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Abstract

We present a reference genome assembly from an individual male Rhynchonycteris naso (Chordata; Mammalia; Chiroptera; Emballonuridae). The genome sequence is 2.46 Gb in span. The majority of the assembly is scaffolded into 22 chromosomal pseudomolecules, with the Y sex chromosome assembled.

Abstract

Purpose:
Assessing fluency in aphasia is diagnostically important for determining aphasia type and severity and therapeutically important for determining appropriate treatment targets. However, wide variability in the measures and criteria used to assess fluency, as revealed by a recent survey of clinicians (Gordon & Clough, 2022), results in poor reliability. Furthermore, poor specificity in many fluency measures makes it difficult to identify the underlying impairments. Here, we introduce the Flu-ID Aphasia, an evidence-based tool that provides a more informative method of assessing fluency by capturing the range of behaviors that can affect the flow of speech in aphasia.

Method:
The development of the Flu-ID was based on prior evidence about factors underlying fluency (Clough & Gordon, 2020; Gordon & Clough, 2020) and clinical perceptions about the measurement of fluency (Gordon & Clough, 2022). Clinical utility is maximized by automated counting of fluency behaviors in an Excel template. Reliability is maximized by outlining thorough guidelines for transcription and coding. Eighteen narrative samples representing a range of fluency were coded independently by the authors to examine the Flu-ID's utility, reliability, and validity.

Results:
Overall reliability was very good, with point-to-point agreement of 86% between coders. Ten of the 12 dimensions showed good to excellent reliability. Validity analyses indicated that Flu-ID scores were similar to clinician ratings on some dimensions, but differed on others. Possible reasons and implications of the discrepancies are discussed, along with opportunities for improvement.

Conclusions:
The Flu-ID assesses fluency in aphasia using a consistent and comprehensive set of measures and semi-automated procedures to generate individual fluency profiles. The profiles generated in the current study illustrate how similar ratings of fluency can arise from different underlying impairments. Supplemental materials include an analysis template, extensive guidelines for transcription and coding, a completed sample, and a quick reference guide.

Abstract

With a long-term aim of empowering researchers everywhere to contribute to work on language development, we organized the First Truly Global /L+/ International Summer/ Winter School on Language Acquisition, a free 5-day virtual school for early career researchers. In this paper, we describe the school, our experience organizing it, and lessons learned. The school had a diverse organizer team, composed of 26 researchers (17 from under represented areas: Subsaharan Africa, South and Southeast Asia, and Central and South America); and a diverse volunteer team, with a total of 95 volunteers from 35 different countries, nearly half from under represented areas. This helped world-wide Page 5 of 5 promotion of the school, leading to 958 registrations from 88 different countries, with 300 registrants (based in 63 countries, 80% from under represented areas) selected to participate in the synchronous aspects of the event. The school employed asynchronous (pre-recorded lectures, which were close-captioned) and synchronous elements (e.g., discussions to place the recorded lectures into participants' context; networking events) across three time zones. A post-school questionnaire revealed that 99% of participants enjoyed taking part in the school. Not with standing these positive quantitative outcomes, qualitative comments suggested we fell short in several areas, including the geographic diversity among lecturers and greater customization of contents to the participants’ contexts. Although much remains to be done to promote inclusivity in linguistic research, we hope our school will contribute to empowering researchers to investigate and publish on language acquisition in their home languages, to eventually result in more representative theories and empirical generalizations

Abstract

Traditionally, language processing has been thought of in terms of complete processing of the input. In contrast to this, Ferreira and colleagues put forth the idea of good enough processing. The proposal was that during everyday processing, ambiguities remain unresolved, we rely on heuristics instead of full analyses, and we carry out deep processing only if we need to for the task at hand. This idea has gathered substantial traction since its conception. In the current work, I review the papers that have tested the three key claims of good enough processing: ambiguities remain unresolved and underspecified, we use heuristics to parse sentences, and deep processing is only carried out if required by the task. I find mixed evidence for these claims and conclude with an appeal to further refinement of the claims and predictions of the theory.

