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One of the most intriguing characteristics of Williams Syndrome individuals is their hypersociability. The amygdala has been consistently implicated in the etiology of this social profile, particularly given its role in emotional and social behavior. This study examined amygdala volume and symmetry in WS individuals and in age and sex matched controls. Magnetic resonance imaging scans were obtained on a GE 1.5-T magnet with 1.5-mm contiguous slices and were used to measure whole gray matter, white matter and cerebrospinal fluid volumes, as well as amygdala volume (right and left). Results revealed significantly reduced intracranial volume in individuals with WS, compared with controls. There were no differences between groups in absolute amygdalae volume, although there was a relative increase in amygdalae volumes, when adjusted for total intracranial content. There were no inter-hemispheric differences in amygdalae volumes in both groups. These results suggest a relative increase in amygdala volume in WS compared with healthy controls that likely reflects abnormal neurodevelopmental processes of midline brain structures.

Objective-To evaluate volumes and asymmetry of superior temporal gyrus (STG) and correlate these measures with a neurocognitive evaluation of verbal performance in Williams syndrome (WS) and in a typically developing age-matched and sex-matched group.Background-Despite initial claims of language strength in WS, recent studies suggest delayed language milestones. The STG is implicated in linguistic processing and is a highly lateralized brain region.

Background: White matter changes have several histopathologic correlates including cerebral amyloid angiopathy (CAA). The aim of this study was to characterize the clinical, laboratorial and neuroradiological profile of a CAA-related lobar hemorrhages case series. Methods: A cohort of 50 consecutive patients with cerebral lobar hemorrhages was studied and clinical, radiological data and ApoE polymorphisms were analyzed. White matter changes were graded and microbleeds were characterized according to number and location using T₂* MRI. Results: A statistically significant association was found between the prestroke cognitive performance and poststroke dementia and between hemorrhage volume and mortality. More severe white matter changes were found in probable CAA when comparing to possible CAA. The most prominent white matter lesions are associated with the presence and the number of microbleeds. The frequency of APOE υ2 and υ4 alleles was higher in this cohort when compared to a Northern Portuguese population. Conclusion: White matter changes are frequent in lobar hemorrhage patients and are associated with cortical microbleeds, the radiological hallmark of CAA. Therefore, white matter changes may be the sole phenotype of CAA and, potentially, involved in the pre-stroke cognitive impairment presented by the patients, which are genetically distinct from the population in general.

Brain abnormalities in Williams syndrome (WS) have been consistently reported, despite few studies have devoted attention to connectivity between different brain regions in WS. In this study, we evaluated corpus callosum (CC) morphometry: bending angle, length, thickness and curvature of CC using a new shape analysis method in a group of 17 individuals with WS matched with a typically developing group. We used this multimethod approach because we hypothesized that neurodevelopmental abnormalities might result in both volume changes and structure deformation. Overall, we found reduced absolute CC cross-sectional area and volume in WS (mean CC and subsections). In parallel, we observed group differences regarding CC shape and thickness. Specifically, CC of WS is morphologically different, characterized by a larger bending angle and being more curved in the posterior part. Moreover, although CC in WS is shorter, a larger relative thickness of CC was found in all callosal sections. Finally, groups differed regarding the association between CC measures, age, white matter volume and cognitive performance. In conclusions, abnormal patterns of CC morphology and shape may be implicated in WS cognitive and behavioural phenotype.