Lee Hadden writes " From Science News, "Scripted Brains: Learning to read evokes hemispheric trade-off." From
childhood through adolescence, the process of learning to read involves an
amplification of specific types of left-brain activity and a dampening of
right-brain responses, a new brain-imaging study finds.
The complexities of pediatric brain imaging have precluded studies
that trace the neural development of cognitive skills acquired during
childhood. Using a task that isolates reading-related brain activity and
minimizes confounding performance effects, we carried out a cross-sectional
functional magnetic resonance imaging (fMRI) study using subjects whose
ages ranged from 6 to 22 years. We found that learning to read is
associated with two patterns of change in brain activity: increased
activity in left-hemisphere middle temporal and inferior frontal gyri and
decreased activity in right inferotemporal cortical areas. Activity in the
left-posterior superior temporal sulcus of the youngest readers was
associated with the maturation of their phonological processing abilities.
These findings inform current reading models and provide strong support for
Orton's 1925 theory of reading development."