Abstract

Across the animal kingdom, neural responses in the auditory cortex are suppressed during vocalization, and humans are no exception. A common hypothesis is that suppression increases sensitivity to auditory feedback, enabling the detection of vocalization errors. This hypothesis has been previously confirmed in non-human primates, however a direct link between auditory suppression and sensitivity in human speech monitoring remains elusive. To address this issue, we obtained intracranial electroencephalography (iEEG) recordings from 35 neurosurgical participants during speech production. We first characterized the detailed topography of auditory suppression, which varied across superior temporal gyrus (STG). Next, we performed a delayed auditory feedback (DAF) task to determine whether the suppressed sites were also sensitive to auditory feedback alterations. Indeed, overlapping sites showed enhanced responses to feedback, indicating sensitivity. Importantly, there was a strong correlation between the degree of auditory suppression and feedback sensitivity, suggesting suppression might be a key mechanism that underlies speech monitoring. Further, we found that when participants produced speech with simultaneous auditory feedback, posterior STG was selectively activated if participants were engaged in a DAF paradigm, suggesting that increased attentional load can modulate auditory feedback sensitivity.

Abstract

Background: Despite a pervasive cortico-centric view in cognitive neuroscience, subcortical structures including the thalamus have been shown to be increasingly involved in higher cognitive functions. Previous structural and functional imaging studies demonstrated cortico-thalamo-cortical loops which may support various cognitive functions including language. However, large-scale functional connectivity of the thalamus during language tasks has not been examined before. Methods: The present study employed meta-analytic connectivity modeling to identify language-related coactivation patterns of the left and right thalami. The left and right thalami were used as regions of interest to search the BrainMap functional database for neuroimaging experiments with healthy participants reporting language-related activations in each region of interest. Activation likelihood estimation analyses were then carried out on the foci extracted from the identified studies to estimate functional convergence for each thalamus. A functional decoding analysis based on the same database was conducted to characterize thalamic contributions to different language functions. Results: The results revealed bilateral frontotemporal and bilateral subcortical (basal ganglia) coactivation patterns for both the left and right thalami, and also right cerebellar coactivations for the left thalamus, during language processing. In light of previous empirical studies and theoretical frameworks, the present connectivity and functional decoding findings suggest that cortico-subcortical-cerebellar-cortical loops modulate and fine-tune information transfer within the bilateral frontotemporal cortices during language processing, especially during production and semantic operations, but also other language (e.g., syntax, phonology) and cognitive operations (e.g., attention, cognitive control). Conclusion: The current findings show that the language-relevant network extends beyond the classical left perisylvian cortices and spans bilateral cortical, bilateral subcortical (bilateral thalamus, bilateral basal ganglia) and right cerebellar regions.

Abstract

Research on language evolution is an established subject area yet permeated by terminological controversies about which topics should be considered pertinent to the field and which not. By consequence, scholars focusing on language evolution struggle in providing precise demarcations of the discipline, where even the very central notions of evolution and language are elusive. We aimed at providing a data-driven characterisation of language evolution as a field of research by relying on quantitative analysis of data drawn from 697 reviews on 255 submissions from the Joint Conference on Language Evolution 2022 (Kanazawa, Japan). Our results delineate a field characterized by a core of main research topics such as iconicity, sign language, multimodality. Despite being explored within the framework of language evolution research, only very recently these topics became popular in linguistics. As a result, language evolution has the potential to emerge as a forefront of linguistic research, bringing innovation to the study of language. We also see the emergence of more recent topics like rhythm, music, and vocal learning. Furthermore, the community identifies cognitive science, primatology, archaeology, palaeoanthropology, and genetics as key areas, encouraging empirical rather than theoretical work. With new themes, models, and methodologies emerging, our results depict an intrinsically multidisciplinary and evolving research field, likely adapting as language itself.

