bioRxiv Science⌕ Search

Biology subjects

Wild, C.

Publications and source records attributed to Wild, C..

At least 19 recordsLinked to original sources

Microclimatic heterogeneity is associated with forest structural complexity and biodiversity

Forest microclimates, their dependence on forest structure, and their impact on biodiversity are crucial for future forest management under climate change. However, standard approaches for measuring forest microclimates do not capture within-plot heterogeneity, which, according to the habitat heterogeneity hypothesis, is a key driver of local biodiversity. We quantified horizontal and vertical microclimatic heterogeneity within 30 broad-leaved forest plots in Central Europe using a three-dimensional design with high spatial resolution. Moreover, we examined whether microclimatic heterogeneity differs among silvicultural treatments and whether it can be predicted using forest structure indices derived from laser scanning. Additionally, we explored the relationship between microclimatic heterogeneity and biodiversity. In the understory of canopy gaps, warm and cold habitats co-existed in close proximity, leading to a high horizontal microclimatic heterogeneity. In closed stands with high structural complexity, we found steep gradients of increasing temperature and vapor pressure deficit from the ground to the canopy during mid-day. Canopy cover and forest structural complexity were strong indicators of microclimatic heterogeneity. We found positive relationships between herb layer temperature heterogeneity and the diversity of plants, Hymenoptera, and Diptera. Our results demonstrate that single-point measurements fail to capture the substantial microclimatic heterogeneity within plots, potentially misrepresenting the conditions experienced by forest species. However, laser scanning provides reliable indicators for within- plot microclimatic heterogeneity. With canopy gaps featuring high horizontal microclimatic heterogeneity and promoting the biodiversity of several taxonomic groups, we argue that managing forests for maximized temperature buffering should not be the only strategy to conserve forest biodiversity. HighlightsO_LIHigh small-scale horizontal microclimatic heterogeneity in canopy gaps C_LIO_LISteep vertical microclimatic gradients in closed-canopy forests C_LIO_LICanopy cover and structural complexity: indicators for microclimatic heterogeneity C_LIO_LIPositive relationship between herb layer temperature heterogeneity and biodiversity C_LI

ecology↗

The Invisible Heterogeneity of a Forest -- Beta Diversity of Volatiles

Forest structural heterogeneity affects biodiversity, yet how changes in forest structure influence the spatial patterns of forest chemical heterogeneity remains poorly understood. Volatile organic compounds (VOCs) create invisible chemical landscapes that influence forest ecosystem processes, but whether VOC {beta}-diversity patterns respond to silviculture or disturbance caused heterogeneity remains unknown. We quantified how enhanced structural beta complexity (ESBC) treatments affect VOC {beta}-diversity patterns and investigated potential drivers and ecological effects in temperate production forests. Using the experimental BETA-FOR framework, we sampled ambient forest air at the forest floor and 1 m heights across 234 forest patches in six German regions using Tenax/Carboxen adsorbent traps analyzed via TD-GCMS. Results from generalized linear beta regression models showed that {beta}-diversity of VOCs increased significantly at 1 m height in ESBC forests compared to control forests, but this increase was not significant at the forest floor. In contrast to studies on plants, fungi and animals, the main driver for increasing beta-diversity in VOCs was not the heterogeneity of canopy openness, but the amount of deadwood. Using saproxylic beetles as a test group, we found that saproxylic beetle community dissimilarity increased with VOC dissimilarity, but only for forest floor VOCs. Our finding adds a new component to the framework of habitat heterogeneity, the invisible gradient of volatile diversity utilized by many forest organisms. Furthermore, we provide the first evidence that enhancing the heterogeneity of forests, and particularly of the dead wood, increase not only the structural heterogeneity but also the volatile {beta}-diversity.

ecology↗

Temperate forest heterogeneity decreases local and landscape-scale spider diversity through habitat filtering despite species turnover

