Hans Förstl


anton_1899

Gabriel Anton


Ueber die Selbstwahrnehmung der Herderkrankungen des Gehirns durch den Kranken bei Rindenblindheit und Rindentaubheit.


Archiv für Psychiatrie und Nervenkrankheiten, 1899, 32: 86 - 127.

On the Self-awareness of Focal Drain Diseases by the Patient in Cortical Blindness and Cortical Deafness


 
Ursula Mercz, a 56-year-old needlewoman, was treated in Graz Hospital for Nervous Diseases from 30th November 1894 until 29th May 1895. All we could find out regarding the previous history was that she has been frequently suffering from vertigo and headache, that even four years ago she had appeared changed to the people who were close to her, and that she had been completely unable to work for two years. The patient survived three spontaneous abortions. Some of the facts from the medical findings shall be emphasised. The patient's movements, particularly walking, were severely handicapped by pain; almost all of her nerve-trunks were extremely sensitive to pressure, particularly alongside the spinal column.The bones showed striking mobility and flexibility. The face is symmetric, the pupils react promptly. The fundi are completely normal apart from increased tortuosity of the veins. All skin and tendon reflexes are lively. During conversation, it was soon realised that the patient could not remember various words, particularly names of objects, and that she preferred to use indirect descriptions (Umschreibungen). Whenever she used the wrong words, she soon became aware of it; this perception and the lack of ability to find expressions that she wanted to use, and that she was looking for, caused vivid and angry reactions. She found the expressions for her own spontaneous line of thought rather well. She had great difficulties with naming items from memory when prompted by the physician. She often asked to be put on the right track and not to be bothered. Sometimes the patient showed a minimally preserved visual field, but this finding was followed by complete blindness on the very same day. At the beginning of January [1895], she could sometimes see and recognised dim outlines of objects, e.g. a circle drawn on a board, a triangle, scissors, a red ribbon. This state was replaced by complete blindness although pupils and fundi remained normal. The patient could not distinguish light darkness, she could not perceive objects, either when close to or distant from her, even a sudden approach or quick intensive illumination did not elicit lid reactions.9 Her gaze stared into empty space; fixation could not be confirmed. It was very striking that the patient did not take any notice of extreme and, later on, complete loss of vision. The patient, who was otherwise complaining a lot, was almost unaffected by this loss. When objects were presented in front of her, she - probably according to habit acquired during recent years - immediately tried to touch them, but she did not make an effort to recognise something by looking at it. If the object was presented at some distance or if touching was prohibited, she gave it any name purely by guessing. It was obvious that she, like many blind people, had become an experienced guesser. Her language capabilities were certainly sufficient to permit this statement. When asked directly about her vision, she answered in vague, general terms, "people see better when they are young, that's just how it is.,, She confirmed, calmly and faithfully, that she could see the presented objects, whereas almost daily examination proved the opposite. She also claimed to see things that were not actually presented to her. The patient was not aware of her loss of vision, and this defect did not cause her any further thought or conclusions, neither sorrow nor dislike. And all this during a time when a missing name or remembering a word caused obvious pain.

A further striking symptom was her lack of spatial orientation. The patient could not find her way in a room where she had been lying for several weeks. She does not find the glass which is always standing at the same place beside her. She does not know where her dresser, her chair, etc., stand.  When asked where the door, the windows, the patients' dining table are she gives the wrong directions. Even auditory stimuli, which have certainly been perceived, could not be localised. She heard the ticking of a watch from a distance of 35cms, but she locates it next to her ear. Often she gives the wrong side from where she hears the sound and she cannot determine the side of the bed where the examiner, who is speaking in a loud voice, is standing. When she bumps violently against the frame of her bed, i.e. after tactile stimuli, she can find her way quite quickly. She often makes the wrong distinction between right and left in spite of lengthy consideration. On several days, the patient gave two wrong answers after being asked five times. It can be noted that the patient can localise touch and pain sensation on her body rather well. When asked to do so, she also touches her nose, her mouth, her ear, etc., quite skilfully. She can determine the position of her extremities and she imitates the movements and positions that are given to the contralateral extremities without gross mistakes. When told to do so, she is also able to draw circles and other figures in the air or to cut these figures from a paper with scissors. In her memory, the patient has retained her mental imagery (Gesichtsvorstellungen). She describes where she lived, her house, her animals, their sizes and colours, as far as her expressive capabilities allow. While doing so, she cried-but this was probably a normal emotion. She recognises the persons around her by hearing and touch. She does not make any attempt at all to form a visual image of these people. Her physical and mental condition deteriorated remarkably in May. The left side of her body became paretic. Only feeble pulsations could be felt over her right carotid. The patient died after a long coma (29th May 1895). 

