Altered Cortical Gyrification in Adults Who Were Born Very Preterm and Its Associations With Cognition and Mental Health

Background: The last trimester of pregnancy is a critical period for the establishment of cortical gyrification, and altered folding patterns have been reported following very preterm birth (\u3c 33 weeks of gestation) in childhood and adolescence. However, research is scant on the persistence of such alterations in adulthood and their associations with cognitive and psychiatric outcomes. Methods: We studied 79 very preterm and 81 age-matched full-term control adults. T1-weighted magnetic resonance images were used to measure a local gyrification index (LGI), indicating the degree of folding across multiple vertices of the reconstructed cortical surface. Group and group-by-sex LGI differences were assessed by means of per-vertex adjustment for cortical thickness and overall intracranial volume. Within-group correlations were also computed between LGI and functional outcomes, including general intelligence (IQ) and psychopathology. Results: Very preterm adults had significantly reduced LGI in extensive cortical regions encompassing the frontal, anterior temporal, and occipitoparietal lobes. Alterations in lateral fronto-temporal-parietal and medial occipitoparietal regions were present in both men and women, although men showed more extensive alterations. In both very preterm and control adults, higher LGI was associated with higher IQ and lower psychopathology scores, with the spatial distribution of these associations substantially differing between the two groups. Conclusions: Very preterm adults’ brains are characterized by significant and widespread local hypogyria, and these alterations might be implicated in cognitive and psychiatric outcomes. Gyrification reflects an early developmental process and provides a fingerprint for very preterm birth

A multimodal imaging study of recognition memory in very preterm born adults

Very preterm (<32 weeks of gestation) birth is associated with structural brain alterationsand memory impairments throughout childhood and adolescence. Here, we used functional MRI(fMRI) to study the neuroanatomy of recognition memory in 49 very preterm-born adults and 50 con-trols (mean age: 30 years) during completion of a task involving visual encoding and recognition ofabstract pictures. T1-weighted and diffusion-weighted images were also collected. Bilateral hippocam-pal volumes were calculated and tractography of the fornix and cingulum was performed and assessedin terms of volume and hindrance modulated orientational anisotropy (HMOA). Online recognitionmemory task performance, assessed with A scores, was poorer in the very preterm compared with thecontrol group. Analysis of fMRI data focused on differences in neural activity between the recognitionand encoding trials. Very preterm born adults showed decreased activation in the right middle frontalgyrus and posterior cingulate cortex/precuneus and increased activation in the left inferior frontalgyrus and bilateral lateral occipital cortex (LOC) compared with controls. Hippocampi, fornix and cin-gulum volume was significantly smaller and fornix HMOA was lower in very preterm adults. Amongall the structural and functional brain metrics that showed statistically significant group differences,LOC activation was the best predictor of online task performance (P 5 0.020). In terms of associationbetween brain function and structure, LOC activation was predicted by fornix HMOA in the pretermgroup only (P 5 0.020). These results suggest that neuroanatomical alterations in very preterm bornindividuals may be underlying their poorer recognition memory performance

Relación entre déficits lingüísticos y atencionales en personas con afasia post-ictus: el papel de la modulación colinérgica