O_LISpiders are key components of forest food webs, making use of the three-dimensional forest structure. Yet modern silviculture has homogenized temperate forest structure at local and landscape scales. The consequences of this homogenization for landscape-level spider diversity, however, remain largely unknown. C_LIO_LITherefore, we sampled spiders using pitfall traps across 234 patches in a large-scale, replicated field experiment at 11 paired European beech (Fagus sylvatica) forest sites in Germany. In one district per site, we experimentally diversified between-forest-patch complexity (ESBC) through canopy gap creation and deadwood enrichment and kept a second district untreated as a structurally homogeneous control. C_LIO_LIWe applied a novel meta-analytic framework to compare -, {beta}-, and {gamma}-diversity of spiders between treatment and control districts, standardized for sample coverage, along Hill numbers giving increasing weight to abundance and for taxonomic, functional, and phylogenetic diversity. To gain a deeper insight into the effects of our intervention on the processes affecting the assembly of spider communities, we investigated the response of functional-phylogenetic diversity quantified by standardized effect sizes of mean pairwise distances (SES MFPD) to our treatments. C_LIO_LIBased on 18,540 spider individuals from 206 species, treatment districts exhibited significantly lower {gamma}- and -diversity across all diversity facets and Hill numbers, particularly when focusing on rare species (q = 0). In contrast, {beta}-diversity increased in treatment districts for phylogenetic and functional diversity across all Hill numbers (q = 0, 1, 2). Although spider abundances were higher in treatment patches, functional-phylogenetic diversity decreased in gaps and ESBC districts in general, indicating a shift from limiting similarity towards habitat filtering. C_LIO_LIOur findings corroborate earlier results of high abundances but lower taxonomic and functional diversity in canopy gaps due to strong habitat filtering effects, resulting in overall lower -diversity, which cannot be compensated by increasing {beta}-diversity. Hence, the greater three-dimensional complexity of homogeneous forests supports more diverse spider metacommunities at the {gamma}-scale, particularly when controlling for sample coverage, suggesting that canopy spider diversity in temperate forests may be underestimated. Nonetheless, higher abundances in treatment districts point to increased predator pressure and greater prey availability in structurally diversified forests. C_LI

ecology↗

Higher bat and bird γ-diversity in structurally complex forests is driven by distinct α- and β-diversity responses

Effective conservation management and habitat restoration rely on understanding how biodiversity responds to environmental change. Centuries of silviculture have homogenized forests and their species communities globally, reducing biodiversity. To test whether restoring forest structural complexity can promote biodiversity, we conducted a large-scale, spatially explicit landscape experiment. At 11 sites across Germany, we compared bat and bird diversity in forests with experimentally enhanced heterogeneity by increasing deadwood and canopy complexity to homogeneous production forests. Both taxa were investigated by autonomous acoustic recorders and automatic species identification. We quantified within-patch (-), between-patch ({beta}-), and landscape-level ({gamma}-) diversity, emphasizing infrequent to highly frequent species for taxonomic, functional, and phylogenetic diversity. The pairwise comparisons of the sites were synthesized using a newly developed meta-analysis of rarefaction-extrapolation curves. {gamma}-diversity increased significantly in structurally heterogeneous forests for both taxa, albeit through distinct taxon-specific mechanisms. Bat {gamma}-diversity gains were primarily driven by higher {beta}-diversity, indicating greater dissimilarity in species assemblages among patches, while bird {gamma}-diversity increased via higher -diversity within patches. Bat diversity increases were mainly taxonomic, suggesting functional similarity in the communities, whereas birds showed the highest gains in functional diversity, indicating that experimental treatments resulted in greater trait dissimilarity. Our results provide experimental evidence under real-world conditions that {gamma}-diversity can be shaped by different diversity mechanisms. These patterns likely originate from differences in activity ranges, such as the large-scale movements of foraging bats in contrast to the more spatially restricted, territorial behavior of birds. This highlights the need for taxon-specific restoration strategies in homogenized landscapes.

