During the latter part of the nineteenth century our description of nerve cell structure underwent a relatively unrecognized, though fundamental, transformation-a quiet revolution of sorts. The central problem facing scientists in neurology (the study of the nervous system) was a related pair: are nerve cells continuous with each other or not, and how is information conducted? Microscope resolution and staining techniques were inadequate at the time to yield definitive proof either way. I contend that explanatory coherence provides a means to (...) elucidate this instance of theory change in the history of science. The means of elucidation will be Thagard's computational model of explanatory coherence, ECHO (). (shrink)