...she urges scientists to "break out of the sex hormone straightjacket" and to look at steroids as just one of a number of components that are important to the creation of sex and gender, including ...environment and experience.4 Scholars also point to an inextricable link between the chemical operation of hormones and the social process of constructing meaning, both at the level of social interaction and macrocultural constructions of sex categories and gender ideologies.5 While brain organization/activation theory attributes sex and gender differences to hormonal interactions within the developing brain, Fausto-Sterling questions the distinction between activation and organization by pointing out how "the brain can respond to hormonal stimuli with anatomical changes...hormonal systems, after all, respond exquisitely to experience, be it in the form of nutrition, stress, or sexual activity (to name but a few possibilities).
22q11.2 deletion syndrome (22q11DS) is the most frequently occurring microdeletion in humans. It is associated with a significant impact on brain structure, including prominent reductions in gray ...matter volume (GMV), and neuropsychiatric manifestations, including cognitive impairment and psychosis. It is unclear whether GMV alterations in 22q11DS occur according to distinct structural patterns. Then, 783 participants (470 with 22q11DS: 51% females, mean age SD 18.2 9.2; and 313 typically developing TD controls: 46% females, mean age 18.0 8.6) from 13 datasets were included in the present study. We segmented structural T1‐weighted brain MRI scans and extracted GMV images, which were then utilized in a novel source‐based morphometry (SBM) pipeline (SS‐Detect) to generate structural brain patterns (SBPs) that capture co‐varying GMV. We investigated the impact of the 22q11.2 deletion, deletion size, intelligence quotient, and psychosis on the SBPs. Seventeen GMV‐SBPs were derived, which provided spatial patterns of GMV covariance associated with a quantitative metric (i.e., loading score) for analysis. Patterns of topographically widespread differences in GMV covariance, including the cerebellum, discriminated individuals with 22q11DS from healthy controls. The spatial extents of the SBPs that revealed disparities between individuals with 22q11DS and controls were consistent with the findings of the univariate voxel‐based morphometry analysis. Larger deletion size was associated with significantly lower GMV in frontal and occipital SBPs; however, history of psychosis did not show a strong relationship with these covariance patterns. 22q11DS is associated with distinct structural abnormalities captured by topographical GMV covariance patterns that include the cerebellum. Findings indicate that structural anomalies in 22q11DS manifest in a nonrandom manner and in distinct covarying anatomical patterns, rather than a diffuse global process. These SBP abnormalities converge with previously reported cortical surface area abnormalities, suggesting disturbances of early neurodevelopment as the most likely underlying mechanism.
Using a novel source‐based morphometry method called SS‐Detect, we identified 12 structural brain patterns (SBPs) that discriminated individuals with 22q11.2 deletion syndrome from healthy controls. We further demonstrated that deletion size was related to structural covariance patterns; however, history of psychosis did not show a strong relationship with these covariance patterns.
Book Reviews Griffin, Colin; Bassett, Roberta Malee; Hunt, Cheryl ...
International Journal of Lifelong Education,
20/5/1/, Letnik:
27, Številka:
3
Book Review
Book Reviews Griffin, Colin; Bassett, Roberta Malee; Hunt, Cheryl ...
International Journal of Lifelong Education,
05/2008, Letnik:
27, Številka:
3
Book Review
