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Sisk, L. M.

Publications and source records attributed to Sisk, L. M..

4 recordsLinked to original sources

An Open Test--Retest Dataset of Rapid Myelin Mapping Acquisitions

Myelin supports rapid and efficient neural communication and is implicated in brain development, learning, aging, and neurological disease. Although numerous magnetic resonance imaging (MRI) approaches have been proposed to characterize myelin in vivo, they have rarely been evaluated together within the same participants and across repeated acquisitions. To address these gaps, we introduce the Myelin Imaging Reliability and ReprOducibility Resource (MIRROR), an openly available multimodal test--retest MRI dataset of diffusion MRI (dMRI), inhomogeneous magnetization transfer imaging (ihMT), quantitative susceptibility mapping (QSM), MP2RAGE, T1w/T2w ratio mapping, and transverse relaxometry in 22 healthy adults. We evaluated gray--white matter differentiation, intermetric correspondence, test--retest reliability, and participant specificity across 27 myelin-sensitive metrics. Gray--white matter differentiation was strong for dMRI derivatives, MP2RAGE-derived R1, T1w/T2w, and ihMT, while being substantially weaker for QSM measures. Intermetric spatial correlations were generally strongest within acquisition or modeling families. Test--retest reliability was generally high, particularly for dMRI-derived metrics, but was more variable among QSM-, ihMT-, and R2*-derived measures. Regional spatial profiles were also highly participant-specific, with discriminability approaching its upper bound for most metrics. All imaging data, derived maps, and processing code are openly released. MIRROR provides a benchmark for characterizing the measurement properties and practical tradeoffs of scalable myelin-sensitive MRI methods, supporting principled acquisition selection and accelerating methodological development and validation.

neuroscience↗

White matter reflects the childhood exposome

The childhood environment is critical for brain development. However, most neuroimaging studies examine individual environmental measures (e.g., socioeconomic status) or a limited set of exposures, obscuring how the combination of complex, real-world exposures jointly influence brain development. Here we investigated how white matter shape and tissue properties are linked to the childhood exposome, a multidimensional measure capturing over 300 environmental exposures. Using multi-shell diffusion MRI from 8,183 children (ages 9-10) in the ABCD study, we quantified microstructural and macrostructural properties across 62 person-specific white matter tracts. The exposome showed widespread and highly replicable associations with both white matter microstructure and macrostructure: more advantaged environments were associated with larger tract macrostructure and lower orientation dispersion. Principal component analysis revealed that the dominant axis of exposome-white matter covariation aligns with the cortical sensorimotor-association hierarchy, such that tracts spanning this hierarchy exhibit the strongest associations with the exposome. Multivariate models demonstrated that patterns of white matter features explained 25% of the variance in the exposome in unseen individuals. Notably, white matter-based prediction of cognition was markedly reduced after accounting for the exposome ([~]82% reduction in explained variance), indicating that brain-cognition associations overlap substantially with variance captured by the exposome. These findings generalized to independent data from the Healthy Brain Network (n=869), which differs substantially from ABCD in MRI acquisition, participant selection, and childhood environments. Together, these results suggest that white matter architecture strongly reflects the childhood environment.

neuroscience↗

Corticolimbic structure-function coupling is sensitive to childhood adversity and buffers adversity-related symptoms during development

Childhood adversity is a potent predictor of mental health problems across the lifespan, and a rich cross-species literature implicates stress-sensitive corticolimbic circuits in adversity-related psychopathology. Structure-function coupling (SFC) is a promising multimodal marker that is sensitive to developmental plasticity. While emerging evidence suggests cortical SFC is sensitive to adversity exposure during early childhood, it is unknown how SFC in stress-sensitive corticolimbic circuits links adversity exposure with mental health across development. We examined associations between adversity exposure, transdiagnostic symptomatology, and both amygdala-cortical and hippocampal-cortical SFC across development in a large sample of youth (N = 607, 39% F). Results revealed that adversity exposure moderated age-related change in amygdala-vmPFC SFC (p = .007), such that youth exposed to higher, but not lower, levels of adversity showed an age-related increase in amygdala-vmPFC SFC. Further, amygdala-vmPFC SFC buffered the effect of adversity on internalizing symptoms (p = .012), such that those youth with higher adversity exposure who had stronger amygdala-vmPFC SFC also displayed lower internalizing symptoms. Separately, higher adversity exposure was associated with lower hippocampal-limbic network SFC (p = .037), which moderated the effect of adversity on internalizing symptoms (p = .010). These findings highlight that structural and functional neurodevelopment of amygdala-vmPFC and hippocampal-limbic network connections may adapt in distinct ways to support mental health following adversity, with implications for risk and resilience against internalizing psychopathology. Significance StatementDelineating how childhood adversity alters neurodevelopment is critical to understanding the origins of adversity-related risk for mental health disorders. Here, we leverage a multimodal marker of the correspondence between brain structure and function to test how corticolimbic circuits are jointly shaped by adversity exposure. Results reveal that the structure-function coupling of amygdala-vmPFC and hippocampal-limbic networks is associated with adversity exposure and differentially moderate risk for internalizing psychopathology. These findings suggest key roles for neural stress regulation and memory circuits in adapting to support optimal functioning following adversity exposure, and highlight the concordance of neural structure and function as an important indicator of individual-level risk and resilience.

neuroscience↗

Multivariate links between the developmental timing of adversity exposure and white matter tract integrity in adulthood

Early-life adversity is pervasive worldwide and represents a potent risk factor for increased mental health burden across the lifespan. However, there is substantial individual heterogeneity in associations between adversity exposure, neurobiological changes, and mental health problems. Accounting for key features of adversity such as the developmental timing of exposure may clarify associations between adversity, neurodevelopment, and mental health. The present study leverages sparse canonical correlation analysis to characterize modes of covariation between age of adversity exposure and the integrity of white matter tracts throughout the brain in a sample of 107 adults. We find that adversity exposure during middle childhood (ages 5-6 and 8-9 in particular) is consistently linked with alterations in white matter tract integrity, such that tracts supporting sensorimotor functions display higher integrity in relation to adversity exposure while tracts supporting cortico-cortical communication display lower integrity. Further, latent patterns of tract integrity linked with adversity experienced across preschool age and middle childhood (ages 4-9) were associated with trauma-related symptoms in adulthood. Our findings underscore that adversity exposure may differentially affect white matter in a function- and developmental-timing specific manner and suggest that adversity experienced between ages 4-9 may shape the development of global white matter tracts in ways that are relevant for adult mental health.

neuroscience↗