Postmortem

(pp. 94) . . . No severe atrophy . . . cystic necroses primarily affecting the white matter of the left and right occipital lobes . . .  … [An ton discusses under the heading "Considerations" the nature of the problem. He refers to Dufour (1889) in stating that: ". . . patients with a unilateral visual loss also lose their feeling for the lack of this visual field (Hemianopsie nulle)." Friedrich Müller (1892) expressed similar thoughts. Anton goes on to remind the reader that hallucinations can occur in the hemianopic field. He concludes this section by stating that ". . . a central sensory impairment can only remain latent for the patient if further brain lesions are present. ,,


The anatomical main event is the interruption of pathways to other brain areas in smaller or greater distance; this is a breakdown of the functional relationships with other cortical areas. It is undoubtedly possible that the function of one part of the brain, which is not damaged itself, can be altered through other parts.
  …
Sometimes subcortical centres can represent the substrate of complex functions in the presence of cortical lesions . . . In case 11 (Ursula M.) we have to consider the possibility that cortical areas, which are cut off from the periphery, can be stimulated from other cortical areas . . . Microscopic examination has demonstrated a sufficient number of shorter and longer association pathways, which can, e.g., mediate stimuli from the temporal lobe to the fairly preserved visual centre.22 The question whether the patient misinterpreted these stimuli as genuine sensory perceptions . . . cannot be answered on the basis of a single case. We can also only surmise that preserved subcortical seeing and hearing-a major factor in lower animals-can elicit dark sensations, which mask the loss of conscious cortical sensory perception.

Summary of Post-mortern and Histological Findings

Apart from the lesions of the second and third occipital gyri of the posterior angular gyri, which could be recognised from the surface, there was a destruction of the largest part of the pathways leading from this level of the occipital brain to the other lobes. This affected the fibres of the fasciculus arcuatus and the connections with the frontal lobe (fasciculus fronto-occipitalis), which have not yet been examined sufficiently. The pathways connecting the cortical areas of the occipital brain were affected similarly, particularly the cortical and transversal occipital bundies. The short cortical connections, the fibrae propriae, were preserved far better. Furthermore, the radiations of the superior colliculus and of the lateral geniculate body were cut off in their largest superior parts. This was caused partly by the upper larger lesion and partly by a smaller lesion in the posterior temporal gyrus. In the same area, the largest part of the lower longitudinal bundle was also destroyed by both lesions, leading to a progressive degeneration and atrophy. The central terminals of the visual pathways, i.e. the cuneus and the calcarine fissure, were essentially unaffected, but the visual pathway was cut off, causing a degeneration of the optic radiation in this area. Therefore this centre was cut off from the periphery. Finally, the posterior part of the forceps corporis callosis was destroyed by the larger lesion and its fibres at the lateral ventricular wall degenerated. Therefore both occipital lobes were mutually disconnected. 
Considering the subcortieal parts, the superior colliculus and the lateral geniculate body showed a considerable atrophy on both sides, but the microscopic examination revealed normal optic tracts. The medial parts of the occipital lobes were basically well-preserved, particularly the "tapestry" of the wall of the ventricle, of the medial ventricular wall, and the extension of the fasciculus cinguli. 

(translated by Hans Förstl, Anthony David and Adrian Owen. A commented version was published in “Cognitive Neuropsychology” 1993)


1. Anton, G. (18%). In Communications of the Society of Physicians of Styria, 3, 8544.