Editing Paul Broca (section)

=== Broca's area ===
[[File:Pierre Marie, Travaux et memoires. Wellcome L0028667.jpg|thumb|Louis Victor "Tan" Lebourgne's brain (by Pierre Marie)]]
Broca is most well known for his theory that the [[Manner of articulation|speech]] production center of the brain is located on the left side of the brain, and for pinpointing the location to the ventroposterior region of the [[frontal lobe]]s (now known as [[Broca's area]]). He arrived at this discovery by studying the brains of [[aphasia|aphasic]] patients –persons with speech and language disorders resulting from brain injuries.<ref name="Fancher">Fancher, Raymond E. ''Pioneers of Psychology'', 2nd ed. (New York: W.W. Norton & Co., 1990 (1979), pp. 72–93</ref>

This area of study began for Broca with the dispute between the proponents of cerebral localization – whose views derived from the [[phrenology]] of [[Franz Joseph Gall]] – and their opponents led by [[Pierre Flourens]]. Phrenologists believed that the human mind has a set of various [[Faculty psychology|mental faculties]], each one represented in a different area of the brain. In this framework, specific areas may represent personality characteristics like one's aggressiveness or spirituality, or functions like memory and linguistic abilities. Their opponents claimed that Flourens had disproven Gall's hypotheses through careful [[ablation]] – specific and deliberate removal – of brain regions. However, Gall's former student, [[Jean-Baptiste Bouillaud]], kept the localization of function hypothesis alive (especially with regards to a "language center"), although he rejected much of the remaining phrenological thinking. In 1848, Bouillaud relied on his work with patients with brain damage to challenge other professionals to disprove him by finding a case of frontal lobe damage unaccompanied by a disorder of speech.<ref>Schiller, 1979, pp. 172–74</ref> His son-in-law, Ernest Aubertin (1825–1893), began seeking out cases to either support or disprove the theory, and he found several in support of it.<ref name="Fancher" />

Broca's [[Society of Anthropology of Paris]] was a place where language was regularly discussed in the context of race and nationality, and it also became a platform for addressing its physiological aspects. The localization of function controversy became a topic of regular debate when several experts of head and brain anatomy, including Aubertin, joined the society. Most of these experts still supported Flourens' argument, but Aubertin was persistent in presenting new patients to counter their views. However, it was Broca, not Aubertin, who finally put the localization issue to rest.

In 1861, Broca visited a patient in the [[Bicêtre Hospital]] named Louis Victor Leborgne, who had a 21-year progressive loss of speech and paralysis but not a loss of comprehension nor mental function. He was nicknamed "Tan" due to his inability to clearly speak any words other than "tan" (pronounced {{IPA|/tɑ̃/}}, as in the French word {{lang|fr|temps}}, "time").<ref>Paul Broca, « Perte de la parole, ramollissement chronique et destruction partielle du lobe antérieur gauche du cerveau », ''Bulletin de la Société d'anthropologie de Paris'', t. II, séance du 18 avril 1861, [https://books.google.com/books?id=WyYCAAAAYAAJ&pg=PA235 p. 235-238]</ref><ref name=":3">{{Cite news|url=http://www.livescience.com/26599-famous-brain-injury-patient-identified.html|title=Identity of Famous 19th-Century Brain Discovered|newspaper=Live Science|access-date=24 January 2017|archive-url=https://web.archive.org/web/20160614065814/http://blogs.scientificamerican.com/literally-psyched/the-man-who-couldnt-speakand-how-he-revolutionized-psychology/|archive-date=14 June 2016}}</ref><ref name="Fancher" /><ref name="Tan">Broca, Paul. [http://psychclassics.asu.edu/Broca/aphemie-e.htm "Remarks on the Seat of the Faculty of Articulated Language, Following an Observation of Aphemia (Loss of Speech)"] {{webarchive|url=https://web.archive.org/web/20010117173500/http://psychclassics.asu.edu/Broca/aphemie-e.htm |date=17 January 2001 }}. Bulletin de la Société Anatomique, Vol. 6, (1861), 330–357.</ref> Leborgne died several days later due to an uncontrolled infection and resultant gangrene, Broca performed an autopsy, hoping to find a physical explanation for Leborgne's disability.<ref>History of neuroscience: Paul Broca. (9 June 2014). Retrieved from 
https://www.neuroscientificallychallenged.com/blog/history-of-neuroscience-paul-broca</ref> He determined that, as predicted, Leborgne did in fact have a [[lesion]] in the [[frontal lobe]] in one of the [[cerebral hemisphere]]s, which in this case turned out to be the left. From a comparative progression of Leborgne's loss of speech and motor movement, the area of the brain important for speech production was determined to lie within the third convolution of the left frontal lobe, next to the [[lateral sulcus]].<ref>Schiller, 1979, p. 182</ref><ref>Finger, 2000, pp. 142–144</ref> One day after Tan's death Broca presented his findings to the anthropological society.<ref>Finger, 2000, pp. 142</ref>

