Inter-hemispheric asymmetries in STS and AF and the structural relationship between the two

Superior temporal sulcus (STS), a grey matter structure, and arcuate fasciculus (AF), a white matter tract, have several characteristics in common. They are structurally asymmetric across brain hemispheres, they seem to hold overlapping cognitive functions, and they are located in close proximity to each other. The purpose of the current study is to explore the structural relationship between STS and AF. Two hypotheses are stated. First, it is hypothesised that the depth asymmetry in STS will correlate negatively with AF volume tract asymmetry, as they are assumed to compete for the same limited space in the brain. The second hypothesis is based on evidence suggesting that STS and AF are involved in language processing. It is hypothesised that a positive correlation between STS asymmetry and AF asymmetry will be found for variables assumed relevant for language processing. To address this, T1-weigted anatomical MR images and diffusion-weighted MR images were acquired from twenty participants. The current findings do not support the hypotheses. Negative correlations were found between left AF volume and left STS depth and between left AF volume and left STS length. In the right hemisphere, positive correlations were found between right AF volume and right STS and between right AF volume and right STS length. In light of this, two new hypotheses are suggested. In the right hemisphere, STS and AF may share social cognitive functionality. In the left hemisphere, a language related compensation mechanism may underlie the correlations.Superior temporal sulucs (STS), ein gråsubstans-struktur, og arcuate fasciculus (AF), ein kvitsubstans-fiberbunt, har fleire eigenskapar til felles. Dei er strukturelt asymmetriske på tvers av hjernehemisfærane, dei synest å ha overlappande kognitive funksjonar, og dei ligg i nærleiken av kvarandre. Føremålet med denne studien er å utforske det strukturelle forholdet mellom STS og AF. To hypotesar er føreslått. Først, ein antar at den djupneasymmetrien i STS korrelerer negativt med volumasymmetrien i AF fordi desse tenkast å konkurrere om overlappande områder i hjernen. Den andre hypotesen er basert på forsking som indikerer at både STS og AF er involvert i språkprosessering. Ein antar å finne ein positiv korrelasjon mellom STS-asymmetri og AF-asymmetri for variablar antas å vere relevante for språkprosessering. For å adressere dette vart det innhenta T1-vekta anatomiske MR-bilete og diffusjonsvekta MR-bilete frå tjue deltakarar. Resultatet av studien gir ikkje støtte til hypotesane. Ein finn negative korrelasjonar mellom venstre AF volum og venstre STS djupn og venstre AF volum og STS lengde. I høgre hemisfære finner ein at høgre AF volum korrelerer positive med STS djupn og høgre AF volum korrelerer positivt med høgre STS lengde. I lys av dette, foreslås to nye hypotesar. I høgre hemisfære antas STS og AF å dele sosialkognitiv funksjonalitet. I venstre hemisfære antas ein språkrelatert kompenasjonsmekanisme å ligge til grunn for korrelasjonen.PROPSY317PRPSY

A SYSTEMATIC REVIEW OF COLLABORATIVE WRITING IMPLEMENTATION IN K-12 SECOND LANGUAGE CLASSROOMS

In recognizing that writing is a social act, collaborative writing has received increased attention in second language (L2) classrooms. A large body of research literature explores the varied ways of L2 collaborative writing development in tertiary education settings, but relatively little is known about the implementation of collaborative writing in K-12 classrooms. In this study, the authors systematically reviewed a total of 12 peer-reviewed empirical studies on the use of collaborative writing in K-12 L2 classrooms to provide new insights into this particular context. Comprehensive analysis has been conducted, including the research context, writing task, mode of interaction, research focus, and assessment. The findings reveal that the majority of the selected studies have involved K-12 students learning English as a target language with diverse writing tasks. Three different collaborative writing approaches have been implemented in K-12 classrooms of L2, including face-to-face, online, and a blend of both styles. The main research foci of the reviewed literature are writing processes, writing outcomes, and collaborative writing affordances. Diverse assessment methods are utilized to measure L2 writers’ writing process and product. Drawing on the analyses, the researchers discuss the pedagogical implications and research strands that deserve further examination

