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Stanford, W.

Publications and source records attributed to Stanford, W..

2 recordsLinked to original sources

Salience Network Segregation and Symptom Profiles in Psychosis Prodrome Subgroups

BackgroundUnderstanding neurobiological similarities between individuals with prodromal psychosis symptoms can improve early identification and intervention strategies. Here, we aimed to (i) identify neurobiologically similar groups by integrating resting-state functional connectivity and prodromal symptom data and (ii) discern discriminating symptom profiles and brain connectivity patterns in the identified sub-groups. MethodsOur sample (N=922) was extracted from the Philadelphia Neurodevelopmental Cohort and included individuals ages 12-21 years with fMRI and self-reported psychopathology data. Analyses were conducted separately for youth and early adults. We first constructed a two-layer network using pair-wise similarity distances between participants based on resting-state functional connectivity and prodromal positive psychosis symptoms. We then performed community detection via a multiplex stochastic block model to identify subject clusters. ResultsWe identified 2 blocks or communities for both the youth (n=458 and 179) and early adult (n=173 and 112) groups. Connection parameter estimates of the neuroimaging layer were nearly identical between blocks for both age groups whereas there was significant variation for the symptom layer. Psychopathology symptom and brain system segregation profiles were consistent across age groups. The youth block (n=458) with higher salience network segregation values had higher mean scores for prodromal symptoms. However, the early adult block (n=173) with lower salience network segregation had higher mean prodromal scores. ConclusionsBy integrating global similarities in brain connectivity and prodromal symptoms, we identified distinct subgroups. These groups show differences in symptom profiles and network segregation in youth and early adults, indicating significant variations in developmental paths for psychosis spectrum.

neuroscience↗

Redundancy protects processing speed in healthy individuals with accelerated brain aging

Recent advancements in computational learning techniques have enabled the estimation of brain age (BA) from neuroimaging data. The difference between chronological age (CA) and BA, known as the BA gap, can potentially serve as a biomarker of brain health. Studies, however, have documented low correlations between BA gap and cognition in healthy aging. This suggests that protective mechanisms in the brain may help counter the effect of accelerated brain aging. Here, we investigated whether redundancy in brain networks may protect cognitive function in individuals with accelerated brain aging. First, we employed deep learning to estimate individual brain ages from structural magnetic resonance imaging (MRI). Next, we associated CA, BA, and BA gap, with cognitive measures and network topology derived from diffusion MRI and tractography. We found that CA and BA were both similarly related to cognitive measures and network topology, while BA gap did not show strong relationships in either domain. Despite observing no strong relationships between brain-age gap (BA gap) and demographic variables, cognitive measures, or topological features in healthy aging, individuals with accelerated aging (BA gap+) exhibited lower average degree and redundancy within the dorsal attention network compared to those with delayed aging (BA gap-). Furthermore, redundancy in the dorsal attention network was positively associated with processing speed in BA gap+ individuals. These results indicate a potential neuroprotective role of redundancy in structural brain networks for mitigating the impact of accelerated brain atrophy on cognitive performance in healthy aging.

neuroscience↗