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

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

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

The Knight Anole (Anolis equestris) in Florida

In this paper, we discuss the likely modes of introduction of the Knight Anole (Anolis equestris) into and around Florida, provide data on its current geographic distribution, and summarize life history data in both its native and introduced Florida range. Our field data consist of collections made from 1992 through 2008 and locality data taken from the literature and systematic collections throughout the United States. Anolis equestris was first introduced in Miami-Dade County in 1952. The subsequent spread of this species in Florida has been both natural and assisted by human translocations to 10 additional counties, including Brevard, Broward, Collier, Highlands, Lee, Martin, Monroe, Palm Beach, Polk, and St. Lucie. Because this species is nonindigenous and known to consume a wide variety of items, including small vertebrates, it should be removed when encountered in the wild. A comprehensive study detailing its effects on the environment is needed

The Knight Anole (Anolis equestris) in Florida

In this paper, we discuss the likely modes of introduction of the Knight Anole (Anolis equestris) into and around Florida, provide data on its current geographic distribution, and summarize life history data in both its native and introduced Florida range. Our field data consist of collections made from 1992 through 2008 and locality data taken from the literature and systematic collections throughout the United States. Anolis equestris was first introduced in Miami-Dade County in 1952. The subsequent spread of this species in Florida has been both natural and assisted by human translocations to 10 additional counties, including Brevard, Broward, Collier, Highlands, Lee, Martin, Monroe, Palm Beach, Polk, and St. Lucie. Because this species is nonindigenous and known to consume a wide variety of items, including small vertebrates, it should be removed when encountered in the wild. A comprehensive study detailing its effects on the environment is needed