Course Handout - Neuropsychology Timeline
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First published online 12:14 BST 28th August 2002, Copyright Derek J. Smith (Chartered
Engineer). This version [HT.1
- transfer of copyright] dated 18:00 14th January 2010
An earlier version of this material appeared in Smith
(1996; Appendices A to C). It is repeated here with minor amendments and
supported with hyperlinks.
1 - Neuroscience Before 1861
The
following early contributions to neuroscience are worth noting:
Anonymous - The "Ebers"
Papyrus: This ancient Egyptian document dates from about 2500BC,
and describes a case of head injury who had lost his ability to speak without
paralysis of his tongue (cited in Hecaen and Albert,
1978, p13).
Anonymous - The "Edwin Smith" Papyrus: This ancient
Egyptian document (named after the archeologist who dug it up in 1862) dates
from about 2500BC, and has been called the oldest
medical "textbook" on earth. It presents 48 case studies, including
head injuries and broken bones. It includes the first recorded use of the word
"brain" (Breasted, 1930), and records both lateralised
skeletomuscular impairments and loss of speech. [For
more on this, see the Cyber Museum of Neurosurgery.]
Alcmaeon (Greek physician):
According to Williams and Warwick (1975), the first to describe the optic
nerves (ca 500BC).
Hippocrates (Greek physician: 460-370BC): Apart from introducing the Hippocratic Oath,
Hippocrates stated that the brain (and not the heart, as many thought at that
time) was the seat of sensation, thought, and the emotions. He also noted a
variety of conditions - epilepsy, etc. - where speech was likely to suffer.
Erasistratus (Alexandrian
physician: ca 300-250BC): Began human dissection and
equated the gyri of the brain with various facets of
intelligence (a suggestion described by Warwick and Warwick, 1975, as
"remarkably prophetic").
Pliny the Elder (Roman archivist: 27-79AD): In 77AD noted the
selective loss of memory with head injury. For example, a man who when struck
by a stone forgot how to read (Pliny, 77AD; Book VII,
Stanza 24.)
Claudius
Galen (Roman physician: 129-199AD):
Physician from 170AD to the Roman emperor Marcus
Aurelius, and author of over 400 early treatises on anatomy and physiology.
Served when young as resident surgeon at the gladiator school in
Gregor Reisch: (1467-1525): Located the faculty of memory
in the fourth ventricle.
Andreas Vesalius (Flemish
physician: 1514-1564): Vesalius was a renaissance anatomist. Since it was still
officially forbidden to dissect human corpses, he bought bodies from grave
robbers and conducted the first systematic dissections. These included
dissections of the NS. He recorded his findings in his textbook On the
Structure of the Human Body (Vesalius, 1543). This was a printed rather
than a hand-written book, and so was able to make anatomical drawings and
diagrams widely available at low cost and without transcription error. Many of
Galen's long-standing errors were exposed. Nevertheless Galen's works remained
the conventional wisdom, and for a while Vesalius suffered establishment
vilification and accusations of body snatching. In the end, however, his ideas
caught on and he is today credited with being the "father of modern
anatomy".
Rene Descartes (French
philosopher-mathematician: 1596-1650): Speculated on the relationship between
the mind and the brain, even going so far as to locate the seat of the soul in
the pineal gland. Used as his definition of human existence the Latin maxim cogito
ergo sum - "I think, therefore I am".
Robert Hooke (British physicist): In 1665
published Micrographia, one of the early
sources for the concept of the biological cell.
Sir Thomas Willis (British physician:
1621-1675): Published Anatomy of the Brain (1664), Pathology of the
Brain (1667), and The Mind of Animals (1672), describing the NS and
its blood supply. Declared the cerebellum to be an organ for the execution of
involuntary movements.
Johann Schmidt (German physician): In 1673
described a case of acquired alexia with preserved ability to write, thus
making him one of the first to record a dissociation of function [Neuropsychology Glossary]. Particularly fascinating
was the fact that this patient could successfully write to dictation, but could
not then read back what he had written.
Peter Rommel (German physician): In 1683
published a detailed description of a motor aphasia [Neuropsychology Glossary], terming it "a rare aphonia". The patient's understanding was intact, but
conversationally she was poor and unable to repeat even short phrases to
command. Curiously, though, she retained the ability to recite long and
well-learned Biblical passages.
Abbé Jean-Antoine Nollet (French priest: 1700-1770): Used electrical current
from "Leyden Jar" batteries (then only recently invented) to induce
muscle twitchings in newly hanged corpses and in the
living. In one demonstration he linked the hands of 180 men in a chain and sent
a shock from one end to the other. (Note that Nollet
also discovered the phenomenon of osmotic pressure, one of the factors involved
in maintaining the neural resting potential.)
