Contributions of magnetic source imaging to the understanding of dyslexia.

The problem in dyslexia is difficulty learning how the printed word maps onto spoken language. Magnetic Source Imaging protocols were used in three studies. The first study with dyslexic children showed greater activity in the right temporoparietal region. The second study showed the aberrant neural circuit was present in initial stages of reading acquisition. The third study demonstrated that the aberrant profile could be normalized following intensive instruction. These findings suggest that dyslexia represents a functional deficit in the neural circuit that mediates the conversion of print to sound, which is amenable to change given adequate instruction.