Evolution of Social Networks Among American Female Adolescents

This study delves into the evolution of social networks incorporating both elements of Rational Choice Theory and Feminist Theory inside a Social Network analysis. Simulated data was generated by modeling American female adolescents as an instantiation of a more general set of theoretical ideas about the formation of gendered relational patterns. This study uses the methodology of Computer Simulation to explore micro to macro mechanisms and account for how individual social actions aggregate to generate macro-level network structures. This research examines generative mechanisms and explores under what conditions some characteristics of gendered network structures emerge and are maintained through time. Three AVI files (movies of simulation demos) and a JAR (Java ARchive) of the JAVA code are also included

Consumer policy - a network/political economy perspective : an application of the new macro-relational consumer policy framework to study the evolutionary dynamics of the policy community for the Electronic Fund Transfer System (EFTS) consumer issue in Canada

This thesis argued that-sole reliance by government on the micro-economic paradigm. as the rationale for intervening in the marketplace results in too narrow an approach to consumer policy and a lack of appreciation for the dynamic and relational aspects of the consumer policy process. An integration of select constructs from the political economy and network paradigms contributed to the development of a macro-relational consumer policy framework. The network approach provides a relational perspective while the political economy paradigm provides a macro approach to widening consumer policy theory. Together, they offer a macro-relational perspective to compliment the micro-economic approach. The investigator suggests that the computerization of the Canadian payment system represents a change in the technological sphere of the macro policy environment. This change challenges the marketplace interests of the consumer policy network constituents (secondary policy environment). The stakeholders affected by this change coalesce into a policy community to balance respective interests. This primary policy environment, evolutionary in nature (internal policy activity, then dyadic, multidyadic, and triadic), will exhibit varying patterns of stakeholder interaction, relationship development and network dynamics. Propositions developed, to explain the evolutionary dynamics of the policy community guided the content analysis, the case study and the network analysis. Relational data (matrices and graphs) profiled the chronological maps of the relationships of the aggregate, constituent and dyadic sets of stakeholders. A multi-layered network analysis revealed an evolutionary process and a policy community which varied on several interaction dimensions (frequency, directedness, durability, role perception, intensity) and network dimensions (size, density, connectedness, cohesiveness, knittedness, stability). To mirror parallel initiatives in complimentary disciplines, stakeholders and future macro-relational consumer policy researchers are challenged to embrace the powerful network/political economy perspective to profit from stimulating theoretical and pragmatic insights into the complex, dynamic consumer policy process.This thesis argued that-sole reliance by government on the micro-economic paradigm. as the rationale for intervening in the marketplace results in too narrow an approach to consumer policy and a lack of appreciation for the dynamic and relational aspects of the consumer policy process. An integration of select constructs from the political economy and network paradigms contributed to the development of a macro-relational consumer policy framework. The network approach provides a relational perspective while the political economy paradigm provides a macro approach to widening consumer policy theory. Together, they offer a macro-relational perspective to compliment the micro-economic approach. The investigator suggests that the computerization of the Canadian payment system represents a change in the technological sphere of the macro policy environment. This change challenges the marketplace interests of the consumer policy network constituents (secondary policy environment). The stakeholders affected by this change coalesce into a policy community to balance respective interests. This primary policy environment, evolutionary in nature (internal policy activity, then dyadic, multidyadic, and triadic), will exhibit varying patterns of stakeholder interaction, relationship development and network dynamics. Propositions developed, to explain the evolutionary dynamics of the policy community guided the content analysis, the case study and the network analysis. Relational data (matrices and graphs) profiled the chronological maps of the relationships of the aggregate, constituent and dyadic sets of stakeholders. A multi-layered network analysis revealed an evolutionary process and a policy community which varied on several interaction dimensions (frequency, directedness, durability, role perception, intensity) and network dimensions (size, density, connectedness, cohesiveness, knittedness, stability). To mirror parallel initiatives in complimentary disciplines, stakeholders and future macro-relational consumer policy researchers are challenged to embrace the powerful network/political economy perspective to profit from stimulating theoretical and pragmatic insights into the complex, dynamic consumer policy process