Emanuel Swedenborg (Swedish
mathematician-physiologist: 1688-1772): In the period 1740-1744, collated and
reviewed the sum total of neurological knowledge to that date, and, in so
doing, noted the importance of the cerebral cortex as the top level of the
sensory and motor systems. He described it as the site of the "soul's
faculty of understanding, thinking, judging, willing". Also correctly
identified the pituitary gland as the "arch-gland" of the body, and
placed the production of CSF in the choroid plexuses.
Johann Gesner (German physician): In 1770
reviewed a number of case descriptions of patients with various language
defects. Gesner made an important contribution to aphasiology,
thus:
"He attributes aphasic
disorders not to a general intellectual decline or a general loss of memory, as
had been done so often by earlier writers, but to a specific impairment in verbal
memory. This impairment in memory consists in the inability of the patient to
associate images or abstract ideas with their conventional linguistic signs.
[These] "associationist" theoretical
conceptions, which are admittedly rather vague, might well be considered as
being the first statement of a modern theory of the aphasic disorders."
(Benton, 1964, pp319-320; emphasis original.)
Francesco Gennari (Italian
anatomist: 1750-1795): According to Spillane (1981) was the first (in 1776) to
note the tiny laminations in the visual cortex, thus laying the groundwork for
later investigations by Baillarger (see 1840) and Brodmann (see 1909).
Luigi Galvani (Italian chemist: 1737-1798):
Demonstrated in 1780's-90's that the muscle tissue of
a "dead" animal could be caused to twitch by the application of
electric current (Galvani, 1791). This, of course, smacked of "reanimating
the dead", and the experiments caused intense public interest, even
entering mainstream literature in the form of Mary Shelley's novel
"Frankenstein" in 1818.
Albrecht von Haller (Swiss physiologist:
1708-1777): In a series of textbooks published in the period between 1747 and
1776, described the circulation of the blood and the control of muscles by
nerves. He described the contraction of muscle under nervous influence as
"irritability". He regarded the cerebral cortex to be important, but
located the soul in deeper centres.
Franz-Joseph Gall (Austrian physician:
1758-1828): Lectured from 1802 on the "science" of phrenology, claiming (a) that different
parts of the brain have different functions (some truth), (b) that different
individuals could be differently endowed with these abilities (probably true,
although great caution is needed), and (c) that the individual extent of these
abilities could be gauged from the shape of one's skull (probably untrue).
These ideas were published in 1805 under the title On the Activities of the
Brain. Gall's position comes out well in the following quotation:
"I would often divide
[the lower classes] into three classes. The first would include the thieves;
the second, those who had an abhorrence of theft; and the third, those who
regard it with indifference. On examining their heads, I was astonished to find
that the most inveterate thieves had a long prominence, extending from the
organ of cunning, almost as far as the [] supraciliary
ridge; and that this region was flat in all those who showed a horror of theft.
[These cases] conclusively prove that the propensity to steal is not the result
of moral depravement, nor of a defective education, but
is an inherent quality in human nature." (Gall, 1805; emphasis
added)
While phrenology is now generally accepted as being
little more than charlatanism (Gray, 1948, calls it a "preposterous
notion" and a "persistent nonsense"), Gall and his associate Spurzheim (1776-1832) were actually quite accomplished neuroanatomists, and should not be dismissed out of hand.
Sir Charles Bell (Scottish physician: 1774-
1842): Published New Anatomy of the Brain in 1811. In it he analysed the organisation of the
spinal cord and proposed a fundamental distinction between sensory and motor
functions. The motor tracts, he claimed, ran ventrally.
Francois Magendie (French
physiologist: 1783-1855): In 1822 confirmed
"I was able with the help
of a very sharp scalpel to expose the posterior half of the spinal marrow. I
was able to cut the posterior roots of the lumbar and sacral pairs on one side.
[] I reunited the wound by a suture, and then observed the animal. I at first
thought the member was paralysed because it was
insensible to the strongest prickings and pressures.
But soon, to my great surprise, I saw it move. I began to think it probable
that the posterior roots of the spinal nerves might have different functions
from the anterior roots. It naturally occurred to the mind to cut the anterior
roots, leaving the posterior untouched. As in the preceding experiment, I made
the section on one side only, in order to have a point of comparison. The
member was completely immovable and flaccid, at the same time preserving its
sensitivity. Finally, that nothing might be neglected, I cut the anterior and
posterior roots at the same time. There ensued absolute loss both of
sensibility and of motion." (Magendie, 1822)
Marie-Jean-Pierre Flourens (French anatomist:
1794-1867): [Selected Internet biography] Was very critical
of phrenology, arguing that it was not possible to localise
brain function too precisely because many of its functions were complex and
all-embracing. Flourens' position comes out well in
the following quotation:
"Each part of the nervous
system [] has a proper function; and that is what makes it a distinct part: but
the activity of each of these parts affects the activities of all the others;
and that is what makes them parts of a particular system. [What matters] is the
way each distinct part of this system contributes to the common activity."
