Atypical cerebral lateralisation in adults with compensated developmental dyslexia demonstrated using functional transcranial Doppler ultrasound.
Functional transcranial Doppler ultrasound (fTCD) is a relatively new and non-invasive technique that assesses cerebral lateralisation through measurements of blood flow velocity in the middle cerebral arteries. In this study fTCD was used to compare functional asymmetry during a word generation task between a group of 30 dyslexic adults and a group of 30 non-dyslexic individuals. In light of previous evidence of atypical laterality in dyslexia, a reduced leftward asymmetry was predicted and confirmed. We know from previous research that most people with atypical language lateralisation have normal language and literacy skills: nevertheless, our results confirm that language laterality is reduced in those with dyslexia. Theoretical explanations for this apparent conundrum are discussed.
Illingworth
Sarah
S
University of Oxford, Department of Experimental Psychology, OX1 3UD, United Kingdom.
Bishop
Dorothy V M
DV
D000328:Adult; D001783:Blood Flow Velocity; D002540:Cerebral Cortex / Q000000981:diagnostic imaging / Q000503:physiopathology*; D002560:Cerebrovascular Circulation / Q000502:physiology; D004410:Dyslexia / Q000000981:diagnostic imaging / Q000503:physiopathology*; D005260:Female; D007839:Functional Laterality / Q000502:physiology*; D006801:Humans; D007807:Language Tests; D008297:Male; D011597:Psychomotor Performance / Q000502:physiology; D017585:Ultrasonography, Doppler, Transcranial; D014705:Verbal Behavior / Q000502:physiology; D014796:Visual Perception / Q000502:physiology; D014825:Vocabulary