Beginning in 1825, the French physician Jean–Baptiste Bouillaud (1796–1881) reported series of patients who had lost the ability to speak but understood what was said to them. At autopsy, he described areas of injury within the anterior (frontal) lobes, and Bouillaud proposed that a “special cerebral center…distinct and independent” (p 42) was responsible for speech [6]. This interpretation accorded with Gall’s organ for language sense, which Gall had located within a more delimited portion of the anterior lobes [5].
Building on Bouillaud’s work, Louis Victor Marcé (1828–1864) in 1856 described patients whose speech or writing was impaired; 2 patients wrote well despite speaking poorly [7]. By way of explanation, Marcé proposed that the agent responsible for speech coordination, but not the agent for writing coordination, had been damaged. These cases implied that a brain faculty coordinated the graphic representation of ideas, the formation of letters, and the assembly of letters into syllables and words. The role of this writing faculty was analogous to the speech center described by Bouillaud [6]. Marcé recognized, as had Bouillaud, that speech and writing were usually impaired together after brain injury. He reasoned that the speech and writing faculties were separate but intimately connected, but Marcé did not propose anatomically distinct centers.
1861: Broca’s Aphemia
Bouillaud’s notion of a speech center in the anterior lobes was refined by Broca. In 1861, members of the Anthropological Society of Paris, co-founded by Broca the year before, debated the relation between intelligence and brain size. Noting that the brain is a complex organ, a debate participant – Bouillaud’s son-in-law Ernest Auburtin (1825–1893) – asked whether different parts of the brain should be considered separately. He mentioned a patient who had lost speech but who retained the ability to understand and, further, he predicted that an autopsy would eventually confirm a softening (stroke) within the anterior lobes in accordance with Bouillaud’s ideas [8].
By remarkable coincidence, a man with similar symptoms was admitted to Broca’s surgical service at the Bicêtre hospital 8 days later. Years before, he had lost his ability to speak, and he was paralyzed on his right side. He died of infection shortly thereafter, and Broca reported clinical and autopsy findings to the Anthropological Society [1]. His patient “understood almost all that one said to him” (p 236), and Broca interpreted this finding as evidence that intelligence was spared. The autopsy showed that “the frontal lobe of the left hemisphere was softened in most of its extent,” particularly affecting “the middle part of the frontal lobe of the left hemisphere” (p 237) [1]. This localization, according to Broca, supported Bouillaud’s view that anterior lobes were affected when speech was lost.
Broca used the term aphemia (aphemie) to describe the disorder of articulate language shown by his patient [9]. As more cases of aphemia were reported by Broca and others, he suggested that brain injury causing aphemia consistently affected one region of the anterior lobes (the posterior portion of the third frontal convolution [gyrus]) on one side of the brain (the left side) [10]. Broca noted that the left cerebral hemisphere also controlled movements responsible for right handedness and suggested, by way of analogy, that “we speak with the left hemisphere” (p 384) [11]. It was only several years later that Broca mentioned reading and writing disturbances in relation to aphemia [12].
Alexia and Agraphia in the Wake of Broca’s Discovery
Armand Trousseau (1801–1867) in Paris proposed the term aphasia (aphasie) for Broca’s aphemia [13]. He recognized that deficits in articulate language were almost always accompanied by disturbances in other aspects of intelligence, including the inability to read and write [13, 14]. During the several years after Broca’s formulation of a left hemisphere cortical center for articulate language, other physicians reported cases intended to confirm, refute, or extend Broca’s observations. Key issues were the relation between language and intelligence, whether spoken language could be disturbed without impairing written language or the converse, and whether there were separate cortical centers for writing or reading [10].
Four years after Broca’s first report, Moritz Benedikt (1835–1920) in Vienna used the terms alexia (Alexie) and agraphia (Agraphie) in his review of controversies surrounding aphasia as described by Broca, Trousseau, and others [15]. Two years later in England, William Ogle (1824–1905) published cases of patients with impairments in speech, most with autopsy findings. He emphasized defects in “expression of ideas in written symbols or writing” (p 99), and he provided a classification scheme [16]. Ogle, like Marcé, viewed speech and writing as parallel activities. Brain injury might disrupt articulate speech (aphasia), written communication (agraphia) or, commonly, both. He described 2 varieties of agraphia (amnemonic and atactic agraphia) [16]. Amnemonic agraphia was due to impaired memory for words. A patient with amnemonic agraphia could “form letters and words with sufficient distinctness, but he either substitutes one word for another or … writes a confused series of letters which have apparently no connection to the words intended” (p 99). Atactic agraphia occurred when the patient no longer knew how to write words, and “the power of writing even separate letters is lost” (p 99).
Ogle described a patient who wrote well after a stroke but whose speech production was sharply limited. The autopsy revealed a small area of softening in the posterior part of the left inferior frontal convolution. This location, according to Ogle, strongly supported Broca’s view of the brain area affected in atactic aphasia (Broca’s aphasia). However, because writing was unaffected, Ogle concluded “that the faculty of speech and the faculty of writing are not subserved by one and the same portion of the cerebral substance” (p 106). Still, the hypothesized speech and writing centers must be “closely contiguous” (p 100), since aphasia and agraphia so frequently occurred together [16].
By 1874, it was clear that aphasia was not a homogenous syndrome. This was the year in which Carl Wernicke (1848–1904) in Breslau prepared his famous monograph on the symptom complex of aphasia [17]. Wernicke was the first to offer a plausible anatomical and conceptual framework to accommodate different types of aphasia [18]. He recognized a motor center in the left frontal lobe (Broca’s area) that