A case of dyslexia : a peculiar form of word-blindness / by James Hinshelwood.

  • Hinshelwood, James, 1859-1919.
Date:
1896
Catalogue details

Licence: Public Domain Mark

Credit: A case of dyslexia : a peculiar form of word-blindness / by James Hinshelwood. Source: Wellcome Collection.

Provider: This material has been provided by The Royal College of Surgeons of England. The original may be consulted at The Royal College of Surgeons of England.

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    mental effort. 4. No error of refraction, no affection of the fundus oculi, no muscular insufficiency or any ocular defect could be discovered on the most careful examination. It was therefore evident that this difficulty of reading was not due to any affection of the eye, but to some disorder of the visual centres in the brain. In the case already referred to as having been communicated by me last year the patient with normal visual acuity was unable to read any printed or written characters with which he was previously familiar with the exception of Arabic numerals. Similar cases having been described ever since Kussmaul’s article^ by the term “ word-blindness,” I adopted it as the most convenient word for briefly indicating the character of the case. Sir William Broadbent, in a critical note in The Lancet on my paper, has remarked that “ in his judgment the employment of the term ‘ word - blindness ’ has been misleading and unfortunate.” Now I quite agree with Sir William Broadbent that the word has frequently been used by writers loosely with different meanings attached to it and therefore it has been frequently misleading. The fault, however, lies, not in the word, but in the fact that those who use it have not always a clear conception of what Kussmaul meant by it. By the term “word-blindness” is meant a condition in which with normal vision, and therefore seeing the letters and words distinctly, an indi- vidual is no longer able to interpret written or printed language. With a clear understanding of this definition there is nothing misleading about the term, which is a most convenient one for describing a group of cases, which, how- ever, includes several different forms. All the varieties have this point in common, that the inability to interpret written and printed language is not dependent upon any ocular defect, but upon disorder of the cerebral visual centres. The case just recorded presents many striking points of difference from the case recorded by me last year. Both, however, belong to the group which embraces dis- orders of the cerebral visual centres and hence the present case has been described as a peculiar form or variety of word- blindness. Complete word-blindness involving absolute in- ability to interpret written or printed language (alexia) is due, as was pointed out in my last paper, either to a lesion in the visual memory centre, which occupies the left supra- 3 Disturbance of Sp^ech, Ziemssen’s Cyclopedia, vol. xiv., 1877. 4 The Lancet, Jan. 4th, 1896.