ecology↗

Dung beetles do not profit from enhanced spatial heterogeneity in production forests: a large-scale forest manipulation experiment

O_LICentral European forest management strategies promoting structurally homogeneous closed-canopy forests have led to landscape-level declines in biodiversity and ecosystem multifunctionality. Conservation-targeted management programs aim at reintroducing structural heterogeneity into production forests, however, it is not well understood if species diversity and ecosystem functions generally profit from management promoting heterogeneity in forest structure. By removing and processing mammalian dung remains, dung beetles play an integral role in ecosystem functions in forests. C_LIO_LIIn one of the largest manipulative forest experiments in Central Europe to date, we analysed the effects of enhanced structural heterogeneity in production forests, climate, and mammalian defecation on dung beetle diversity and dung removal rates at the local and landscape level. We assessed communities of dung beetles and dung removal rates on 234 study patches (50 x 50 m) in eleven paired forest landscapes across a climatic gradient in Germany. Forest landscapes were either managed to conserve a homogeneous closed canopy or to create a heterogeneous forest structure with forest patches varying in canopy coverage and dead wood availability. C_LIO_LIWe did not find that more heterogeneously managed forests had higher dung beetle species diversity and dung removal rates. Canopy openings did not increase species turnover but decreased species diversity. C_LIO_LIAlong the climate gradient, dung beetle average biomass and dung removal decreased with increasing temperature. Canopy openings in combination with higher temperatures negatively impacted all abundant dung beetle species, but especially the large species Anoplotrupes stercorosus, comprising > 90% of the total dung beetle biomass. C_LIO_LISynthesis and application: Our results suggest that dung beetles do not profit from management increasing the structural heterogeneity of forests. Due to a restricted climate and habitat niche of the current Central European dung beetle fauna, future warming and openings in forest structure might have negative effects on dung beetles and consequently on the ecosystem services they provide in Central European production forests. C_LI

ecology↗

Selective breeding enhances coral heat tolerance even over small spatial scales

Coral reefs globally are experiencing escalating mass bleaching and mortality. Reefs along the western Indian Ocean have been relatively unimpacted. We assessed heat tolerance baselines in two widespread reef-building Acropora species and used selective breeding from two thermally distinct (present day and stress histories) northern (Mean Monthly Maximum 27.9 {degrees}C) and southern (26.6 {degrees}C) reefs along the Ningaloo World Heritage Reef. Fitness responses were measured in control and heat stress temperatures (adults = 31.0 {degrees}C, larvae = 35.5 {degrees}C), including survival, tissue necrosis, bleaching, and photosynthesis. Larvae with one parent from the warmer population exhibited >2.2-fold higher survival under heat stress, while those with both parents from the warmer population survived 1.6-fold better (compared to control larvae with two parents from the cooler population). Photosynthesis was maintained in both species and both populations, suggesting heat responses were host driven. Adults from both populations from one species (A. tenuis) exhibited similar responses to heat, while the other (A. millepora) was more variable. These findings are the first to demonstrate that selective breeding can provide heat tolerance enhancement for corals in the Indian Ocean and will be critical to preparing for future marine heatwaves.

ecology↗

Nitrification in a seagrass-sponge association

AO_SCPLOWBSTRACTC_SCPLOWIn the Mediterranean Sea, the demosponge Chondrilla nucula can occur in close association with the native seagrass Posidonia oceanica. C. nucula harbors a diverse and abundant microbial community, including potential nitrifiers. Thus, the sponge may contribute to the nitrogen (N) demand of the seagrass holobiont. In this study, we investigated potential nitrification rates (PNR) and inorganic N fluxes within this association at a site where C. nucula covered 18 {+/-} 3 % of the seagrass meadow area, during plant growth (spring) and senescence (autumn). Using incubation experiments with 15N-labeled ammonium, we measured PNR and inorganic N of the seagrass-sponge association, and of sponge and seagrass independently, under light and dark conditions. We supplemented these experiments with 16s rRNA gene amplicon sequencing to characterize the microbial community of the sponge. PNR was exclusively measured when the sponge was present (alone or in association with the seagrass). PNR was highest in the dark and when C. nucula was associated with the seagrass, ranging from 21 {+/-} 7 to 267 {+/-} 33 nmol N g DW-1 h-1 in spring and autumn, respectively. Sponge-mediated PNR can support 8% of the N demand of the P. oceanica holobiont during growth and 47 % during senescence. We identified key nitrifying bacterial and archaeal groups as members of the sponges microbial community. While C. nucula released inorganic N, potentially sustaining the seagrass, it benefitted from dissolved organic carbon released by P. oceanica. These results suggest that the interaction between C. nucula and P. oceanica is mutually beneficial, ultimately supporting and stabilizing the seagrass ecosystem.

