Biology subjects

Alemu, K.

Publications and source records attributed to Alemu, K..

3 recordsLinked to original sources

bioRxiv2024

Decreased BOLD signal variability in middle-aged and older adults on the Autism Spectrum

PurposeAutism spectrum disorder (ASD) is a lifelong neurodevelopmental disorder. Preliminary evidence suggests an increased risk for accelerated or early-onset cognitive and neurological decline in ASD. While it is well established that brain development in children, adolescents and young adults with ASD diverges from neurotypical (NT) peers, it is unknown how brain function is impacted in older adults with ASD. Understanding age-related changes of brain function in ASD is crucial to establish best practices for cognitive and health screenings in adults with ASD and develop interventions that might reduce the risk of accelerated decline. Decreases in blood-oxygenation-level-dependent (BOLD) signal variability (BSV) in typical aging have been shown across multiple studies, likely reflecting declining Gamma-Aminobutyric Acid (GABA) activity, and is associated with poorer cognitive performance. We hypothesized that adults with ASD would show reduced BSV compared to the NT group, with steeper negative age associations in the ASD than NT group. MethodsThe study assessed BSV in a cohort of adults (40-70 years), 28 with ASD and 39 age-matched NT. General linear models tested for main effects of diagnostic group (ASD, NT), age and group-by-age interactions (controlling for RMSD). LimitationsOur cross-sectional data and small sample size highlight the need for longitudinal analyses in larger cohorts, alongside exploring links to cognitive function. Additionally, psychotropic medications used by our cohort of adults on the autism spectrum may have affected BSV. ResultsSignificant group-by-age interactions were observed for the right insular, left temporal occipital fusiform, right frontal orbital and right inferior lateral occipital cortex, with BSV showing strong negative associations with age in the ASD but not NT group. ConclusionThese findings suggest that BSV decreases may occur earlier in adults on the autism spectrum compared to their neurotypical peers, possibly indicating accelerated aging. However, given limited prior research, additional longitudinal analyses will be necessary to determine if the results presented truly reflect accelerated aging or arise from lifelong persistent differences in brain function.

neuroscience↗

bioRxiv2021

Increased heterogeneity and task-related reconfiguration of functional connectivity within a lexicosemantic network in autism

Autism spectrum disorder (ASD) is highly heterogeneous in etiology and clinical presentation. Findings on intrinsic functional connectivity (FC) or task-induced FC in ASD have been inconsistent including both over- and underconnectivity and diverse regional patterns. As FC patterns change across different cognitive demands, a novel and more comprehensive approach to network architecture in ASD is to examine the change in FC patterns between rest and task states, referred to as reconfiguration. This approach is suitable for investigating inefficient network connectivity that may underlie impaired behavioral functioning in clinical disorders. We used functional magnetic resonance imaging (fMRI) to examine FC reconfiguration during lexical processing, which is often affected in ASD, with additional focus on interindividual variability. Thirty adolescents with ASD and a matched group of 23 typically developing (TD) participants completed a lexicosemantic decision task during fMRI, using multiecho-multiband pulse sequences with advanced BOLD signal sensitivity and artifact removal. Regions of interest (ROIs) were selected based on task-related activation across both groups, and FC and reconfiguration were compared between groups. The ASD group showed increased interindividual variability and overall greater reconfiguration than the TD group. An ASD subgroup with typical performance accuracy (at the level of TD participants) showed reduced similarity and typicality of FC during the task. In this ASD subgroup, greater FC reconfiguration was associated with increased language skills. Findings suggest that intrinsic functional networks in ASD may be inefficiently organized for lexicosemantic decisions and may require greater reconfiguration during task processing, with high performance levels in some individuals being achieved through idiosyncratic mechanisms. HighlightsFC reconfiguration is a comprehensive approach to examining network architecture Functional networks are inefficiently organized for lexicosemantic decisions in ASD ASD may require greater reconfiguration during task processing Some ASD individuals achieve high performance through idiosyncratic mechanisms

neuroscience↗

bioRxiv2019

Diversified Diet Feeding Practice is Low Compared to the WHO Recommendation in the Dabat Demographic and Health Surveillance System Site: Finding from the Baseline Survey of Nutrition Project, 2016

IntroductionImproving infant and young child feeding practices is critical to improved nutrition, health, and development of children. The country of Ethiopia has also adopted the WHO recommendations of child feeding practices and developed the national guideline of infant and young child feeding to improve childs nutrition and health status. However, a few children start and received appropriate complementary feeding based on the recommendation. Therefore, the study aimed to determine dietary diversity score and its associated factors among under five children at Dabat Demography Surveillance System site (HDSS), northwest Ethiopia. MethodsA cross-sectional community based study was from February to June 2016. All children aged 6-59 months old who lived in HDSS site were included in the survey. The collected data were checked and entered into Epi info version 7 and exported to STATA version 14 statistical software for analysis. Both crude odds ratio (COR) and adjusted odds ratio (AOR) with the corresponding 95% confidence interval (CI) was calculated to show the strength of association. Finally, a p-value of 0.05 was used to determine if the association was statistically significant. ResultsIn this study, about 34.87% (95%CI: 33.27, 36.49%) of the children received adequately diversified diet. The odds of receiving adequately diversified diet was higher among children whose mother had secondary and above education (AOR= 6.51; 95%CI: 4.95, 8.56), mother who had ANC (AOR = 1.90; 95%CI: 1.60, 2.26) and PNC visit (AOR= 1.31; 95%CI: 1.00, 1, 72). However, a lower dietary diversity score is observed among young children (AOR=0.59; 95%CI: 0.41, 0.85), and children from food inscured household (AOR=0.76; 95%CI: 0.63, 0.92). ConclusionsDiversified diet feeding practice is low compared to the WHO recommendation in the surveillance site. Age of the child, maternal education, ANC and PNC visit, and household food insecurity were significantly associated with Dietary diversity score of children. Hence, various actions need to scale up the current practices of child feeding by improving HHFSS, strengthening ANC and PNC counselling about child feeding options, and feeding of young infants.

epidemiology↗