(Flourens, 1824)
Modern neuropsychology is still vigorously debating
this very issue, which remains to be resolved. Flourens
also located the respiratory centres of the medulla
and demonstrated by inflicting cerebellar lesions
upon dogs that the cerebellum was involved in muscular control. His method is
illustrated in the following quotation:
"I made a lesion in the
cerebellum of a young and healthy dog by means of incisions which extended
deeper and deeper. The animal gradually lost the power of ordered and regular
movement, and when the mid-region of the cerebellum was reached he could only
totter along with a zigzag motion. [] The animal was in full possession of his
intellectual facilities and his senses and there was no trace of convulsion; he
was merely deprived of the power to control and regulate his movements. When I
extended the lesion to the innermost layer of the cerebellum the animal lost
the power of motion and of equilibrium completely." (Ibid.)
Flourens also helped shape
our opinions on the relationship between the mind and the body. Consider:
"The function of the
cerebral lobes is to will, to judge, to remember, to see,
to hear, or - in a word - to feel. [They] wish and feel;
that is their proper action. The suppression of these lobes weakens the
activity of the entire nervous system." (Flourens,
1824; in Herrnstein and Boring, 1965, p221; italics
original)
Jean-Baptiste Bouillaud (1796-1881) [WhoNamedIt Biography
]: In 1825 gave an early description of a motor aphasia [Neuropsychology Glossary], thus:"It is evident that the
movements of the organs of speech must have a special centre in the brain,
because speech can be completely lost in individuals who present no other signs
of paralysis. [From these observations I believe] that the principal lawgiver
of speech is to be found in the anterior lobes of the brain." (Bouillaud, 1825; cited in Head, 1926, p15.)
Despite having a background in phrenology, Bouillaud's methods and conclusions were generally sound.
Nobele: In 1835 reported
on the attempted suicide by gunshot wound to the head of a psychotic patient.
The patient survived, but, perhaps anticipating the work on prefrontal lobotomy
by Moniz a hundred years later, was apparently cured of his mental illness.
Marc Dax (French
physician): In 1836 was one of the first to record that when a stroke paralysed the right side of a right-handed person, the
patient usually suffered speech loss as well. Thus:
"It was known from
anatomic dissection that the nervous pathways of the left hemisphere cross over
in the brain stem and pass on to the muscles in the right side of the body.
From this Dax reasoned that the speech centre must
lie in the left hemisphere." (Gray, 1948, p5.)
Dax's paper, sadly, was
not properly published until 1865, when its impact was dwarfed by the
controversy over Broca's (1861) report (see below).
Richard Owen (British Anatomist:
1804-1892): In May 1837 presented a series of seven lectures on comparative
anatomy to the Royal College of Surgeons. Topics included embryology and
comparative neuroanatomy.
Jules Baillarger (French
neurologist: 1809-1890): In 1840 published investigations of the layered nature
of the cerebral cortex.
Jacques Lordat (French army
surgeon: 1773-1870): In 1843 described a priest who became aphasic after a
stroke. Consider the following account by
"At first he showed an
almost complete motor aphasia but steadily improved until he reached a static
condition in which he could say hardly a word in French but could express
himself fluently in his native provincial dialect of
Lordat also coined the
term paramnesia to describe partial, as
opposed to total, memory recall problems. Lecours, Nespoulos, and Pioger (1987) rate
Lordat's contribution to aphasiology
and neuropsychology very highly, especially insofar as he points to what we
nowadays would call "processing stages".
Henry J. Bigelow (American physician:
1818-1890): Reported in 1850 on the case of a 25 year old railroad worker named
Phineas P. Gage, the victim of a blasting
accident in 1848 which had driven a four-foot long iron bar in through his left
cheek and out through the top of his skull. The injury destroyed much of the
left frontal lobe, together with the medial elements of the right. Nevertheless
it did not prevent the victim walking part of the way to the surgery, nor his
survival for another twenty years. What was equally noteworthy were the changes
to the man's personality which resulted. Whilst his general intellectual level
remained more or less unaffected, his injury changed him from a well-respected
and competent foreman to a state of indifference, carelessness, and frequent
profanity. [The Phineas Gage case turned out to be
one of the classics of the neuropsychological literature. To see how it fits
into modern interpretations of frontal lobe function, see our e-paper on "From Frontal Lobe Syndrome to Dysexecutive Syndrome".]
