Brain activation during reading in deep dyslexia: An MEG study

Matti Laine, Riitta Salmelin, Päivi Helenius, Reijo Marttila

Research output: Contribution to journalArticleScientificpeer-review

22 Downloads (Pure)


Magnetoencephalographic (MEG) changes in cortical activity were studied in a chronic Finnish-speaking deep dyslexic patient during single-word and sentence reading. It has been hypothesized that in deep dyslexia, written word recognition and its lexical-semantic analysis are subserved by the intact right hemisphere. However, in our patient, as well as in most nonimpaired readers, lexical-semantic processing as measured by sentence-final semantic-incongruency detection was related to the left superior-temporal cortex activation. Activations around this same cortical area could be identified in single-word reading as well. Another factor relevant to deep dyslexic reading, the morphological complexity of the presented words, was also studied. The effect of morphology was observed only during the preparation for oral output. By performing repeated recordings 1 year apart, we were able to document significant variability in both the spontaneous activity and the evoked responses in the lesioned left hemisphere even though at the behavioural level, the patient's performance was stable. The observed variability emphasizes the importance of estimating consistency of brain activity both within and between measurements in brain-damaged individuals.
Original languageEnglish
Pages (from-to)622-634
Number of pages13
JournalJournal of Cognitive Neuroscience
Issue number4
Publication statusPublished - 2000
MoE publication typeA1 Journal article-refereed


  • magnetoencephalography, cortical activation, dyslexia


Dive into the research topics of 'Brain activation during reading in deep dyslexia: An MEG study'. Together they form a unique fingerprint.

Cite this