ecology↗

Reciprocal nutritional benefits in a sponge-seagrass association

Sponges commonly form associations within seagrass meadows, but their potential impact on seagrass productivity and nutrient cycles remains poorly understood. This study investigates the association between the demosponge Chondrilla nucula and the Mediterranean seagrass Posidonia oceanica in two sampling occasions during the plant growth (spring) and senescence (autumn) seasons at a small inlet near Naples, Italy, where the sponge grows conspicuously within the seagrass bed. We found a non-linear relationship between the benthic cover of the sponge and the seagrass, with higher C. nucula cover linked to intermediate P. oceanica cover, suggesting spatial dependence. P. oceanica showed higher net primary production (NPP) in spring, while C. nucula was net heterotrophic in spring but exhibited slightly positive NPP in autumn. NPP remained stable when the two organisms were associated, regardless of the season. C. nucula consistently contributed inorganic nutrients to the association in the form of phosphate, ammonium, and substantial nitrate, recycling nutrients that potentially benefited P. oceanica in its growth season. In return, the seagrass consistently provided dissolved organic carbon, which aided sponge nutrition in spring. These findings suggest reciprocal benefits in the interaction between C. nucula and P. oceanica, with nutrient exchange facilitating a facultative mutualism that potentially supports and stabilizes the productivity of the seagrass ecosystem. SIGNIFICANCE STATEMENTThis study provides a novel exploration of the reciprocal interactions between the demosponge Chondrilla nucula and the Mediterranean seagrass Posidonia oceanica, revealing a facultative mutualism mediated by nutrient exchange. Our findings show a non-linear spatial dependence between sponge and seagrass cover and demonstrate the sponges substantial contributions of inorganic nutrients (phosphate, ammonium and conspicuous nitrate) to the seagrass, particularly during its productive spring season. In return, P. oceanica supplies dissolved organic matter, aiding sponge nutrition. This study uniquely quantifies these reciprocal nutrient exchanges across the plant growth and senescence seasons, demonstrating how such interactions stabilize net primary production and support ecosystem functioning. These insights address a critical gap in understanding the role of sponge-seagrass associations in nutrient cycling, highlighting their significance for the resilience, productivity, and metabolic balance of coastal ecosystems under changing environmental conditions.

ecology↗

Identifying novel chemical matter against the Chikungunya virus nsP3 macrodomain through crystallographic fragment screening

Chikungunya virus (CHIKV) causes severe fever, rash and debilitating joint pain that can last for months 1,2or even years. Millions of people have been infected with CHIKV, mostly in low and middle-income countries, and the virus continues to spread into new areas due to the geographical expansion of its mosquito hosts. Its genome encodes a macrodomain, which functions as an ADP-ribosyl hydrolase, removing ADPr from viral and host-cell proteins interfering with the innate immune response. Mutational studies have shown that the CHIKV nsP3 macrodomain is necessary for viral replication, making it a potential target for the development of antiviral therapeutics. We, therefore, performed a high-throughput crystallographic fragment screen against the CHIKV nsP3 macrodomain, yielding 109 fragment hits covering the ADPr-binding site and two adjacent subsites that are absent in the homologous macrodomain of SARS-CoV-2 but may be present in other alphaviruses, such as Venezuelan equine encephalitis virus (VEEV) and eastern equine encephalitis virus (EEEV). Finally, a subset of overlapping fragments was used to manually design three fragment merges covering the adenine and oxyanion subsites. The rich dataset of chemical matter and structural information discovered from this fragment screen is publicly available and can be used as a starting point for developing a CHIKV nsP3 macrodomain inhibitor.

