function of estimation of familiarity has a diffuse representation throughout the temporal lobe." In one case, the illusion of familiarity seemed to be produced on the dominant side. It is interesting that the false familiarity feelings only arose in those pre-disposed for them.