Guillaume Duchenne (French physician:
1806-1875): In the period 1855-1875, documented a variety of neuromuscular
deficits, including poliomyelitis and progressive atrophy.
2 - Neuroscience 1861-1926
The
following contributions to neuroscience were made following an initial impetus
given by Broca (1861), who showed that localisation of brain function could be successfully
investigated scientifically. Considerable progress at localisation
was made for a few years (say until Ferrier, 1876), but then gradually bogged
down. There were two reasons for this loss of impetus. The first barrier was
that the imaging techniques were technologically poor. The second barrier was
the sheer complexity of the NS. Many of the most important functions (like
memory, for example) seemed to be literally unlocatable.
The first barrier began to lift in 1926, when Berger developed the EEG as a
non-invasive imaging technique. The second is with us still. The workers to
note are:
Pierre-Paul Broca (French physician:
1824-1880) In 1861, in one of the top ten most influential scientific reports
of that century, described the autopsy of a brain tumour
patient named Leborgne. Prior to his death, Leborgne had displayed a reasonably intact understanding of
the world, including the ability to respond appropriately to both written and
spoken instructions. Despite being able to understand speech, however,
his ability to produce it was grossly impaired, although even then it
was necessary to differentiate the voluntary production of speech (which was
non-existent) from the production of emotional and/or overlearned
utterances (curses, expletives, rhymes, days of the week, etc.) which was
intact. Having seen similar cases before where there had been damage to the
lower regions of the left frontal lobe, Broca
predicted that Leborgne's autopsy would reveal a
similarly located lesion, and this prediction was duly borne out. Leborgne died on 17th April 1861, and Broca
reported the results of the autopsy to the Societe d'Anthropologie (of which he was secretary) the very next
day. Leborgne's tumour, the
size of a hen's egg, was centred on the posterior
third of the left inferior frontal gyrus, the area
known to this day as "Broca's Area". Broca called the deficit aphemia.
Broca should also be credited with introducing the
term limbic lobe in 1878. He used this term to refer to the oldest areas
of the telencephalon, ie.
those anatomically closest to the diencephalon.
Armand Trousseau (French physician:
1801-1867): In 1864 substituted the term aphasia [Neuropsychology Glossary] for aphemia.
(Head, 1926, laments this unnecessary interference, and credits Trousseau with
having added nothing else deserving to be remembered; and since Lecours, Nespoulos, and Pioger, 1987, tell us that Trousseau's treatment of
aphasics included applying leeches around the anus, Head might well have been
right.)
Otto Deiters (German anatomist:
1834-1863): In 1865 sketched the first reasonably accurate diagrams of the
neuron.
Theodor Meynert (Austrian
physician: 1833-1892): Meynert (1867) is credited by
Freud (1891) with having played an important part in shaping the turn-of-century
understanding of brain function, especially the model of an all-powerful
cortex, divided into many projection areas, and presiding over a variety of
ascending and descending fibre tracts. The fact that
this model remains the standard more than a century after Freud makes this
tribute doubly deserved.
Henry Charlton Bastian (British physician): In 1869
claimed (a) that we think in words, and thus (b) that if the auditory
comprehension centres are damaged, the faculty of
thought will be degraded as well. Also produced an early flow diagram showing
the language centres and the communication routes
between them.
J.W. Ogle: In 1869 coined
the term agraphia to apply to acquired
disorders of writing, although it was not until Exner
(1881) that the brain area responsible was identified.
Gustave Fritsch (1838-1927) and Julius
Hitzig (1838-1907) (Prussian army surgeons):
Immediately after the Battle of Sedan (Franco-Prussian War, 1870), they toured
the battlefield looking for head-injuries among the casualties. They carried a
portable generator which they then used to apply electrical stimulation to the
exposed brain tissue. Their observations of the resulting muscle twitchings helped them locate the motor part of the cortex.
They found that limb movements could be induced by stimulating small areas of
brain and that the mapping of cerebrum to limb was very specific and reliable.
Silas Weir Mitchell (American army surgeon:
1829-1914): Did much the same as Fritsch and Hitzig,
but using American battle injuries during the American Civil War. In 1872 he
published his findings in Injuries of Nerves and their Consequences.
Vladimir Betz (Russian anatomist:
1834-1894): In 1874 published his description of the pyramidal cells in
the motor area, later to become known as the great cells of Betz.
Robert Bartholow (American
neurologist): According to Penfield and Boldrey
(1937) was the first (in 1874) to directly stimulate the human cortex
electrically. Applied a faradic (AC) current to the exposed dura
of patient Mary, a 30 year old domestic, producing contralateral
muscle twitchings and hallucinatory sensations, and
thus initiating the major experimental tradition subsequently carried through
by the likes of Ferrier, Cushing, and Penfield.
