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Reiss, A. L.

Publications and source records attributed to Reiss, A. L..

4 recordsLinked to original sources

Relationship between X chromosome mosaicism, neuroanatomy and cognitive performance in females

Females have two X chromosomes, one of which is inactivated early in development with specific regions and genes escaping inactivation. Thus, X chromosome loss putatively results in decreased dosage of X chromosome escapee and pseudoautosomal genes, impacting downstream pathways. Evidence from Turner syndrome indicates that X chromosome monosomy results in consistent neuroanatomical and cognitive phenotypes. However, it remains unclear whether mosaic karyotypes, with mixed proportions of 45X and 46XX cells, attenuate these phenotypes. We examined whether X chromosome mosaicism is predicted by neuroanatomical and cognitive features. Higher proportion of 46XX cells was significantly predicted by structural properties in somatosensory, motor, visual, and language brain areas, and by performance in visuospatial, fine-motor, and language tasks. Thus, mosaicism partially rescues phenotypes linked to full 45X monosomy and may explain the role of the X chromosome not only across heterogeneous phenotypic expression in females, but also in sex differences observed in neuropsychiatric conditions.

neuroscience↗

Gene dosage effects of 22q11.2 copy number variants on in-vivo measures of white matter axonal density and dispersion

22q11.2 deletion (22qDel) and duplication (22qDup) carriers have an increased risk of neurodevelopmental disorders and exhibit altered brain structure, including white matter microstructure. However, the underlying cellular architecture and age-related changes contributing to these white matter alterations remain poorly understood. Neurite orientation dispersion and density imaging (NODDI) was used on mixed cross-sectional and longitudinal data to examine group differences and age-related trajectories in measures of axonal density (i.e., intracellular volume fraction; ICVF), axonal orientation (orientation dispersion index; ODI) and free water diffusion (isotropic volume fraction; ISO) in 50 22qDel (n scans = 69, mean age = 20.7, age range = 7.4-51.1, 64.0% female) and 24 22qDup (n scans = 34, mean age = 21.6, age range = 8.3-49.4, 54.2% female) carriers, and 890 controls (n scans = 901, mean age = 21.9, age range = 7.8-51.1, 54.5% female). The results showed widespread gene dosage effects, with higher ICVF in 22qDel and lower ICVF in 22qDup compared to controls, and region-specific effects of the 22qDel and 22qDup on ODI and ISO measures. However, 22qDel and 22qDup carriers did not exhibit altered age-related trajectories relative to controls. Observed differences in ICVF suggest higher white matter axonal density in 22qDel and lower axonal density in 22qDup compared to controls. Conversely, differences in ODI are highly localized, indicating region-specific effects on axonal dispersion in white matter. We do not find evidence for altered developmental trajectories of axonal density or dispersion among 22q11.2 CNV carriers, suggesting stable disruptions to neurodevelopmental events before childhood.

neuroscience↗

Finding the neural correlates of collaboration using a three-person fMRI hyperscanning paradigm

Humans have an extraordinary ability to interact and cooperate with others, which plays a pivotal role in societies at large. Despite its potential social and evolutionary significance, research on finding the neural correlates of collaboration has been limited partly due to restrictions on simultaneous neuroimaging of more than one participant (a.k.a. hyperscanning). A series of works now exists that used dyadic fMRI hyperscanning to examine the interaction between two participants. However, to our knowledge, no study to date has aimed at revealing the neural correlates of social interactions using a 3-person (or triadic) fMRI hyperscanning paradigm. Here, for the first time, we simultaneously measured the blood-oxygenation-level-dependent (BOLD) signal of triads (m=12 triads; n=36 participants), while they engaged in a joint drawing task based on the social game of Pictionary(R). General linear model (GLM) analysis revealed increased activation in the brain regions previously linked with the theory of mind (ToM) during the collaborative phase compared to the independent phase of the task. Furthermore, using intersubject brain synchronization (IBS) analysis, we revealed increased synchrony of the right temporo-parietal junction (R TPJ) during the collaborative phase. The increased synchrony in the R TPJ was observed to be positively associated with the overall team performance on the task. In sum, our novel paradigm revealed a vital role of the R TPJ among other ToM regions during a triadic collaborative drawing task.

neuroscience↗