|SECTION 1 OF 8||  [3.1] [3.2] [3.3]     [Ap]||DOWNLOAD PDF|
R L Gregory and J G Wallace
Reproduced from Experimental Psychology Society Monograph No. 2 1963
This is the case history of a man born in 1906 who lost effective sight in both eyes at about ten months of age, and after fifty years as a blind person received corneal grafts to restore his sight. Such cases are rare, and few have been investigated in any detail, or have available pre-operative records giving their early history. Since cases of recovery from congenital or early blindness have been discussed by philosophers for over three hundred years, and have more recently attracted the interest of experimental psychologists, we feel justified in presenting in full everything which might be regarded as relevant to the case.
René Descartes (1596 - 1650) in a famous passage in his Dioptrics (1637), considers how a blind man might build up a perceptual world by tapping objects round him with a stick. He first considers a sighted person using a stick in darkness, and says "... without long practice this kind of sensation is rather confused and dim; but if you take men born blind, who have made use of such sensations all their life, you will find they feel things with perfect exactness that one might almost say that they see with their hands ..." Descartes goes on to argue that normal vision resembles a blind man exploring and building up his sense world by successive probes with his stick.
John Locke (1632 - 1704) once received a letter from Molyneux in which was posed the now celebrated question: "Suppose a man born blind, and now adult, and taught by his touch to distinguish between a cube and a sphere of the same metal. Suppose then the cube and sphere were placed on a table, and the blind man made to see: query, whether by his sight, before he touched them, could he distinguish and tell which was the globe and which the cube? . . . . The acute and judicious proposer answers: not. For though he has obtained the experience of how the globe, how the cube, affects his touch, yet he has not yet attained the experience that what affects his touch so or so, must affect his sight, so or so. . . ." In the Essay Concerning Human Understanding, 1690, (Book 11, Chapt. 9, Sect. 8) Locke comments as follows: - " I agree with this thinking gentleman, whom I am proud to call my friend, in his answer to this his problem; and am of the opinion that the blind man, at first, would not be able with certainty to say which was the globe, which the cube. . . ."
Bishop George Berkeley, (1685 - 1753) in his A New Theory of Vision (1709) distinguished carefully between sight and touch as ways of perceiving and knowing, and took the hypothetical case of recovery from blindness in the following way: - "In order to disentangle our minds from whatever prejudices we may entertain with the relation to the subject in hand nothing is more apposite than the taking into our thoughts the case of one born blind, and afterwards, when grown up, made to see. And though perhaps it may not be an easy task to divest ourselves entirely of the experience received from sight so as to be able to put our thoughts exactly in the posture as such a one's: we must nevertheless, as far as possible, endeavour to frame true conceptions of what might reasonably be supposed to pass in his mind" (op. cit. Sect. XCII). Berkeley goes on to say that we should expect such a man not to know whether anything was "high or low, erect or inverted . . . for the objects to which he had hitherto used to apply the terms up and down, high and low, were such only as affected or were some way perceived by his touch; but the proper objects of vision make a new set of ideas, perfectly distinct and different from the former, and which can in no sort make themselves perceived by touch" (op. cit. XCV). He goes on to say that it would take some time to learn to associate the two.
In 1728 Cheselden presented the celebrated case of a boy of thirteen who gained his sight after removal of the lenses rendered opaque by cataract from birth, but this was not by any means the first successful operation of its kind: the earliest reported dates from A.D. 1020, of a man of thirty operated upon in Arabia. Other cases were reported in: 1668, 1695, 1704 and 1709. [ Footnote 1 ] After the Cheselden case of 1728, we find some fifty cases up to the present day, one of the most recent being that of Latta, 1904. [ Footnote 2 ]
The evidence provided by the famous Cheselden case was discussed by Julien Offray de la Mettrie (1709 - 1851) in his Natural History of the Soul (1746) [ Footnote 3 ]. De la Mettrie argues that only education received through the senses makes man man, and gives him what we call the soul, while no development of the mind outwards ever takes place.
The published cases have been collected and described by Herr M. von Senden in his book: Raum- und Gestaltauffassung bei operierten Blindgeborenen (1932), which was virtually unobtainable in this country before the recent and most welcome translation, arranged by Miss Sylvia Schweppe and undertaken by Mr. Peter Heath, entitled: Space and Sight (Methuen, 1960).
The importance of these cases has been stressed by many classical writers, including Hume and Helmholtz, and most recently by the psychologist D. O. Hebb, in his influential book The Organisation of Behavior (1949). Hebb cites the von Senden collection of cases, and makes a great deal of use of them in developing a theory of the development of perception. We shall later consider Hebb's arguments and conclusions.
Operable cases of blindness - strictly near-blindness for the retina must be functional and eye tissues are never entirely opaque - are of two kinds: cataract of the lenses and opacity of the corneas. The former was treated from early times by slitting the eye ball and removing the lens; treatment of corneal opacity is recent and involves highly skilled grafting of a donated cornea. All the earlier cases are therefore cases of cataract, while some of the more recent - including the one to be described here - were rendered blind, or nearly blind, by opacity of the corneas.
With improvement in operative technique, and also a more ready supply of corneas, it has become extremely rare to find a case of very early blindness which remains untreated after the first few years of life. The case to be described - that of S.B. - is exceptional because he was regarded for many years as inoperable, until finally an attempt, and a successful attempt, was made when he was fifty-two years of age. We can hardly expect such a case to recur in the near future, and so it is unfortunate that no experimental psychologist was informed of the case until after the corneal grafting took place. If another such case should occur, we hope that it may be possible for an investigation to be initiated some time before the operation is undertaken. A later investigator may be able to learn something from our evident mistakes.
It is unfortunate that very few of the published accounts of recovery from early blindness describe any detailed observations or tests made on the patients. It is also far from clear how much residual vision they had prior to the operation. At the time we undertook the enquiry, we had but the most sketchy knowledge of the literature. We knew of von Senden's work from summaries and accounts, but had not seen the original, which was not then readily available in this country. We did, however, set out to try some reasonably objective tests, though these we had to prepare with only a few days' notice as we were anxious to see the patient as soon as possible.
continues with Section 2 - The Case of S.B.