Carl Wernicke (German physician:
1848-1905): In Wernicke
(1874) he described the "opposite" syndrome to Broca's,
that is to say one in which verbal comprehension was severely impaired but the
ability to produce speech was intact. Patients with Wernicke's
aphasia [Neuropsychology Glossary] were found to have left
hemisphere lesions affecting the first temporal convolution (at the junction of
the left temporal and parietal lobes), far enough away from the primary
auditory area, therefore, for hearing per se to be intact. Wernicke
accordingly placed auditory comprehension in this area, and held it to be the
store of "sound images" (Klangbilder),
the basis of understanding spoken words. Wernicke's
aphasia is readily demonstrated in such patients by asking them verbally to
perform a target task, the request falling not upon deaf ears, but upon a brain
which simply cannot decode the incoming message. Wernicke
was subsequently criticised by Freud (1891) and Head
(1926) for being too ready to rely on simplistic diagrammatic explanations of
language difficulties.
John Hughlings Jackson (British
physician: 1835-1911): Lectured and wrote on aphasiology
in the period from 1864, taking a strong stand against the wave of "localisationists". Like Flourens
before him he argued that localisation successes were
of restricted value because of the complex nature of the system being
investigated.
"To locate the damage
which destroys speech and to localise speech [itself]
are two different things." (Jackson, 1864; cited in Head, 1926, p50; emphasis added.)
"Emotion uses
propositions in a largely interjectional manner, that is to say, reduces them
to or towards inferior speech. Emotion, as it were, appropriates and subordinates
an intellectual utterance." (Jackson, 1864; cited in Head, 1926, p38; emphasis added.)
"Loss of speech is,
therefore, the loss of power to propositionise."
(Ibid, p41; emphasis added.)
The topic of propositional speech lay dormant for many
years, but has recently re-emerged in modern cognitive science, where it is
used to distinguish propositional knowledge [Memory Glossary] from procedural knowledge as
part of the study of epistemology (ie. the science of
knowledge itself). This resurrection of what is essentially a philosophical
debate has been prompted by computer science's ongoing drive towards
intelligent computers.
William Hammond (American Surgeon-General:
1828-1900): In 1871 published the first American textbook of neurology drawing
upon his experiences organising treatment for head
injuries during the American Civil War. In this textbook, he coined the term athetosis to describe a condition where there was an
inability to retain the fingers/toes in a fixed position. Instead there was an
uncontrollable state of continuous motion, which he tentatively attributed to
basal ganglia lesions.
Richard Caton (British
physiologist): In 1875 was the first to demonstrate that the brain produced
electric currents detectable by a scalp-surface electrode. Although this
predated Berger's (1926) development of a working EEG by some 50 years, Caton was unable to make much progress because the
electrical signals involved were too small to be detected by the monitoring
equipment available at the time.
Sir David Ferrier (British physiologist:
1843-1928): Published several papers in the period 1872-1876, culminating in The
Functions of the Brain in 1876. In these he reviewed earlier findings and
added clinical and experimental evidence of his own which he used to map the
functions of the cerebral hemispheres. Unlike Fritsch and Hitzig
he applied a "Faradic" as opposed to a "Galvanic" electrode
voltage (i.e. AC rather than DC). His experimental subjects included a variety
of animals - birds, frogs, fishes, and mammals - and he found, for example,
that an electrode applied to the auditory cortex of a monkey's brain would
cause the contralateral ear to be pricked
up, accompanied by head turning to that side.
Adolph Kussmaul (German physician:
1822-1902): Suggested in 1877 that verbal expression goes through three stages,
namely preparation, internal diction, and articulation (compare Lordat, 1843). Kussmaul also
proposed the terms (a) agrammatism for
disorders of word order, and (b) pure word deafness for the (rare)
syndrome where the patient is unable to understand the spoken word but has
intact reading comprehension and speech (for more on which see Auerbach, Allard, Naeser,
Alexander, and Albert, 1982, if interested). Another who recognised
the true complexity of the underlying system, and thus the inherent futility of
simplistic localisation models. Thus:
"We turn away with a
smile from all those naive attempts to seek a 'seat of speech' in this or that
cerebral convolution." (Kussmaul, 1877; cited in
Head, 1926, p64.)
Ernst Haeckel (German zoologist:
1834-1919): Suggested in 1866 that "ontogeny recapitulates phylogeny",
that is to say, that the developing embryo passes through the same stages in
days and hours that the mother species did as it evolved in geological time.
