Biology subjects

Zuk, J.

Publications and source records attributed to Zuk, J..

5 recordsLinked to original sources

bioRxiv2021

Home literacy environment mediates the relationship between socioeconomic status and white matter structure in infants

The home literacy environment (HLE) in infancy has been associated with subsequent pre-literacy skill development and HLE at pre-school age has been shown to correlate with white matter organization in tracts that subserve prereading and reading skills. Furthermore, childhood socioeconomic status (SES) has been linked with both HLE and white matter organization. It is also important to understand whether the relationships between environmental factors such as HLE and SES and white matter organization can be detected as early as infancy, as this period is characterized by rapid brain development that may make white matter pathways particularly susceptible to these early experiences. Here, we hypothesized (1) an association between HLE and white matter organization in pre-reading and reading-related tracts in infants, and (2) that this association mediates a link between SES and white matter organization. To test these hypotheses, infants (mean age: 9.2 {+/-} 2.5 months, N = 18) underwent diffusion-weighted imaging MRI during natural sleep. Fractional anisotropy (FA) was estimated from the left superior longitudinal fasciculus (SLF) and left arcuate fasciculus using the automated fiber-tract quantification method. HLE was measured with the Reading subscale of the StimQ and SES was measured with years of maternal education. Self-reported maternal reading ability was also quantified and applied to all statistical models to control for confounding genetic effects. The Reading subscale of the StimQ positively related to FA in left SLF and mediated the association between maternal education and FA in the left SLF. Taken together, these findings underscore the importance of considering HLE from the start of life and may inform novel prevention and intervention strategies targeted at low-SES families to support developing infants during a period of heightened brain plasticity.

neuroscience↗

bioRxiv2020

Infant functional connectivity fingerprints predict long-term language and pre-literacy outcomes

Functional brain networks undergo extensive development within the first few years of life. Previous studies have linked infant functional connectivity to cognitive abilities in toddlerhood. However, little is known regarding the long-term relevance of functional connections established in infancy for the protracted development of higher-order abilities of language and literacy. Employing a five-year longitudinal imaging project starting in infancy, this study utilizes resting-state functional MRI to demonstrate prospective associations between infant functional connectivity fingerprints and subsequent language and foundational literacy skills at a mean age of 6.5. These longitudinal associations are preserved when key environmental influences are controlled for and are independent of emergent language abilities in infancy, suggesting early development of functional network characteristics in supporting the acquisition of high-order language and pre-literacy skills. Altogether, the current results highlight the importance of functional organization established in infancy as a neural scaffold underlying the learning process of complex cognitive functions.

neuroscience↗

bioRxiv2019

White matter in infancy is prospectively associated with language outcome in kindergarten

Language acquisition is of central importance to a childs development. Although the trajectory of acquisition is shaped by input and experience postnatally, the neural basis for language emerges prenatally. Thus a fundamental question remains unexamined: to what extent may the structural foundations for language established in infancy predict long-term language abilities? In this longitudinal neuroimaging investigation of children from infancy to kindergarten, we find that white matter organization in infancy is prospectively associated with subsequent language abilities, specifically between: (i) the left arcuate fasciculus in infancy and subsequent phonological awareness and vocabulary knowledge, and (ii) the left corticospinal tract in infancy and phonological awareness and phonological memory in kindergarten. Results are independent of age and home literacy environment. These findings directly link white matter organization in infancy with language abilities after school entry, and suggest that structural organization in infancy sets an important foundation for subsequent language development.

neuroscience↗

bioRxiv2019

Putative protective neural mechanisms in pre-readers with a family history of dyslexia who subsequently develop typical reading skills

Developmental dyslexia is a learning disability characterized by difficulties in word reading. While the prevalence in the general public is around 10-12%, an increased prevalence of 40-60% has been reported for children with a familial risk. Neural atypicalities in the reading network have been observed in children with (FHD+) compared to without (FHD-) a family history of dyslexia, even before reading onset. Despite the hereditary risk, about half of FHD+ children develop typical reading abilities (FHD+Typical) but the underlying neural characteristics and the developmental trajectories of these favorable reading outcomes remain unknown. Utilizing a retrospective, longitudinal approach, this is the first study to examine whether potential protective neural mechanisms are present before reading onset in FHD+Typical. Functional and structural brain characteristics were examined in 69 pre-readers who subsequently developed typical reading abilities (35 FHD+Typical/34 FHD-Typical) using MRI/fMRI. Searchlight-based multivariate pattern analyses identified distinct activation patterns during phonological processing between FHD+Typical and FHD-Typical in right inferior frontal (RIFG) and left temporo-parietal (LTPC) regions. Hypoactivation in LTPC was further demonstrated in FHD+Typical compared to FHD-Typical, suggesting that this previously reported neural characteristic of dyslexia is primarily associated with familial risk. Importantly, FHD+Typical pre-readers exhibited higher activation in RIFG than FHD-Typical, which was associated with increased interhemispheric functional and structural connectivity. These results suggest that putative protective neural mechanisms are already established in FHD+Typical pre-readers and may therefore support their successful reading development. Further studies are needed to investigate the functional significance and developmental trajectories of these neural mechanisms as well as their enabling factors, which has the potential to inform the design of early preventative/remediation strategies.

neuroscience↗

bioRxiv2019

Multifactorial pathways facilitate resilience among kindergarteners at risk for dyslexia: A longitudinal behavioral and neuroimaging study

Recent efforts have focused on screening methods to identify children at risk for dyslexia as early as preschool/kindergarten. Unfortunately, while low sensitivity leads to under-identification of at-risk children, low specificity can lead to over-identification, resulting in inaccurate allocation of limited educational resources. The present study focused on children identified as at-risk in kindergarten who do not subsequently develop dyslexia to specify factors associated with better reading outcomes among at-risk children. Early screening was conducted in kindergarten and a subset of children was tracked longitudinally until second grade. Potential protective factors were evaluated at cognitive-linguistic, environmental, and neural levels. Relative to at-risk kindergarteners who subsequently developed dyslexia, those who did not were characterized by significantly higher socioeconomic status (SES), speech production accuracy, and microstructure of the posterior right-hemispheric superior longitudinal fasciculus (SLF). A positive association between microstructure of the right SLF and subsequent decoding skills was found to be specific to at-risk children and not observed among typical controls. Among at-risk children, several kindergarten-age factors were found to significantly contribute to the prediction of subsequent decoding skills: microstructure of the posterior right SLF, age, gender, SES, and phonological awareness. These findings suggest that putative compensatory mechanisms are already present by the start of kindergarten. The right SLF, in conjunction with the cognitive-linguistic and socioeconomic factors identified, may play an important role in facilitating reading development among at-risk children. This study has important implications for approaches to early screening, and assessment strategies for at-risk children.

neuroscience↗