Left- and right-hemisphere forms of phonological alexia

Abstract

We studied the ability of patients with lesions arising from operation for an anterior or posterior (left or right) brain tumour to read a set of words and pronounceable nonwords. In line with previous works, we observed that damage to the left posterior or left anterior cortex can give rise to phonological alexia, where the reading performance of nonwords is affected more than that of words. More surprisingly, similar effects were found in the right posterior group. However, there were significant differences in the error types, for both complex and positional errors, between phonological alexic patients in the three location groups. The findings present difficulties for the position held by theorists of the triangle model that phonological alexia arises from impairments in the language production system or in a general-purpose orthographic–phonological translation system. They also pose new questions about the possible role of the right posterior cortex in letter sequence representation.

Keywords:

• Phonological alexia
• Reading
• Right hemisphere
• Left hemisphere
• Brain tumour

Acknowledgments

We are grateful to the medical and nursing staff of the Neurosurgery Department (Azienda Ospedaliera Universitaria, Udine) for their help. This research was supported by a grant from MIUR (Ministero dell'Istruzione, dell'Universita' e della Ricerca, PRIN 2008J7YFNR004 to T.S.). We would like to thank Brenda Rapp for her detailed comments on earlier drafts of the paper.