Camillo Golgi (Italian
histologist: 1843-1926): In 1878 perfected the Golgi stain, a technique
of staining neural tissue so that individual neurons would stand out better
under the microscope.
Sir William Broadbent (British physician:
1835-1907): In 1878 gave one of the first accounts of "jargoning"
aphasia, and postulated auditory and motor speech centres
united by a commissure. Also separated naming and propositionising as higher cognitive functions (because he
had observed patients who could quite happily have ideas, but could not name
the objects in those ideas correctly).
Siegmund Exner (Austrian physiologist: 1846-1926): In 1881
identified Exner's area, a secondary
motor area situated at the foot of the second frontal convolution (just above Broca's area), which he claimed helped organise
the motor behaviour necessary for fluent writing.
Damage to this area induces the agraphia described
earlier by Ogle (1869).
J.B. Charcot (French physician:
1825-1893): In 1883 published a diagram of the language centres
known as "Charcot's bell". In 1887 went on to propose that a word has
four fundamental elements: an auditory image, a visual image, and two motor
images, one articulatory and one graphic. Like Wernicke before him and Lichtheim
after him, he saw these as being subject to damage individually or in various
permutations, each with characteristic results.
Ludwig Lichtheim (German physician:
1845-1928): In 1885 added to the aphasia-localisation
debate by drawing a set of explanatory diagrams showing how the language centres as he saw them were connected up. These diagrams
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 concept centre (the "B" centre - from the German word Begriffe) took care of the semantic element of the
equation. The beauty of the resulting diagram - affectionately known as "Lichtheim's house" and shown at Figure
3.6 - is that a different aphasic syndrome naturally follows damage to any
single pathway or any single centre (compare Charcot above). Lichtheim was also one of the first to recognise
the diffuseness of higher-order cognitions (or what we today term the
"semantic system" or the "central executive"). In his
Figure 7, he placed these in a set of distributed "conceptual centres". His work was subsequently described by Head
(1926 - see below) as being "the high-water mark" of the
diagram-making approach to language localisation.
H. Grashey (German neurologist): In 1885 added to the
modularity of processing debate with a diagram more complex than those of
Charcot or Lichtheim.
Sergei Korsakoff (Russian
neurologist: 1853-1900): In 1887 described a neuropathic disorder associated
with severe confusional state and anterograde
amnesia, yet with preserved consciousness and general intellectual capacity.
Sigmund Freud (Austrian physician:
1856-1939): Long before he achieved fame with his theory of psychoanalysis,
Freud was a competent neuropsychologist, having published an influential
monograph on aphasia in 1891. Consider:
"Freud's monograph on
aphasia [] is an incisive analysis of the so-called diagram-makers, those aphasiologists who would reduce brain and language to
simple schemes of circumscribed cortical centres
linked by unidirectional subcortical pathways. Chief
architects of the diagram-maker school were Wernicke
and Lichtheim, and their formulations of conduction
aphasia and the transcortical aphasias were
particular targets of Freud's trenchant criticism." (Henderson, 1992, p19.)
The monograph includes a penetrating analysis of the
neuropsychology of semantics - that is to say, of the relationship between a
word and its referent, and generally has much in common with modern transcoding models.
Gottlieb Burckhardt (Swiss neurologist:
1836-1907): In 1891 reported six cases of unilateral frontal lesions carried out
in the period from 1888 to alleviate psychiatric rather than organic disease.
Became thereby "the first modern psychosurgeon" (Whitaker, Stemmer,
and Joanette, 1996).
Friedrich Goltz (German
physiologist: 1834-1902): In 1892 noted that decorticate dogs could be aroused
to "sham" rage by the most trivial stimuli. Nor (cited in Blakemore,
1977) do they have experiences "for only he who has memories can have
experiences".
Pierre Marie (French physician): In 1906
coined the term anarthria to describe articulatory disorders not resulting from a defect of the
articulators themselves. Also scathingly criticised diagram-making
- the tendency to propose precisely localised
cortical lesions to explain aphasic deficits.
Georg Elias Müller (German
psychologist: 1850-1934): [Optionally Mueller or Muller.] [Selected Internet biography] In 1900, in
cooperation with Pilzecker, developed the consolidation
theory of memory. This postulates an electrically based short term memory
(see both Lorente de No and Hebb
below) which gradually consolidates itself into a structurally based long term
memory.
Hugo Liepmann (German physician:
1863-1925): In 1900 and 1905 described the defect known as apraxia
.....:
"This he defined as
inability to act or to move various parts of the body in a purposeful manner,
although the power of movement is intact. There is no paralysis and the patient
understands what is required of him; yet he cannot execute the action he wishes
to perform. The apraxic possesses a sufficient sensori-motor apparatus, but he cannot employ it at will in
certain directions....." (Head, 1926, p94.)