biochemistry↗

Molecular hydrogen can minimize negative effects of heat stress on the hard coral genus Acropora

Coral reefs are increasingly threatened by mass bleaching events due to global ocean warming. Novel management strategies are urgently needed to support coral survival until global efforts can mitigate ocean warming. Given the strong antioxidant, anti-inflammatory and anti-apoptotic properties of molecular hydrogen, our study explores its potential to alleviate the negative effects of heat stress on corals. We investigated the ecophysiological responses of two common hard corals (Acropora spp. and Pocillopora verrucosa) from the Central Red Sea under ambient (26 {degrees}C) and elevated seawater temperatures (32 {degrees}C), with and without hydrogen addition ([~] 150 {micro}M H2) over 48 h. Our results showed that at 32 {degrees}C without hydrogen addition, P. verrucosa exhibited high temperature tolerance, whereas Acropora spp. showed significant reductions in photosynthetic efficiency and maximum electron transport rate compared to the ambient condition (26 {degrees}C). The addition of hydrogen at 32 {degrees}C increased the maximum electron transport rate of Acropora spp. by 28 %, maintaining it at levels compared to those at 26 {degrees} C. This suggests that molecular hydrogen benefits specific coral species under heat stress in the short-term. This study provides the foundation for future long-term and in-situ studies, potentially guiding the development of new management strategies aiming at enhancing coral resilience to ocean warming.

ecology↗

Crystallographic fragment screen of Enterovirus D68 3C protease and iterative design of lead-like compounds using structure-guided expansions

The development of effective broad-spectrum antivirals forms an important part of preparing for future pandemics. One cause for concern is the currently emerging pathogen Enterovirus D68 (EV-D68) which primarily spreads through respiratory routes causing mostly mild to severe respiratory illness but, in severe cases, acute flaccid myelitis. The 3C protease of EV-D68 (3Cpro) is a potential target for the development of antiviral drugs due to its essential role in the viral life cycle and high sequence conservation amongst family members. In this study, we describe the identification of fragments which bind to3Cpro using crystallographic screening and the expansion of these into more lead-like compounds. The hits revealed interesting directions for hit-to-lead progression, specifically the importance of the pocket occupied by the conserved glutamine sidechain of the substrates and the interactions formed. Additionally, two pockets could be joined by not following the backbone of the native substrates, thus circumventing the screening issues arising from the flexibility of the catalytic triad. These observations of the novel binding modes of the chemical matter found by this screen can help shape future drug design campaigns against 3C proteases.

biochemistry↗

Crystallographic Fragment Screen of Coxsackievirus A16 2A Protease identifies new opportunities for the development of broad-spectrum anti-enterovirals

Enteroviruses are the causative agents of paediatric hand-foot-and-mouth disease, and a target for pandemic preparedness due to the risk of higher order complications in a large-scale outbreak. The 2A protease of these viruses is responsible for the self-cleavage of the poly protein, allowing for correct folding and assembly of capsid proteins in the final stages of viral replication. These 2A proteases are highly conserved between Enterovirus species, such as Enterovirus A71 and Coxsackievirus A16. Inhibition of the 2A protease deranges capsid folding and assembly, preventing formation of mature virions in host cells and making the protease a valuable target for antiviral activity. Herein, we describe a crystallographic fragment screening campaign that identified 75 fragments which bind to the 2A protease including 38 unique compounds shown to bind within the active site. These fragments reveal a path for the development of non-peptidomimetic inhibitors of the 2A protease with broad-spectrum anti-enteroviral activity.