Abstract

Early word learning involves mapping individual words to their meanings and building organized semantic representations among words. Previous corpus-based studies (e.g., using text from websites, newspapers, child-directed speech corpora) demonstrated that linguistic information such as word co-occurrence alone is sufficient to build semantically organized word knowledge. The present study explored two new research directions to advance understanding of how infants acquire semantically organized word knowledge. First, infants in the real world hear words surrounded by contextual information. Going beyond inferring semantic knowledge merely from language input, we examined the role of extra-linguistic contextual information in learning semantic knowledge. Second, previous research relies on large amounts of linguistic data to demonstrate in-principle learning, which is unrealistic compared with the input children receive. Here, we showed that incorporating extra-linguistic information provides an efficient mechanism through which semantic knowledge can be acquired with a small amount of data infants perceive in everyday learning contexts, such as toy play.

Abstract

Changes in the dynamics of chromatin state that control spatiotemporal gene expression patterns are crucial during brain development. CHD3 is a chromatin remodeler that is highly expressed during neurogenesis and that functions as a core member of the NuRD complex, a large multiprotein complex mediating chromatin state. Genetic disruptions in CHD3 have been implicated in a neurodevelopmental disorder characterized by intellectual disability, macrocephaly and severe speech deficits. To study the roles of CHD3 during early human brain development, we generated induced pluripotent stem cells with heterozygous and homozygous loss-of-function mutations, differentiated them into unguided neural organoids and cortical neurons, and analyzed these by immunohistochemistry, bulk RNA-, single-cell RNA-, and ChIP-sequencing. Loss of CHD3 expression had no detectable effects on early neuroepithelium formation and organoid growth, nor did it significantly affect cell type composition or neuronal differentiation speed. Instead, upon loss of CHD3, we observed dysregulation of genes related to axon guidance and synapse development across all datasets, identifying a novel role for the protein as a regulator that facilitates neurogenesis, in particular neuronal maturation. Our results based on genetically engineered knockout organoids pave the way for future studies modeling the neurobiological pathways affected in CHD3-related disorder.

Abstract

From a brain's-eye-view, when a stimulus occurs and what it is are interrelated aspects of interpreting the perceptual world. Yet in practice, the putative perceptual inferences about sensory content and timing are often dichotomized and not investigated as an integrated process. We here argue that neural temporal dynamics can influence what is perceived, and in turn, stimulus content can influence the time at which perception is achieved. This computational principle results from the highly interdependent relationship of what and when in the environment. Both brain processes and perceptual events display strong temporal variability that is not always modeled; we argue that understanding—and, minimally, modeling—this temporal variability is key for theories of how the brain generates unified and consistent neural representations and that we ignore temporal variability in our analysis practice at the peril of both data interpretation and theory-building. Here, we review what and when interactions in the brain, demonstrate via simulations how temporal variability can result in misguided interpretations and conclusions, and outline how to integrate and synthesize what and when in theories and models of brain computation.

Abstract

Unilateral anterior disc displacement (uADD) has been shown to affect the contralateral joints qualitatively. This study aims to assess the quantitative T2 values of the articular disc and retrodiscal tissue of patients with uADD at 1.5 Tesla (T). The study included 65 uADD patients and 17 volunteers. The regions of interest on T2 maps were evaluated. The affected joints demonstrated significantly higher articular disc T2 values (31.5 ± 3.8 ms) than those of the unaffected joints (28.9 ± 4.5 ms) (P < 0.001). For retrodiscal tissue, T2 values of the unaffected (37.8 ± 5.8 ms) and affected joints (41.6 ± 7.1 ms) were significantly longer than those of normal volunteers (34.4 ± 3.2 ms) (P < 0.001). Furthermore, uADD without reduction (WOR) joints (43.3 ± 6.8 ms) showed statistically higher T2 values than the unaffected joints of both uADD with reduction (WR) (33.9 ± 3.8 ms) and uADDWOR (38.9 ± 5.8 ms), and the affected joints of uADDWR (35.8 ± 4.4 ms). The mean T2 value of the unaffected joints of uADDWOR was significantly longer than that of healthy volunteers (P < 0.001). These results provided quantitative evidence for the influence of the affected joints on the contralateral joints.