Network approaches to understanding the functional effects of focal brain lesions

Complex network models of functional connectivity have emerged as a paradigm shift in brain mapping over the past decade. Despite significant attention within the neuroimaging and cognitive neuroscience communities, these approaches have hitherto not been extensively explored in neurosurgery. The aim of this thesis is to investigate how the field of connectomics can contribute to understanding the effects of focal brain lesions and to functional brain mapping in neurosurgery. This datasets for this thesis include a clinical population with focal brain tumours and a cohort focused on healthy adolescent brain development. Multiple network analyses of increasing complexity are performed based upon resting state functional MRI. In patients with focal brain tumours, the full complement of resting state networks were apparent, while also suggesting putative patterns of network plasticity. Connectome analysis was able to identify potential signatures of node robustness and connections at risk that could be used to individually plan surgery. Focal lesions induced the formation of new hubs while down regulating previously established hubs. Overall these data are consistent with a dynamic rather than a static response to the presence of focal lesions. Adolescent brain development demonstrated discrete dynamics with distinct gender specific and age-gender interactions. Network architecture also became more robust, particularly to random removal of nodes and edges. Overall these data provide evidence for the early vulnerability rather than enhanced plasticity of brain networks. In summary, this thesis presents a combined analysis of pathological and healthy development datasets focused on understanding the functional effects of focal brain lesions at a network level. The coda serves as an introduction to a forthcoming study, known as Connectomics and Electrical Stimulation for Augmenting Resection (CAESAR), which is an evolution of the results and methods herein.MGH is funded by the Wellcome Trust Neuroscience in Psychiatry Network with additional support from the National Institute for Health Research Cambridge Biomedical Research Centre

