Fast word reading in pure alexia: “fast, yet serial”

Abstract

Pure alexia is a severe impairment of word reading in which individuals process letters serially with a pronounced length effect. Yet, there is considerable variation in the performance of alexic readers with generally very slow, but also occasionally fast responses, an observation addressed rarely in previous reports. It has been suggested that "fast" responses in pure alexia reflect residual parallel letter processing or that they may even be subserved by an independent reading system. Four experiments assessed fast and slow reading in a participant (DN) with pure alexia. Two behavioral experiments investigated frequency, neighborhood, and length effects in forced fast reading. Two further experiments measured eye movements when DN was forced to read quickly, or could respond faster because words were easier to process. Taken together, there was little support for the proposal that "qualitatively different" mechanisms or reading strategies underlie both types of responses in DN. Instead, fast responses are argued to be generated by the same serial-reading strategy.

An Eye Movement Study on the Role of the Visual Field Defect in Pure Alexia

“…The stroke in 2000 had caused mild symptoms of aphasia from which, according to his relatives, DN had recovered. He nevertheless produced occasional phonemic and paragrammatic errors as described in a previous study [32]. The hemorrhage from 2007 had resulted in his reading impairment and a left sectoranopia suggesting involvement of the thalamus [33]–[34].…”