Sir Charles Sherrington (British physiologist:
1857-1952): Studied the spinal cord and its reflexes. Published The Integrative
Action of the Nervous System in 1906 in which were contained many useful
concepts, for example that of the final common pathway.
Sir Victor Horsley (British physician:
1857-1916): Pioneered neurosurgery in May 1886. In 1909, developed the stereotaxic frame, a contraption fitted externally to the
head to allow needle electrodes to be guided very precisely in through the
skull. This technique allowed mapping of very small subcortical
structures such as the thalamic and hypothalamic nuclei.
Korbinian Brodmann (German neurologist: 1868-1918): Departed from the
traditional "naked eye" description of the brain, and turned instead
to microscopic considerations as a basis for cortical mapping. Found under the
microscope that the cerebral cortex contains six distinct layers (or "laminae"). Also that in different areas of the cortex
the relative predominance of each layer is different, reflecting the different
nature of the neural processing required. Brodmann
allocated numbers to these different areas, and his numbering schema is still
in use (Brodmann, 1909).
Harvey Cushing (American neurosurgeon:
1869-1939): In 1909 performed the first open-skull cortical stimulation on
conscious humans, a method later popularised by
Penfield.
K. Kleist (German psychiatrist): In 1912 described the
deficit of constructional apraxia, in which
the ability to organise actions in space is affected.
He regarded this as another disconnection syndrome; a loss of the
ability to transmit information between the processes of spatial analysis and
those of voluntary action. (There are various tests of constructional apraxia nowadays, for details of which see McCarthy and
Warrington, 1990, pp107-109.) (See also separate
entry for 1934.)
Von Monokow (Russian
physiologist): In 1914 resurrected
Gordon Morgan Holmes (1876-1965) (Irish
neurologist): In 1917 studied the behaviour of war
wounded, focusing on lesions of the cerebellum. Coined the term
"decomposition" to describe the resulting inability to control more
than one joint at a time.
Henry Head (British physician):
Investigated the role of the thalamus in emotional behaviour
and consciousness. Wrote extensively on aphasia, including the 1926 classic
text Aphasia and Kindred Disorders of Speech, and recognised
the importance of the brain as a representational system, coining the term schema
to refer to the end-result of perceptual abstraction. Here are some of his
major points:
"The processes which
underlie an act of speech run through the nervous system like a prairie fire
from bush to bush; remove all inflammable material at any one point and the
fire stops. So, when a break occurs in the functional chain, orderly speech
becomes impossible, because the basic physiological processes which subserve it have been disturbed." (Head, 1926, p474; emphasis added.)
"The site of such a
breach of continuity is not a 'centre for speech', but solely a place where it
can be interrupted or changed." (Ibid, p474;
emphasis added.)
"There are no centres for speaking, reading, writing or other forms of behaviour comprised in the normal use of language. On the
other hand, there are areas of the brain within which structural injury can
produce disorders of symbolic formulation and expression." (Ibid, p478.)
"Cortical and subcortical mechanisms participate in every act of
language. The deeper a lesion extends from the surface into the substance of
the brain, the more definite and permanent will be the disorders of
speech." (Ibid, p478.)
3 - Neuroscience From 1926
We
break at 1926 for two reasons. Firstly, as just noted, it was the year of
Head's monograph on Aphasia, and secondly, as we now note, it was the birthyear of the first modern scanning techniques .....
Hans Berger (German psychiatrist:
1873-1941): In 1926, following experiments carried out on his young son, Klaus,
perfected pen-tracing machinery sensitive enough (a) to detect, and (b) to
display, brainwaves from the surface of the scalp (that is to say, non-invasively).
Here was the first technique of measuring brain activity in normal subjects. (NB:
Berger's technique was a major methodological milestone in the neurosciences.)
Walter Cannon: In 1927 expounded the
"thalamic theory" of the emotions. This proposed that emotional feeling
is the result of stimulation of the dorsal thalamus, whereas emotional expression
results from activity of the hypothalamus. One key prior observation was that
"sham" behaviour could be elicited in decerebrated animals, but only if the thalamus remained
intact. Cannon also coined the term homeostasis to describe the
processes maintaining the body's internal environment in a stable state.
C.U. Äriens Kappers (Dutch comparative
anatomist): In 1929 published The Evolution of the Nervous System in
Invertebrates, Vertebrates, and Man, one of the classics of comparative neuroanatomy. Also reviewed various earlier methods of
calculating the "cephalisation coefficient"
J.W. Papez (American neuroanatomist:
1883-1958): In 1937 named the limbic system, comprising Broca's (1878) limbic lobe, plus elements of the
diencephalon, as the centre of motor and emotional behaviour.
