Henry Charlton Bastian (1837-1915) developed his network model of language processing, modality deficits and correlated lesion localizations in the 1860s and was a leading clinical authority for over four decades. Although his ideas are little referenced today, having been overshadowed by his more eminent Queen Square colleague John Hughlings Jackson, his work on aphasia and paralysis was highly regarded by contemporaries. This paper traces Bastian's lasting but largely unattributed contribution to the development of standardized clinical assessment of language disorders. From 1867 onwards, Bastian trained generations of medical students in neurology. In his 1875 book On Paralysis there is evidence in his case descriptions that Bastian had already implemented a detailed set of procedures for examining aphasic patients. In 1886, Bastian published a 'Schema for the Examination of Aphasic and Amnesic Persons'. Bastian insisted on the utility of this battery for diagnosis, classification and lesion localization; he argued that its consistent use would allow the development of a patient corpus and the comparison of cases from other hospitals. In 1898 his Treatise on Aphasia included a list of 34 questions that were to be used to examine all patients to provide detailed and systematic evidence of spared and impaired abilities in all receptive and expressive modalities. Bastian's contribution to the development of standardized clinical aphasia assessment is reassessed through detailed analysis of his publications and those of his contemporaries as well as new material from archives and casebooks. This evidence demonstrates that his approach to diagnosis of language and other cognitive impairments has propagated through the decades. His legacy can be seen in the approach to standardized aphasia testing developed in the latter 20th century through to today.
Keywords: aphasia; assessment; cognitive neurology; diagnosis; language.