A second case after Leborgne is what solidified Broca's beliefs that human speech function was localized. Lazare Lelong was an 84-year-old grounds worker who was being treated at Bicêtre for dementia. He had also lost the ability to speak other than five simple, meaningful words – these included his own name, "yes", "no", "always" as well as the number "three".<ref>Schiller, 1979, p. 188</ref> After his death his brain was also autopsied. Broca found a lesion that encompassed much the same area as had been affected in Leborgne's brain. This finding concluded that a specific area controlled one's ability to produce meaningful sounds, and when it is affected, one can lose their capability to communicate.<ref name=":3" /> For the next two years, Broca went on to find autopsy evidence from twelve more cases in support of the localization of articulated language.<ref name="Fancher" /><ref name="Tan" />
[[File:Broca's area animation.gif|thumb|Broca's area]]
Broca published his findings from the autopsies of the twelve patients in his paper "Localization of Speech in the Third Left Frontal Convolution" in 1865. His work inspired others to perform careful autopsies with the aim of linking more brain regions to sensory and motor functions. Although history credits this discovery to Broca, another French neurologist, [[Marc Dax]], had made similar observations a generation earlier. Based on his work with approximately forty patients and subjects from other papers, Dax presented his findings at an 1836 conference of southern France physicians in Montpellier.<ref>Schiller, 1979, p. 193</ref>{{Refn|In his paper "Lesions of the Left Half of the Brain Coincident with the Forgetting of the Signs of Thought", Dax described patients with tumors, strokes as well as sword wounds; no autopsy information was included. Finger, 200, p. 146|group=n}} Dax died soon after this presentation and it was not reported or published until after Broca made his initial findings.<ref name="Finger, 2000, pp. 145-47">Finger, 2000, pp. 145–47</ref> Accordingly, Dax's and Broca's conclusions that the left frontal lobe is essential for producing language are considered to be independent.<ref>Schiller 1979, pp. 192–97</ref><ref name="Finger, 2000, pp. 145-47"/>

However, the brains of Leborgne and Lelong had been preserved whole; Broca had never sliced them to reveal the other damaged structures beneath. Over 100 years later [[Nina Dronkers]], an American [[Cognitive neuroscience|cognitive neuroscientist]], obtained permission to re-examine these brains using modern [[Magnetic resonance imaging|MRI]] technology. This imaging resulted in virtual slices of the historic brains and revealed that these patients had sustained  much more damage to the brain than Broca could have known from just studying the outer surface. Their lesions extended to deeper layers beyond the left frontal lobe, including portions of [[insular cortex]] and critical white matter pathways below the cortex. This work was published in a peer-reviewed article, and has been cited.<ref>{{Cite journal |last1=Dronkers |first1=N. F. |last2=Plaisant |first2=O. |last3=Iba-Zizen |first3=M. T. |last4=Cabanis |first4=E. A. |date=2007-04-02 |title=Paul Broca's historic cases: high resolution MR imaging of the brains of Leborgne and Lelong |journal=Brain |volume=130 |issue=5 |pages=1432–1441 |doi=10.1093/brain/awm042 |pmid=17405763 |issn=0006-8950|doi-access=free }}</ref>

The brains of many of Broca's aphasic patients are still preserved and available for viewing on a limited basis in the special collections of the [[Pierre and Marie Curie University|Pierre-and-Marie-Curie University (UPMC)]] in Paris. The collection was formerly displayed in the [[Musée Dupuytren]]. His collection of casts is in the [[Musée d'Anatomie Delmas-Orfila-Rouvière]]. Broca presented his study on Leborgne in 1861 in the ''Bulletin of the Société Anatomique''.<ref name="Fancher" /><ref name="Tan" />

Patients with damage to Broca's area or to neighboring regions of the left [[Anatomical terms of location|inferior]] frontal lobe are often categorized clinically as having [[Expressive aphasia]] (also known as '''Broca's aphasia'''). This type of aphasia, which often involves impairments in speech output, can be contrasted with [[receptive aphasia]], (also known as '''Wernicke's aphasia'''), named for [[Karl Wernicke]], which is characterized by damage to more [[Anatomical terms of location|posterior]] regions of the left [[temporal lobe]], and is often characterized by impairments in language comprehension.<ref name="Fancher"/><ref name="Tan"/>