The New York Times Magazine recently ran a cover article about mapping the connectome, all of the connections that link all of the neurons in someone’s brain. Many of these connections are formed and reinforced as a result of our experiences, and their sum total constitutes everything about our personalities: the memories we’ve formed, the skills we’ve learned, the passions that drive us.
There is even data suggesting that some neurological disorders are in fact “connectopathies,” characterized by either aberrant connections or an unusual extent of connections among neurons. Some studies have found that autism spectrum disorder (ASD) is associated with decreased functional connectivity in the brain, but other experiments have found increased connectivity in autistic brains. A new study may have reconciled these contradictory findings. Researchers at the Weizmann Institute of Science in Israel determined that brain regions with high interconnectivity in controls have reduced connectivity in ASD, and regions with lower connectivity in controls have elevated connectivity in people with ASD.
The scientists analyzed fMRI scans from high functioning autistic adults and controls, obtained from five different data sets. When the scans from the controls were superimposed upon each other, a typical, canonical template of connectivity was clear. Certain regions had high inter hemispheric (between the right and left sides) connectivity: primary sensory-motor regions like the sensorimotor cortex and the occipital cortex. Others showed low interhemispheric connectivity: regions like the frontal cortex and temporal cortex, which are involved in higher order association. Overall, the control brain scans looked pretty much the same as each other.