Williams Syndrome white matter is wobbly in the same area as that of psychopathy

Medieval illustration of doggie doctor performing analysis on sick blue kitten.

Williams Sydrome is a genetic condition characterized in part by hyper-sociability and heightened anxiety, and a recent report of multimodal imaging points to wobbly white matter connections in the areas where psychopaths also have wobbly white matter connections.

Given that Williams Syndrome,  in terms of personality, is about the polar opposite of psychopathy, what gives?

Jabbi M, Kippenhan JS, Kohn P, Marenco S, Mervis CB, Morris CA, Meyer-Lindenberg A, Berman KF. The Williams syndrome chromosome 7q11.23 hemideletion confers hypersocial, anxious personality coupled with altered insula structure and function. Proc Natl Acad Sci U S A. 2012 Apr 3;109(14):E860-6. Epub 2012 Mar 12. PubMed PMID: 22411788; PubMed Central PMCID: PMC3325656.

Those afflicted with Williams Syndrome* are sometimes described as delightful, playful, caring, musical, talkative, good natured — the polar opposite of the psychopaths we know.  The authors found:

. . .Based on the documented role of the insula in mediating emotional response tendencies and personality, we used multimodal imaging to characterize this region in [Willliams Syndrome individuals] and found convergent anomalies: an overall decrease in dorsal anterior insula (AI) gray-matter volume along with locally increased volume in the right ventral AI; compromised white-matter integrity of the uncinate fasciculus connecting the insula with the amygdala and orbitofrontal cortex; altered regional cerebral blood flow in a pattern reminiscent of the observed gray-matter alterations (i.e., widespread reductions in dorsal AI accompanied by locally increased regional cerebral blood flow in the right ventral AI); and disturbed neurofunctional interactions between the AI and limbic regions. . . .

We would have thought that the uncinate fasciculus would be super-strong in Williams Syndrome — the part connecting emotion and the frontal brain. After all, in psychopaths, this is the white matter fiber that is frayed and pitted. (Here). So we would have thought that Williams Syndrome, characterized in part by gregariousness, would be the opposite. In Williams Syndrome, a different white matter tract is thought to be super dense  (the longititudinal fasciculus), and have other characteristic anatomical gray matter bends and folds.

So this report was surprising to us.

*Williams Syndrome is fully described here, and it is a serious condition for all kinds of reasons.