1902 Encyclopedia > Aphasia

Aphasia




APHASIA (from the Greek a and phasis; synonyms, Aphemia, Alalia, Aphrasia, Aphthongia, Aphthenxia), a term applied to indicate a condition in which the function of expressing ideas by articulate sounds is arrested, perverted, or destroyed, in consequence of lesion of the brain. Loss or perversion of the power of expressing ideas by written signs is often associated with this condition. The term Aphasia is generally held to comprise two great varieties: (1), Amnesic Aphasia, in which the memory of words is lost or perverted; and (2), Ataxic Aphasia, in which the function of articulation is lost or perverted. Although this broad distinction is very properly made, it very rarely happens that a case occurs in which the two conditions are not to a greater or less extent coexistent.

Amnesic (Greek a, mnesis) aphasia is symptomatised very variously. The earliest and most common indication consists in – (a.) The loss of the memory of substantives and names, other parts of speech being properly applied; in such cases a periphrasis is employed to express the term. (b.) The memory of a language with which the patient had been thoroughly conversant may become lost. (c.) Terms are persistently misapplied; for instance, in recorded cases "pamphlet" has been used for "camphor," "hogshead" for "sugar," "horse" for "man," &c., &c. This symptom has been named Heterophasia (Greek heteros, phasis). In ataxic (Greek a, taxis) aphasia – (a.) the function of articulation is completely lost, the patient being only able to indicate by signs that he is conscious of the idea conveyable by the term; thus an ataxic aphasic, who had been an engine-driver, when asked what had been his trade, could only express himself by imitating the sound made by and engine when starting, "Hish, h! ish, hish." In many instances even this power of imitation is in complete abeyance-assent to the fitness of a spoken word to indicate the object exhibited being given by a nor or other gesture. (b.) The function of articulation is modified; thus a word may be only half articulated; for instance "watch" can only be pronounced as "wa," no prompting, or effort on his own part, enabling the patient to complete the word. (c.) Only automatic phrases can be articulated, oaths, "yes," "no," "aye," &c. (d.) The patient makes use of a set phrase, which may consist of actual words, but more frequently of confused sounds, such as "tan tan," "ta ta," "didoes doe the doe," &c.; but such phrases do not appear to satisfy him as expressive of ideas, although only one is persistently employed. In almost all cases of ataxic aphasia there is a well-marked desire and effort to enunciate words, the muscles of articulation often working strongly but convulsively. The great diagnostic point between amnesic and ataxic aphasia is, that in that former the patient can always articulate the forgotten word when it is suggested to him; in the latter, no prompting or assistance can enable him to enunciate the proper sound. Closely associated with both forms of aphasia is the loss of the power of expressing ideas by written signs. To this condition the term agraphia (Greek a, graphein) has been applied. Most frequently this power is completely lost, the effort of putting pen to paper being only followed by a confused scribbling; occasionally a strong effort is made to write; for instance, the patient makes a feeble endeavour to make his signature, which results in the production of a badly-formed initial letter, the subsequent ones being either quite unformed, or represented by a confusion of wrong signs. In the most slightly-marked cases of agraphia, i.e., those in which the patient is able to produce actual graphic signs, the general character of the handwriting is completely changed from that which had existed during health.

Aphasia, whether amnesic or ataxic, may, but seldom does exist disassociated from absolute insanity.

Great interest has centred around the question of the pathology of aphasia, as many observations have been adduced which appear to connect with this condition lesion of a specific portion of the brain, and from this it has been sought to deduce the absolute localisation of the function of speech in the hemispherical ganglia. The large proportion of cases of ataxic aphasia occur in association with right-sided hemiplegia, although others are on record in which it has appeared in connection with left—sided hemiplegia in left handed persons. Bouillard, Andral, and Dax placed on record a series of cases which bore upon the association of disease of the frontal lobes of the brain, with loss of the faculty of articulate speech. In 1861 Broca of Paris enunciated the theory, founded on the clinical and pathological observation of two carefully reported cases, that the portion of the cerebrum which is necessarily diseased in aphasia is the posterior third of the third or inferior left frontal convolution. A large number of cases have since been published which appear to support this theory; but an almost equally large number have been recorded in which disease of this portion of the above- named convolution has been found without material impairment of speech, in which it has been found intact in cases of aphasia, or in which disease of other convolutions has been accompanied by similar symptoms. Broca’s positive localisation of the function of speech has been disproved by several well-authenticated cases; it is, nevertheless, held by many prominent pathologists, that, although his deduction is not absolutely correct, it is in the main true, as lesion of the portion of the brain indicated by Broca may affect neighbouring convolutions of the frontal lobes, in which their observations lead them to believe the function of speech is localized, although its seat cannot be exactly indicated. Another section of pathologists hold that the nutrition! of the whole encephalon is effected by lesion of this particular convolution, the locality of which, by its anatomical relations to the middle cerebral artery, is peculiarly liable to embolus and apoplexy, and that as a consequence, the faculty of speech is affected in common with other cerebral functions; and they further argue, that, as destruction of other portions of the cerebrum has been known to be accompanied by similar symptoms affecting speech (the left inferior frontal convolution being intact), it is in no wise proved that localization of function can be fairly deduced from the occasional association of lesion of this convolution with aphasia.

(See Dr. Bateman, On Aphasia; papers by Drs Tuke and J. Fraser in the Journal of Mental Science, 1870; Dr Ferrier "On the Localisation of Brain Function," West Riding Reports; and for bibliography, Dictionnaire Encyclopédique des Sciences Médicales. (J.B.T.)






The above article was written by Sir John Batty Tuke, M.D., D.Sc., M.P., Medical Superintendent, Saughton Hall Asylum, Edinburgh; Member of General Medical Council in Registration and Education; Medical Superintendent of Fife and Kinross Asylum, 1865-73; author of Morrison Lectures, Insanity and Over-exertion of the Brain.




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