Karl Lashley (American
neuropsychologist: 1890-1958): In 1929 published Brain Mechanisms and
Intelligence in which he laid out his theory of mass action. This
holds that there is very little localisation of
function in the cerebral cortex, but a lot of generalised,
or "diffuse", neural activity. He gave this principle the name equipotentiality, because it meant that each part of
the brain was equally capable (at birth, at least) of doing any given job.
Lorente de No: Postulated in
1933 that neural reverberatory loops might be able to
function as physiological substrates of the engram (ie. a neural circuit, properly interconnected, would
continue to stimulate itself for a length of time after the disappearance of
the originating stimulus.)
Karl Kleist (German psychiatrist:1879-1960):
[Selected Internet biography] In 1934 published
a detailed analysis of a large sample of head wounds from World War I, and,
contrary to Lashley's cautionary advice, added
further areas to the cortical localisation maps. Kleist's (1934) cortical map remains of considerable value to
this day. McCarthy and
Anokhin (Russian
physiologist): Pursued Jackson's (1864) and Von Monokow's
(1914) arguments as to the complexity of neural coordination, arguing strongly
(1935) that to understand cognition properly you had had to see the brain as a
system.
Egas Moniz (Portuguese
psychiatrist: 1874-1955): In 1935 resurrected and improved Burckhardt's
psychosurgical operations (see Burckhardt's entry for 1891, as well as Chapter
3).
Wilder Penfield (Canadian neurosurgeon:
1891-1976): Continued work with Cushing's open skull stimulation method. In
1937 published a detailed localisation map summarising these findings. This included areas where
electrical stimulation could momentarily induce aphasic signs in previously
normal subjects. Thus one patient, when shown a picture of a foot, could only
answer: "That's what you put in your shoes." When the electrode was
withdrawn, however, the ability to answer "foot" returned
immediately. Another line of investigation concerned the location of episodic
memory. Typical findings here were that electrical stimulation of the temporal
lobe could produce vivid "flashback" memories of past incidents, even
though these had been long forgotten and were, in themselves, usually quite
trivial. What is challenging is that at the age of 84, after decades of
investigation, Penfield (1975) admitted one significant failure in his
searches: "There is no room or place," he concluded, "where
consciousness dwells."
Von Wagenen & Herren (1940)/Akelaitis (1941): First reports of
deliberate section of the corpus callosum to prevent interhemispheric propagation of epileptic seizure.
Bodamer: In 1947 described
patients with disproportionate impairments in recognising
faces as opposed to objects. He termed this defect prosopagnosia,
and saw face recognition as distinct from object recognition because it was
biologically more primitive.
Walter Hess (Swiss physiologist:
1881-1973): Demonstrated in 1949 that specific emotional or instinctive behaviours could be elicited by stimulation of specific subcortical areas. (NB: Hess's technique was a major
methodological milestone in the neurosciences.)
Donald Hebb (Canadian
psychologist): In 1949 published The Organisation
of Behaviour in which he extended Lorente de No's concept of reverberatory
neural circuits and proposed what he termed the cell assembly. This he
saw as a set of neurons which became synaptically
inter-associated as the result of experience, and this, in turn, he saw as the
structural basis of the engram.
Various: Between 1949 and the mid-'fifties, a small
group of researchers, primarily Bernard Katz, Alan Hodgkin, Andrew Huxley, Lord
Adrian, and Herbert Gasser, analysed the microbiology
of neural transmission, and discovered the nature of the resting potential and
the action potential.
David Hubel: In 1957 developed a
microelectrode capable of recording the activity of single neurons from the grey
matter of the cerebral cortex. In cooperation with Torsten
Wiesel, he used this method to analyse the functional
microarchitecture of the visual cortex.
4 - Where To Next?
By
the 1950s, the pace of neuroscientific
discovery was beginning to hot up. For the more recent discoveries we therefore
refer you to a number of separate resources, as follows .....
·
For more on frontal lobe pathology and assessment, see
our e-paper on "From Frontal Lobe Syndrome to Dysexecutive Syndrome".
·
For more on the neuroanatomy
of mathematical cognition, see our e-paper on "The Psychology of Numeracy".
·
For more on the neuroanatomy
of dyslexia, see our e-paper
on "Dyslexia and the Cognitive Science of Reading and Writing".
·
For more on the neuroanatomy
of memory, see our Memory Glossary.
- For more on
the cognitive neuropsychology of communication, see Section 6 of our e-paper on "Speech Errors, Speech Production
Models, and Speech Pathology".
5 - References
See the
Master References List
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