Objetivos: (1) Estudiar la prevalencia de déficits atencionales en personas con afasia crónica post-ictus (PACPI); (2) evaluar si la modulación del sistema colinérgico, con donepecilo, tiene efectos favorables sobre los déficits atencionales y de lenguaje en PACPI; (3) comparar estos efectos con los producidos por la modulación glutamatérgica con memantina; (4) estudiar los correlatos neurales de estas intervenciones. Método: 3 sub-estudios: (1) Comparamos el rendimiento de 55 PACPI con 25 controles sanos en tareas atencionales. (2) Ensayo clínico (20 semanas) aleatorizado, doble ciego y controlado con placebo de 13 PACPI tratados con donepezilo (10mg/día). (3) Ensayo clínico abierto de 10 PACPI tratados con donepezilo (10 mg/día; 8 semanas) y 14 PACPI tratados con memantina (20 mg/día; 16 semanas). Evaluación del lenguaje: Cociente de Afasia de la Western Aphasia Battery, Denominación por Frecuencia de la Evaluación del Procesamiento Psicolingüístico de la Afasia (EPLA 52). Medida de atención: California Computerized Assessment Package (CalCAP). Neuroimagen: 18FDG-PET y RMN funcional con un paradigma de denominación. Resultados (1) Los PACPI tienen peor rendimiento en tareas atencionales (CalCAP; t-test, p<0.05) que los controles. (2) La modulación del sistema colinérgico tiene efectos positivos en medidas de atención, y éstas correlacionan con mejor rendimiento en tareas de denominación (EPLA 52; Pearson's r, p<0.01). 3) Las PACPI que responden al tratamiento con donepecilo mejoran más que las que responden al tratamiento con memantina. La mejoría en denominación correlacionó (Pearson's r, p<0.01) con cambios en el metabolismo (18FDG-PET) y activación (fMRI) de áreas cerebrales inervadas por el sistema colinérgico. Conclusiones (1)Los déficits atencionales son frecuentes entre las PACPI, y éstos se relacionan con peor rendimiento en denominación. (2) El donepecilo tiene efectos positivos sobre los déficits atencionales y de denominación en PACPI.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Frontal networks in adults with autism spectrum disorder.

It has been postulated that autism spectrum disorder is underpinned by an 'atypical connectivity' involving higher-order association brain regions. To test this hypothesis in a large cohort of adults with autism spectrum disorder we compared the white matter networks of 61 adult males with autism spectrum disorder and 61 neurotypical controls, using two complementary approaches to diffusion tensor magnetic resonance imaging. First, we applied tract-based spatial statistics, a 'whole brain' non-hypothesis driven method, to identify differences in white matter networks in adults with autism spectrum disorder. Following this we used a tract-specific analysis, based on tractography, to carry out a more detailed analysis of individual tracts identified by tract-based spatial statistics. Finally, within the autism spectrum disorder group, we studied the relationship between diffusion measures and autistic symptom severity. Tract-based spatial statistics revealed that autism spectrum disorder was associated with significantly reduced fractional anisotropy in regions that included frontal lobe pathways. Tractography analysis of these specific pathways showed increased mean and perpendicular diffusivity, and reduced number of streamlines in the anterior and long segments of the arcuate fasciculus, cingulum and uncinate--predominantly in the left hemisphere. Abnormalities were also evident in the anterior portions of the corpus callosum connecting left and right frontal lobes. The degree of microstructural alteration of the arcuate and uncinate fasciculi was associated with severity of symptoms in language and social reciprocity in childhood. Our results indicated that autism spectrum disorder is a developmental condition associated with abnormal connectivity of the frontal lobes. Furthermore our findings showed that male adults with autism spectrum disorder have regional differences in brain anatomy, which correlate with specific aspects of autistic symptoms. Overall these results suggest that autism spectrum disorder is a condition linked to aberrant developmental trajectories of the frontal networks that persist in adult life

An Open Resource for Non-human Primate Imaging.

Non-human primate neuroimaging is a rapidly growing area of research that promises to transform and scale translational and cross-species comparative neuroscience. Unfortunately, the technological and methodological advances of the past two decades have outpaced the accrual of data, which is particularly challenging given the relatively few centers that have the necessary facilities and capabilities. The PRIMatE Data Exchange (PRIME-DE) addresses this challenge by aggregating independently acquired non-human primate magnetic resonance imaging (MRI) datasets and openly sharing them via the International Neuroimaging Data-sharing Initiative (INDI). Here, we present the rationale, design, and procedures for the PRIME-DE consortium, as well as the initial release, consisting of 25 independent data collections aggregated across 22 sites (total = 217 non-human primates). We also outline the unique pitfalls and challenges that should be considered in the analysis of non-human primate MRI datasets, including providing automated quality assessment of the contributed datasets