biochemistry↗

Short periods of decreased water flow may modulate long-term ocean acidification in reef-building corals

Ocean acidification (OA) poses a major threat to reef-building corals. Although water flow variability is common in coral reefs and modulates coral physiology, the interactive effects of flow and OA on corals remain poorly understood. Therefore, we performed a three-month OA experiment investigating the effect of changes in flow on coral physiology. We exposed the reef-building corals Acropora cytherea, Pocillopora verrucosa, and Porites cylindrica to control (pH 8.0) and OA (pH 7.8) conditions at moderate flow (6 cm s-1) and monitored OA effects on growth. Throughout the experiment, we intermittently exposed all corals to low flow (2 cm s-1) for 1.5 h and measured their photosynthesis:photosynthesis (P:R) ratio under low and moderate flow. On average, corals under OA calcified 18 % less and grew 23 % less in surface area than those at ambient pH. We observed species-specific interactive effects of OA and flow on coral physiology. P:R ratios decreased after 12 weeks of OA in A. cytherea (22 %) and P. cylindrica (28 %) under moderate flow, but were unaffected by OA under low flow. P:R ratios were stable in P. verrucosa. These results suggest that short periods of decreased water flow may modulate OA effects on some coral species, indicating that flow variability is a factor to consider when assessing long-term effects of climate change.

physiology↗

Accelerated Nitrogen Cycling on Seagrass Leaves in a High-CO2 World

Seagrass meadows form highly productive and diverse ecosystems in coastal areas worldwide, where they are increasingly exposed to ocean acidification (OA). Efficient nitrogen (N) cycling and uptake are essential to maintain plant productivity, but the effects of OA on N transformations in these systems are poorly understood. Here we show that complete N cycling occurs on leaves of the Mediterranean seagrass Posidonia oceanica, with OA affecting both N gain and loss while the prokaryotic community structure remains largely unaffected. Daily leaf-associated N2 fixation contributed to 35% of the plants N demand under ambient pH, whereas it contributed to 45% under OA. Nitrification potential was only detected under OA, and N-loss via N2 production increased, although the balance remained decisively in favor of enhanced N gain. Our work highlights the role of the N-cycling microbiome in seagrass adaptation to OA, with key N transformations accelerating towards increased N gain.

ecology↗

Parametric cognitive load reveals hidden costs in the neural processing of perfectly intelligible degraded speech

Speech is often degraded by environmental noise or hearing impairment. People can compensate for degradation, but this requires cognitive effort. Previous research has identified frontotemporal networks involved in effortful perception, but materials in these works were also less intelligible, and so it is not clear whether activity reflected effort or intelligibility differences. We used functional magnetic resonance imaging to assess the degree to which spoken sentences were processed under distraction, and whether this depended on speech quality even when intelligibility of degraded speech was matched to that of clear speech (i.e., 100%). On each trial, participants either attended to a sentence, or to a concurrent multiple object tracking (MOT) task that imposed parametric cognitive load. Activity in bilateral anterior insula reflected task demands: during the MOT task, activity increased as cognitive load increased, and during speech listening, activity increased as speech became more degraded. In marked contrast, activity in bilateral anterior temporal cortex was speech-selective, and gated by attention when speech was degraded. In this region, performance of the MOT task with a trivial load blocked processing of degraded speech whereas processing of clear speech was unaffected. As load increased, responses to clear speech in these areas declined, consistent with reduced capacity to process it. This result dissociates cognitive control from speech processing: substantially less cognitive control is required to process clear speech than is required to understand even very mildly degraded, 100% intelligible, speech. Perceptual and control systems clearly interact dynamically during real-world speech comprehension. Significance StatementSpeech is often perfectly intelligible even when degraded, e.g., by background sound, phone transmission, or hearing loss. How does degradation alter cognitive demands? Here, we use fMRI to demonstrate a novel and critical role for cognitive control in the processing of mildly degraded but perfectly intelligible speech. We compare speech that is matched for intelligibility but differs in putative control demands, dissociating cognitive control from speech processing. We also impose a parametric cognitive load during perception, dissociating processes that depend on tasks from those that depend on available capacity. Our findings distinguish between frontal and temporal contributions to speech perception and reveal a hidden cost to processing mildly degraded speech, underscoring the importance of cognitive control for everyday speech comprehension.

