Timothy P.L. Roberts1, Sarah Khan1, Michael Rey1, Justin Monroe1, Michael Gandal1, Katelyn Cannon1, John Dell1, Ralph Magee1, J. Christopher Edgar1, Deborah Zarnow1
1Radiology, Children's Hospital of Philadelphia, Philadelphia, PA, USA
DTI measures of white matter anisotropy such as fractional anisotropy (FA) are shown to increase with age (6-18years) in key structures of the auditory pathway, e.g. the acoustic radiations. In the same children, magnetoencephalographic (MEG) recordings of auditory evoked field components in response to auditory stimulation revealed an age dependence of response latency (shortening with increasing age). FA correlated negatively with response latency, providing a structural basis for the electrophysiological finding. A biophysical explanation is proposed based on increasing conduction velocity with increasing maturation, leading to shortened cortical evoked response latencies.