White Matter
White Matter
- Description
White matter refers to the neurons with myelinated axons. Myelination increases transmission speed of action potentials. White matter is involved in both short and long range connections.1
White Matter and ASD
Neuroimaging studies have seen that there are increases in white matter volume in outer zones of the brain, but not inner zones. This suggests that those with ASD have a greater number of short to medium intrahemispheric connections and a lower number of long range interhemispheric connections.2 Both gray and white matter have overall significant growth differences between typically developing children and those with autism, but this may not be indicative of dysfunction because gray and white matter growth tends to differ depending on the brain region and gender.3
Citations
1. Geschwind DH. Advances in autism.Annu Rev Med. 2009;60:367-80. PMID 19630577
2. Raichle ME et. al. A default mode of brain function: a brief history of an evolving idea. Neuroimage. 2007 Oct 1;37(4):1083-90; discussion 1097-9 PMID 17719799
3. 9. Schumann CM et. al. Longitudinal magnetic resonance imaging study of cortical development through early childhood in autism. J Neurosci. 2010 Mar 24;30(12):4419-27. PMID 20335478
