Biology subjects

Chiem, E.

Publications and source records attributed to Chiem, E..

3 recordsLinked to original sources

bioRxiv2025

Language network functional connectivity in infancy predicts developmental language trajectories

Although developmental language delays affect approximately 10% of children in the general population, the neurodevelopmental mechanisms that support normative language acquisition, and atypicalities that may predict later language delay, across the first year of life are poorly understood. Here, resting-state fMRI data from the Baby Connectome Project was used to evaluate age-related changes in language network functional connectivity and alterations associated with suboptimal language development. Additionally, a data-driven machine learning algorithm was used to partition our sample into three groups who showed Delayed, Typical, and Advanced trajectories of language development. These groups reliably differed on several assessments of language ability during infancy and toddlerhood. Using a priori brain regions involved in adult language processing, a seed-based functional connectivity analysis showed broad age-related increases in functional synchrony and specialization throughout the infant language network. Additionally, the Delayed group showed several atypical patterns of functional connectivity with language regions. Importantly, the magnitude of connectivity differences consistently predicted later language scores at two-year outcome across several different language assessments. These findings add to our understanding of normative neurodevelopmental patterns underlying language acquisition, and identify several potential biomarkers associated with language delay that could serve as future targets to inform diagnoses and clinical interventions. HighlightsO_LIThe language network undergoes significant maturational changes during infancy C_LIO_LIWith age, functionally similar nodes integrate, while dissimilar nodes segregate C_LIO_LILanguage-delayed infants show atypical connectivity in the language network C_LIO_LIThese early atypicalities predict later language development at two-year outcome C_LIO_LIWe identify several neural signatures associated with early language delay C_LI

neuroscience↗

bioRxiv2024

Scheduled feeding improves sleep in a mouse model of Huntington's disease.

Sleep disturbances are common features of neurodegenerative disorders including Huntingtons disease (HD). The sleep and circadian disruptions are recapitulated in animal models, and these models provide the opportunity to evaluate whether circadian interventions can be effective countermeasures for neurodegenerative disease. Time restricted feeding (TRF) interventions successfully improve activity rhythms, sleep behavior and motor performance in mouse models of HD. Seeking to determine if these benefits of scheduled feeding extend to physiological measures of sleep, electroencephalography (EEG) was used to measure sleep/wake states and polysomnographic patterns in adult mice (six mo-old) under TRF and ad lib feeding (ALF). With each diet, both male and female wild-type (WT) and bacterial artificial chromosome transgenic (BACHD) mice were evaluated. Our findings show that male, but not female, BACHD mice exhibited significant changes in the temporal patterning of wake and non-rapid eye movement (NREM) sleep. The TRF intervention reduced the inappropriate early morning activity by increasing NREM sleep in the male BACHD mice. In addition, the scheduled feeding reduced sleep fragmentation (# bouts) in the male BACHD mice. The phase of the rhythm in rapid-eye movement (REM) sleep was significantly altered by the scheduled feeding. The treatment did impact the power spectral curves during the day in male but not female mice. Sleep homeostasis, as measured by the response to six hours of gentle handling, was not altered by the diet. Thus, TRF improves the temporal patterning and fragmentation of NREM sleep without impacting sleep homeostasis. This work adds critical support to the view that sleep is a modifiable risk factor in neurodegenerative diseases.

neuroscience↗

bioRxiv2023

Sex Differences in Sleep Phenotypes in the BACHD Mouse Model of Huntington's Disease

Sleep and circadian rhythm disturbances are common features of Huntingtons disease (HD). HD is an autosomal dominant neurodegenerative disorder that affects men and women in equal numbers, but some epidemiological studies as well as preclinical work indicate there may be sex differences in disease progression. Since sex differences in HD could provide important insights to understand cellular and molecular mechanism(s), we used the bacterial artificial chromosome transgenic mouse model of HD (BACHD) to examine whether sex differences in sleep/wake cycles are detectable in an animal model of the disease. Electroencephalography/electromyography (EEG/EMG) was used to measure sleep/wake states and polysomnographic patterns in young adult (12 week-old) male and female wild-type and BACHD mice. Our findings show that male, but not female, BACHD mice exhibited increased variation in phases of the rhythms as compared to age and sex matched wild-types. For both Rapid-eye movement (REM) and Non-rapid eye movement (NREM) sleep, genotypic and sex differences were detected. In particular, the BACHD males spent less time in NREM and exhibited a more fragmented sleep than the other groups. Both male and female BACHD mice exhibited significant changes in delta but not in gamma power compared to wild-type mice. Finally, in response to a 6-hrs sleep deprivation, both genotypes and sexes displayed predicted homeostatic responses to sleep loss. These findings suggest that females are relatively protected early in disease progression in this HD model. Significance StatementSleep and circadian rhythm disturbances are common features of Huntingtons disease (HD). Using an animal model of HD and EEG measures of sleep, we found that the males were more vulnerable to sleep/wake architecture alterations and sleep fragmentation. Homeostatic recovery from sleep loss did not appear to be altered at this stage of the disease. These findings raise the possibility that sex-specific factors play a role in the HD symptom progression and that hormone-based treatments may have therapeutic utility.

neuroscience↗