"All Against One?" The Debate on the Value of Single-Case Studies in Cognitive Neuropsychology

Does an observed dissociation in a single patient suffice to rule out a cognitive model that has been confirmed in multiple studies including hundreds of observations? This matter is currently being discussed in the field of cognitive neuropsychology, where prominent researchers have recently questioned the value of single-case studies. Instead, these researchers advocate the case-series approach as the preferred method. The debate concerning the preferred approach to studying patients is linked to two competing models of word processing. The present article summarizes the central points of the debate along with its most prominent protagonists and empirical findings.