publications
publications by categories in reversed chronological order. generated by jekyll-scholar.
2026
- Neonatal Brain-Age Models in Full- and Preterm InfantsHoward Chiu, Adam Richie-Halford, Molly F Lazarus, and 7 more authorsbioRxiv, Jan 2026
Prematurity affects brain development and increases risk for neurodevelopmental impairments. Yet reliable biomarkers for at-risk infants remain limited. The goals of this study are (1a) to construct a white matter neonatal brain-age model including full-term and preterm neonates from a large publicly-available data set, (1b) to evaluate the accuracy of this model for characterizing the preterm brain from the same data set; (2) to determine if a similar model can predict brain-age based on clinical MRI scans from high-risk neonates born preterm; and (3) to evaluate whether this predictive model provides information about the infant’s health beyond conventional clinical and demographic measures. We developed brain-age prediction models using diffusion magnetic resonance imaging-derived white matter features from two datasets: (1) the developing Human Connectome Project (dHCP; 368 healthy infants) and (2) a clinical sample collected at the Lucile Packard Children’s Hospital (LPCH; 162 high-risk preterm infants). White matter features demonstrated strong predictive performance in the dHCP dataset (within 3.9 days) and the LPCH clinical dataset (within 6.6 days). However, brain-age metrics (i.e., brain-age gap) showed no significant associations with health complications measured by a composite score of common prematurity complications. While tractometry-derived brain-age models accurately characterize brain maturation in the neonatal brain, their sensitivity to clinical complications in preterm infants appears limited. Global white matter maturation measures derived from clinical grade data may be insufficiently sensitive to capture the cumulative burden of prematurity-related morbidities, suggesting need for multimodal or longitudinal biomarkers.
2024
- Estimating the Replicability of Psychology Experiments After an Initial Failure to ReplicateVeronica Boyce, Ben Prystawski, Adani B. Abutto, and 17 more authorsCollabra: Psychology, Nov 2024
When a replication fails, scientists have to decide whether to make a second attempt or move on. Psychology researchers who attempt to replicate studies often face this decision, given the empirical rate of replication success in psychology, which is lower than desired. Here, we report 17 re-replications of experiments for which an original replication had failed. In 5/17 of these “rescue” projects (29%), the “rescue” study mostly or fully replicated the original results, albeit with a smaller effect size; in the other 12, the second replication was also judged to have failed. We speculate that successful rescue projects were due to larger sample sizes or methodological changes such as attention checks. In the absence of obvious weaknesses in a failed replication study’s sample or procedure, however, it may be most efficient to stop pursuing an effect after a single failed replication.
2021
- Prefrontal and frontostriatal structures mediate academic outcomes associated with ADHD symptomsHoward Chiu, Sila Genc, Charles B. Malpas, and 4 more authorsBrain Disorders, Dec 2021
Children with attention-deficit/hyperactivity disorder (ADHD) have poor academic functioning compared to typically developing children, with executive dysfunction mediating the relationship between ADHD symptoms and academic outcomes. This study investigated whether differences in prefrontal and frontostriatal structures explain this mediating relationship. 132 children aged 9–11 years (mean 10.4 years) completed a MRI including structural and diffusion acquisitions. Cortical regions were parcellated using Freesurfer. Frontostriatal tracts were generated using constrained spherical deconvolution (CSD) tractography. Executive functioning was assessed using working memory, sustained attention and response inhibition tasks. Academic achievement was measured by direct assessment of reading and mathematics, teacher report of academic competence, and national standardized academic testing. Serial mediation analysis tested whether executive function and frontostriatal structures mediate the poorer academic functioning seen in ADHD. Symptom severity (predominantly inattention) was associated with poorer academic outcomes. Working memory partially mediated the relationship between symptoms and academic outcomes. In a serial mediation model, left DLPFC volume, right orbitofrontal volume, and left striatal structures to DLPFC tract volumes partially mediated academic outcome. This study suggests that variability in frontostriatal structures explain the mediating effect of cognitive performance on the relationship between ADHD symptomatology and academic outcomes.