Lecturer's Précis - Lichtheim (1885)

"On Aphasia"

Copyright Notice: This material was written and published in Wales by Derek J. Smith (Chartered Engineer). It forms part of a multifile e-learning resource, and subject only to acknowledging Derek J. Smith's rights under international copyright law to be identified as author may be freely downloaded and printed off in single complete copies solely for the purposes of private study and/or review. Commercial exploitation rights are reserved. The remote hyperlinks have been selected for the academic appropriacy of their contents; they were free of offensive and litigious content when selected, and will be periodically checked to have remained so. Copyright © 2010, High Tower Consultants Limited.

 

First published online 11:33 GMT 7th March 2002, Copyright Derek J. Smith (Chartered Engineer). This version [HT.11 - reinstate lost links] dated 12:00 8th December 2010

An earlier version of this material appeared in Smith (1996; Chapter 7). It is repeated here with minor omissions but supported with hyperlinks.

 

 

1 - "Lichtheim's House"

In 1885, the German physician Ludwig Lichtheim (1845-1928) contributed to the localisation debate by drawing a set of explanatory diagrams showing how the main language centres might be connected up. Like Wernicke, Bastian, and Charcot before him, Lichtheim placed auditory memories and motor memories in different centres (the "A" and "M" centres respectively), thus:

 

"We may call 'centre of auditory images' and 'centre of motor images' respectively, the parts of the brain where these memories are fixed." (Lichtheim, 1885, p435.)

 

A third centre, the "B", or concept, centre (from the German word Begriffe), took care of the semantic element of the equation. The beauty of the resulting diagram (Lichtheim's Figure 1 - now affectionately known as "Lichtheim's house" and reproduced below) is that a different aphasic syndrome naturally follows damage to any single pathway or any single centre. Thus [on some rows, onwards links are provided to the companion "Neuropsychology Glossary"] .....

 

Lesion

Syndrome

Further Detail

motor output pathway (5)

subcortical motor aphasia

 

acoustic input pathway (7)

subcortical sensory aphasia

 

acoustic-semantic link (6)

transcortical sensory aphasia

click here

semantic-motor link (4)

transcortical motor aphasia

click here

acoustic-motor link (3)

conduction aphasia

click here

acoustic centre (2)

sensory (or Wernicke's) aphasia

click here

motor centre (1)

motor (or Broca's) aphasia

click here

conceptual centre (B)

anomic or semantic aphasia

click here

(NB: The codes in brackets allow cross-reference to the Figure below.)

  

Figure 1 - Lichtheim's "House": Here is a diagrammatic summary of Lichtheim's opinions on how information flows during language processing. The code letters used are A = Acoustic Centre, B = Concept Centre, and M = Motor Centre. The numbers are Lichtheim's originals, and refer back to the lesions named above. The core argument is set out in the following quotation:

 

"The reflex arc consists in an afferent branch aA, which transmits the acoustic impressions to A; and an efferent branch Mm, which conducts the impulses from M to the organs of speech; and is completed by the commissure binding together A and M. When intelligence of the imitated sounds is superimposed, a connection is established between the auditory centre A, and the part where concepts are elaborated, B." (Lichtheim, 1885.)

 

More than a century later, Lichtheim's House remains the reference model of choice during medical school training for the Routine Neurological Examination. See, for example, Fuller (1993).

PIClichtheim1885a.gif

 

 

Redrawn from a black and white original in Lichtheim (1885, p436; Figure 1). This version Copyright © 2002, Derek J. Smith.

 

 

2 - "Lichtheim's Crown"

Lichtheim, incidentally, was also one of the first to recognise the diffuseness of the semantic system. In his Figure 7 (shown in Smith, 1996, at Figure 7.5), he divided the Begriffe centre up into a set of distributed but inter-connected "conceptual centres". This anticipated Freud's distributed object concept system, and the increasingly popular modern distributed memory models, such as (exactly a century later) the attribute domain model of Allport (1985).

 

Figure 2 - Lichtheim's "Crown": Comments as for Figure 1, but noting the physical separation of component elements of the B- system.

PIClichtheim1885b.gif

 

 

Redrawn from a black and white original in Lichtheim (1885, p478; Figure 7). This version Copyright © 2007, Derek J. Smith.

 

3 - Useful Links

Lichtheim's work was subsequently described by Head (1926) as being "the high-water mark" of the diagram-making approach to language localisation. For a more adventurous modern variant of the basic model, see what we have termed "McCarthy and Warrington's House" in McCarthy and Warrington (1984).

 

 

References

See the Master References List

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