A meta-analysis of fMRI studies of language comprehension in children

The neural representation of language comprehension has been examined in several meta-analyses of fMRI studies with human adults. To complement this work from a developmental perspective, we conducted a meta-analysis of fMRI studies of auditory language comprehension in human children. Our analysis included 27 independent experiments involving n = 625 children (49% girls) with a mean age of 8.9 years. Activation likelihood estimation and seed-based effect size mapping revealed activation peaks in the pars triangularis of the left inferior frontal gyrus and bilateral superior and middle temporal gyri. In contrast to this distribution of activation in children, previous work in adults found activation peaks in the pars opercularis of the left inferior frontal gyrus and more left-lateralized temporal activation peaks. Accordingly, brain responses during language comprehension may shift from bilateral temporal and left pars triangularis peaks in childhood to left temporal and pars opercularis peaks in adulthood. This shift could be related to the gradually increasing sensitivity of the developing brain to syntactic information

Cherenkov-dE/dx-range measurements on cosmic ray iron group nuclei

A balloon experiment which combined a large area plastic detector unit with electronic dE/dx-C data is presented. The correlation of the electronic data with the range data of the plastic detector stack was achieved by rotating plastic detector disks which provided in this way the passive plastic detector with an incorporated time determination. The constant flux of cosmic ray particles with charge Z greater than two was used to gauge the time resolving system. Stopping cosmic ray iron group nuclei in the energy range 400 to 700 MeV/nuc are identified using their electronic scintillator and Cherenkov signals and their etch conelengths and range data. The precise knowledge of the particle's trajectory proposes refined pathlength corrections to the electronic data

A meta-analysis of fMRI studies of semantic cognition in children

Our capacity to derive meaning from things that we see and words that we hear is unparalleled in other animal species and current AI systems. Despite a wealth of functional magnetic resonance imaging (fMRI) studies on where different semantic features are processed in the adult brain, the development of these systems in children is poorly understood. Here we conducted an extensive database search and identified 50 fMRI experiments investigating semantic world knowledge, semantic relatedness judgments, and the differentiation of visual semantic object categories in children (total N = 1,018, mean age = 10.1 years, range 4–15 years). Synthesizing the results of these experiments, we found consistent activation in the bilateral inferior frontal gyri (IFG), fusiform gyri (FG), and supplementary motor areas (SMA), as well as in the left middle and superior temporal gyri (MTG/STG). Within this system, we found little evidence for age-related changes across childhood and high overlap with the adult semantic system. In sum, the identification of these cortical areas provides the starting point for further research on the mechanisms by which the developing brain learns to make sense of its environment

Distrust before first sight: Knowledge- and appearance-based effects of trustworthiness on the visual consciousness of faces

Not all visual stimuli processed by the brain reach the level of conscious perception. Previous research has shown that the emotional value of a stimulus is one of the factors that can affect whether it is consciously perceived. Here, we investigated whether social-affective knowledge influences a face’s chance to reach visual consciousness. Furthermore, we took into account the impact of facial appearance. Faces differing in facial trustworthiness (i.e., being perceived as more or less trustworthy based on appearance) were associated with neutral or negative socially relevant information. Subsequently, an attentional blink task was administered to examine whether the manipulated factors affect the faces’ chance to reach visual consciousness under conditions of reduced attentional resources. Participants showed enhanced detection of faces associated with negative as compared to neutral social information. In event-related potentials (ERPs), this was accompanied by effects in the time range of the early posterior negativity (EPN) component. These findings indicate that social-affective person knowledge is processed already before or during attentional selection and can affect which faces are prioritized for access to visual consciousness. In contrast, no clear evidence for an impact of facial trustworthiness during the attentional blink was found

Magnetoelectric Coupling and Electric Control of Magnetization in Ferromagnet-Ferroelectric-Metal Superlattices

Ferromagnet-ferroelectric-metal superlattices are proposed to realize the large room-temperature magnetoelectric effect. Spin dependent electron screening is the fundamental mechanism at the microscopic level. We also predict an electric control of magnetization in this structure. The naturally broken inversion symmetry in our tri-component structure introduces a magnetoelectric coupling energy of $P M^2$. Such a magnetoelectric coupling effect is general in ferromagnet-ferroelectric heterostructures, independent of particular chemical or physical bonding, and will play an important role in the field of multiferroics.Comment: 5 pages including 3 figures and 1 tabl

A meta‐analysis of mental rotation in the first years of life

Mental rotation, the cognitive process of moving an object in mind to predict how it looks in a new orientation, is coupled to intelligence, learning, and educational achievement. On average, adolescent and adult males solve mental rotation tasks slightly better (i.e., faster and/or more accurate) than females. When such behavioral differences emerge during development, however, remains poorly understood. Here we analyzed effect sizes derived from 62 experiments conducted in 1705 infants aged 3–16 months. We found that male infants recognized rotated objects slightly more reliably than female infants. This difference survives correction for small degrees of publication bias. These findings indicate that gender differences in mental rotation are small and not robustly detectable in the first months of postnatal life.German Research Foundation http://dx.doi.org/10.13039/501100001659European Research Council http://dx.doi.org/10.13039/100010663Jacobs Foundation Research ScholarshipStudienstiftung des deutschen VolkesPeer Reviewe

Singular values of some modular functions

We study the properties of special values of the modular functions obtained from Weierstrass P-function at imaginary quadratic points.Comment: 19 pages,corrected typo

Generation of Relativistic Electron Bunches with Arbitrary Current Distribution via Transverse-to-Longitudinal Phase Space Exchange

We propose a general method for tailoring the current distribution of relativistic electron bunches. The technique relies on a recently proposed method to exchange the longitudinal phase space emittance with one of the transverse emittances. The method consists of transversely shaping the bunch and then converting its transverse profile into a current profile via a transverse-to-longitudinal phase-space-exchange beamline. We show that it is possible to tailor the current profile to follow, in principle, any desired distributions. We demonstrate, via computer simulations, the application of the method to generate trains of microbunches with tunable spacing and linearly-ramped current profiles. We also briefly explore potential applications of the technique.Comment: 13 pages, 17 figure

Computing Hilbert Class Polynomials

We present and analyze two algorithms for computing the Hilbert class polynomial $H_D$ . The first is a p-adic lifting algorithm for inert primes p in the order of discriminant D < 0. The second is an improved Chinese remainder algorithm which uses the class group action on CM-curves over finite fields. Our run time analysis gives tighter bounds for the complexity of all known algorithms for computing $H_D$, and we show that all methods have comparable run times