‘Underconnectivity’ is considered one of the best-supported theories for the neural basis of autism. But many questions remain unanswered, says Jon Brock.

Researchers should be cautious about interpreting the results of studies that rely on diffusion tensor imaging, says Carlo Pierpaoli.

To better understand how local connectivity is altered in autism, we first need to define what it means, says Tal Kenet.

A number of studies have found no connectivity differences between people with autism and controls, but few have been published so far, says Dan Kennedy.

Autism may result from reduced anatomical connectivity and functional connectivity between the frontal cortex and more posterior areas of the brain, say Marcel Adam Just and Timothy Keller.

Researchers can use functional magnetic resonance imaging to map fetal brain connectivity during the second and third trimesters of pregnancy, according to a study published 20 February in Science Translational Medicine.

In 2003, John Rubenstein and Michael Merzenich first described the theory, now popular in autism, that the disorder reflects an imbalance between excitation and inhibition in the brain. Takao K. Hensch and Parizad M. Bilimoria review the paper and its impact on the field.

A new map highlighting brain circuits finds that regions involved in synthesizing information tend to vary more among people than those that govern sensory and motor functions.

Connections between neighboring groups of brain cells are weaker in individuals with autism than in controls, according to a report published 14 January in the Proceedings of the National Academy of Sciences.

Mice lacking CDKL5, a gene linked to both Rett syndrome and autism, show features associated with both disorders, according to a study published 26 December in the Proceedings of the National Academy of Sciences.