neuroscience↗

Crystallographic and electrophilic fragment screening of the SARS-CoV-2 main protease

COVID-19, caused by SARS-CoV-2, lacks effective therapeutics. Additionally, no antiviral drugs or vaccines were developed against the closely related coronavirus, SARS-CoV-1 or MERS-CoV, despite previous zoonotic outbreaks. To identify starting points for such therapeutics, we performed a large-scale screen of electrophile and non-covalent fragments through a combined mass spectrometry and X-ray approach against the SARS-CoV-2 main protease, one of two cysteine viral proteases essential for viral replication. Our crystallographic screen identified 71 hits that span the entire active site, as well as 3 hits at the dimer interface. These structures reveal routes to rapidly develop more potent inhibitors through merging of covalent and non-covalent fragment hits; one series of low-reactivity, tractable covalent fragments was progressed to discover improved binders. These combined hits offer unprecedented structural and reactivity information for on-going structure-based drug design against SARS-CoV-2 main protease.

biophysics↗

Category-Selective Visual Regions Have Distinctive Signatures of Connectivity in Early Infancy

The development of the ventral visual stream is shaped both by an innate proto-organization and by experience. The fusiform face area (FFA), for example, has stronger connectivity to early visual regions representing the fovea and lower spatial frequencies. In adults, category-selective regions in the ventral stream (e.g. the FFA) also have distinct signatures of connectivity to widely distributed brain regions, which are thought to encode rich cross-modal, motoric, and affective associations (e.g., tool regions to the motor cortex). It is unclear whether this long-range connectivity is also innate, or if it develops with experience. We used MRI diffusion-weighted imaging with tractography to characterize the connectivity of face, place, and tool category-selective regions in neonates (N=445), 1-9 month old infants (N=11), and adults (N=14). Using a set of linear-discriminant classifiers, category-selective connectivity was found to be both innate and shaped by experience. Connectivity for faces was the most developed, with no evidence of significant change in the time period studied. Place and tool networks were present at birth but also demonstrated evidence of development with experience, with tool connectivity developing over a more protracted period (9 months). Taken together, the results support an extended proto-organizon to include long-range connectivity that could provide additional constraints on experience dependent development.

neuroscience↗

Disruption to functional networks in neonates with perinatal brain injury predicts motor skills at 8 months

ObjectiveFunctional connectivity magnetic resonance imaging (fcMRI) of neonates with perinatal brain injury could improve prediction of motor impairment before symptoms manifest, and establish how early brain organization relates to subsequent development. Methods: This cohort study is the first to describe and quantitatively assess functional brain networks and their relation to later motor skills in neonates with a diverse range of perinatal brain injuries. Infants (n=65, included in final analyses: n=53) were recruited from the neonatal intensive care unit (NICU) and were stratified based on their age at birth (premature vs. term), and on whether neuropathology was diagnosed from structural MRI. Functional brain networks and a measure of disruption to functional connectivity were obtained from 14 minutes of fcMRI acquired during natural sleep at term-equivalent age.\n\nResultsDisruption to connectivity of the somatomotor and frontoparietal executive networks predicted motor impairment at 4 and 8 months. This disruption in functional connectivity was not found to be driven by differences between clinical groups, or by any of the specific measures we captured to describe the clinical course.\n\nConclusionfcMRI was predictive over and above other clinical measures available at discharge from the NICU, including structural MRI. Motor learning was affected by disruption to somatomotor networks, but also frontoparietal executive networks, which supports the functional importance of these networks in early development. Disruption to these two networks might be best addressed by distinct intervention strategies.

neuroscience↗