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bioRxiv · 10.1101/2024.12.06.627190

Salience Network Segregation and Symptom Profiles in Psychosis Prodrome Subgroups

Iyer, A.·Stanford, W.·Dayan, E.·Xavier, R. M.
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Abstract

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.

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Iyer, A., Stanford, W., Dayan, E., Xavier, R. M.. 2024-12-12. Salience Network Segregation and Symptom Profiles in Psychosis Prodrome Subgroups. https://doi.org/10.1101/2024.12.06.627190

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