Early Autism Diagnosis based on Path Signature and Siamese Unsupervised Feature Compressor

Autism Spectrum Disorder (ASD) has been emerging as a growing public health threat. Early diagnosis of ASD is crucial for timely, effective intervention and treatment. However, conventional diagnosis methods based on communications and behavioral patterns are unreliable for children younger than 2 years of age. Given evidences of neurodevelopmental abnormalities in ASD infants, we resort to a novel deep learning-based method to extract key features from the inherently scarce, class-imbalanced, and heterogeneous structural MR images for early autism diagnosis. Specifically, we propose a Siamese verification framework to extend the scarce data, and an unsupervised compressor to alleviate data imbalance by extracting key features. We also proposed weight constraints to cope with sample heterogeneity by giving different samples different voting weights during validation, and we used Path Signature to unravel meaningful developmental features from the two-time point data longitudinally. Extensive experiments have shown that our method performed well under practical scenarios, transcending existing machine learning methods

Explaining variation in brood parasitism rates between potential host species with similar habitat requirements

Host specialization evolved in many parasite-host systems. Evolution and maintenance of host specificity may be influenced by host life-history traits, active host selection by the parasite, and host anti-parasite strategies. The relative importance of these factors is poorly understood in situations that offer parasites a choice between hosts with similar habitat requirements. The common cuckoo Cuculus canorus is a generalist parasite on the species level, but individual females prefer particular host species. In reed beds of the Yellow River Delta, China, two potential hosts with similar nest characteristics, Oriental reed warblers Acrocephalus orientalis and reed parrotbills Paradoxornis heudei, breed in sympatry. We found that warblers were parasitized at much higher rates than parrotbills. Both hosts recognized and rejected non-mimetic model eggs well, indicating that they have been involved in an arms-race with cuckoos. Cuckoo eggs closely resembled warbler eggs, and such eggs were mostly accepted by warblers but rejected by parrotbills. Only warblers recognized adult cuckoos as a specific threat. Both hosts were equally good at raising cuckoo chicks. Low nest density, partial isolation by breeding time, small scale differences in nest and nest site characteristics, and high rejection rates of natural cuckoo eggs are likely cumulatively responsible for the low current parasitism rate in parrotbills. This study emphasizes the importance of integrating the study of general host life-history characteristics and specific anti-parasitism strategies of hosts across all breeding stages to understand the evolution of host specificity.submittedVersionpublishedVersio

Path Signature Neural Network of Cortical Features for Prediction of Infant Cognitive Scores

Studies have shown that there is a tight connection between cognition skills and brain morphology during infancy. Nonetheless, it is still a great challenge to predict individual cognitive scores using their brain morphological features, considering issues like the excessive feature dimension, small sample size and missing data. Due to the limited data, a compact but expressive feature set is desirable as it can reduce the dimension and avoid the potential overfitting issue. Therefore, we pioneer the path signature method to further explore the essential hidden dynamic patterns of longitudinal cortical features. To form a hierarchical and more informative temporal representation, in this work, a novel cortical feature based path signature neural network (CF-PSNet) is proposed with stacked differentiable temporal path signature layers for prediction of individual cognitive scores. By introducing the existence embedding in path generation, we can improve the robustness against the missing data. Benefiting from the global temporal receptive field of CF-PSNet, characteristics consisted in the existing data can be fully leveraged. Further, as there is no need for the whole brain to work for a certain cognitive ability, a top K selection module is used to select the most influential brain regions, decreasing the model size and the risk of overfitting. Extensive experiments are conducted on an in-house longitudinal infant dataset within 9 time points. By comparing with several recent algorithms, we illustrate the state-of-the-art performance of our CF-PSNet (i.e., root mean square error of 0.027 with the time latency of 518 milliseconds for each sample)

A 4D infant brain volumetric atlas based on the UNC/UMN baby connectome project (BCP) cohort

Spatiotemporal (four-dimensional) infant-dedicated brain atlases are essential for neuroimaging analysis of early dynamic brain development. However, due to the substantial technical challenges in the acquisition and processing of infant brain MR images, 4D atlases densely covering the dynamic brain development during infancy are still scarce. Few existing ones generally have fuzzy tissue contrast and low spatiotemporal resolution, leading to degraded accuracy of atlas-based normalization and subsequent analyses. To address this issue, in this paper, we construct a 4D structural MRI atlas for infant brains based on the UNC/UMN Baby Connectome Project (BCP) dataset, which features a high spatial resolution, extensive age-range coverage, and densely sampled time points. Specifically, 542 longitudinal T1w and T2w scans from 240 typically developing infants up to 26-month of age were utilized for our atlas construction. To improve the co-registration accuracy of the infant brain images, which typically exhibit dynamic appearance with low tissue contrast, we employed the state-of-the-art registration method and leveraged our generated reliable brain tissue probability maps in addition to the intensity images to improve the alignment of individual images. To achieve consistent region labeling on both infant and adult brain images for facilitating region-based analysis across ages, we mapped the widely used Desikan cortical parcellation onto our atlas by following an age-decreasing mapping manner. Meanwhile, the typical subcortical structures were manually delineated to facilitate the studies related to the subcortex. Compared with the existing infant brain atlases, our 4D atlas has much higher spatiotemporal resolution and preserves more structural details, and thus can boost accuracy in neurodevelopmental analysis during infancy

Males and females of a polygamous songbird respond differently to mating opportunities

Parents are expected to make fine-tuned decisions by weighing the benefits of providing care to increase offspring survival against that of deserting to pursue future mating opportunities. A higher incentive for the rarer sex in the population indicates an impact of mating opportunities on parental care decisions. However, in a dynamic breeding system, deserting the offspring and searching for a new mate would influence mating opportunities for both sexes. Sex-specific costs and benefits are expected to influence males’ and females’ parenting strategies in different ways. Here, we investigated Chinese penduline tits, Remiz consobrinus, which exhibit flexible parental care strategies: uniparental care by the male or female, biparental care, and biparental desertion occur in the same population. We show that male penduline tits change their parental behavior over the breeding season; they desert clutches produced early in the season but care for the late season clutches. The change in male parenting behavior is consistent with the seasonal decline in mating opportunities. In contrast, parenting by females did not change over the breeding season, nor was it associated with seasonal variation in mate availability. Taken together, mating opportunities have different associations with parental behavior of male and female Chinese penduline tits. We recommend an inclusion of mating opportunities for both sexes simultaneously in order to understand one of the fundamental decisions in parental care evolution—care or desert