A Neurobiologically Constrained Model

Understanding the meaning of words and its relationship with the outside world involves higher cognitive processes unique of the human brain. Despite many decades of research on the neural substrates of semantic processing, a consensus about the functions and components of the semantic system has not been reached among cognitive neuroscientists. This issue is mainly influenced by two sets of neurocognitive empirical findings that have shown (i) the existence of several regions acting as ’semantic hubs’, where the meaning of all types of words is processed and (ii) the presence of other cortical regions specialised for the processing of specific semantic word categories, such as animals, tools, or actions. Further evidence on semantic meaning processing comes from neuroimaging and transcranial magnetic stimulation studies in visually deprived population that acquires semantic knowledge through non-sensory modalities. These studies have documented massive neural changes in the visual system that is in turn recruited for linguistic and semantic processing. On this basis, this dissertation investigates the neurobiological mechanism that enables humans to acquire, store and processes linguistics meaning by means of a neurobiologically constrained neural network and offers an answer to the following hotly debated questions: Why both semantic hubs and modality-specific regions are involved in semantic meaning processing in the brain? Which biological principles are critical for the emergence of semantics at the microstructural neural level and how is the semantic system implemented under deprived conditions, in particular in congenitally blind people? First, a neural network model closely replicating the anatomical and physiological features of the human cortex was designed. At the micro level, the network was composed of 15,000 artificial neurons; at the large-scale level, there were 12 areas representing the frontal, temporal, and occipital lobes relevant for linguistic and semantic processing. The connectivity structure linking the different cortical areas was purely based on neuroanatomical evidence. Two models were used, each simulating the same set of cortical regions but at different level of details: one adopted a simple connectivity structure with a mean-field approach (i.e. graded-response neurons), and the other used a fully connected model with adaptation-based spiking cells. Second, the networks were used to simulate the process of learning semantic relationships between word-forms, specific object perceptions, and motor movements of the own body in deprived and undeprived visual condition. As a result of Hebbian correlated learning, distributed word-related cell assembly circuits spontaneously emerged across the different cortical semantic areas exhibiting different topographical distribution. Third, the network was reactivated with the learned auditory patterns (simulating word recognition processes) to investigate the temporal dynamics of cortical semantic activation and compare them with real brain responses. In summary, the findings of the present work demonstrate that meaningful linguistic units are represented in the brain in the form of cell assemblies that are distributed over both semantic hubs and category-specific regions spontaneously emerged through the mutual interaction of a single set of biological mechanisms acting within specific neuroanatomical structures. These biological principles acting together also offer an explanation of the mechanisms underlying massive neural changes in the visual cortex for language processing caused by blindness. The present work is a first step in better understanding the building blocks of language and semantic processing in sighted and blind populations by translating biological principles that govern human cognition into precise mathematical neural networks of the human brain.Um die Bedeutung von Wörtern und ihre Beziehung zur Außenwelt zu verstehen, müssen die kognitiven Prozesse betrachtet werden, die einzigartig für das menschliche Gehirn sind. Trotz jahrzehntelanger Forschungen an den neuronalen Substraten der semantischen Verarbeitung im menschlichen Gehirn wurde bisher kein Konsens über die Funktionen und Komponenten des semantischen Systems in den kognitiven Neurowissenschaftlern erreicht. Dieses Problem gründet darin, dass neurokognitive empirische Studien zumeist zu zwei Endergebnissen kamen: (i) der Existenz von mehrere Regionen, die als ‘semantische Hubs’ fungieren, in denen die Bedeutung aller Wortarten verarbeitet wird, und (ii) dem Vorhandensein weiterer kortikaler Regionen, die auf die Verarbeitung spezifischer semantischer Kategorien wie Tiere, Werkzeuge oder Aktionswörtern spezialisiert sind. Ein weiterer Beweis für die Verarbeitung semantischer Bedeutungen lässt sich aus Bildgebungsstudien und Studien mit transkranialer Magnetstimulation an visuell benachteiligten Probanden entnehmen, die die linguistische Bedeutung nicht durch sensorische Modalitäten erwerben. Diese Studien konnten massive neuronale Veränderungen im visuellen System dokumentieren, die wiederum für die sprachliche und semantische Verarbeitung verwendet werden. Die vorliegende Dissertation untersucht mittels eines biologischen neuronalen Netzwerkes jene kognitiven Prozesse, die es Menschen ermöglichen, linguistische Bedeutungen in der täglichen Kommunikation zu erfassen, zu speichern und zu verarbeiten. Sie schlägt Antworten auf die folgenden neurowissenschaftlich heiß diskutierten Fragen vor: Warum sind sowohl semantische Hubs als auch modalitätsspezifische Regionen relevant für die sprachliche und semantische Informationsverarbeitung im Gehirn? Welche biologischen Prinzipien sind von entscheidender Bedeutung für die Entstehung von Semantik auf mikrostruktureller neuronaler Ebene? Und Wie ist das semantische System unter benachteiligten Bedingungen repräsentiert? Zunächst wurde ein neuronales Netzwerkmodell implementiert, das die anatomischen und physiologischen Merkmale des menschlichen Kortex präzise widerspiegelt. Auf der Mikroebene besteht das Netzwerkmodel aus 15.000 künstlichen Neuronen, auf der Großebene aus 12 Arealen der Frontal-, Temporal- und Okzipitallappen, die für die sprachliche und semantische Verarbeitung relevant sind. Die Verbindungsstruktur zwischen den verschiedenen kortikalen Arealen wurde rein auf Grundlage von neuroanatomischen Befunden implementiert. Zwei Modelle wurden verwendet, die jeweils die gleichen kortikalen Regionen simulierten, allerdings in verschiedenen Varianten: Das erste Modell ging von einer einfachen Konnektivitätsstruktur mit einem Mean-field Ansatz (graded-response neurons) aus, während das zweite einen vollständig verbundenen Aufbau mit adaptionsbasierten Spiking-Zellen (Aktionspotential) verwendete. Anschließend dienten die neuronalen Netzwerke dazu, den Lernprozess der semantischen Verlinkung zwischen Wortformen, bestimmten Objektwahrnehmungen und motorischen Bewegungen des eigenen Körpers zu simulieren, sowohl in gesundem als auch in benachteiligtem Sehzustand. Als Ergebnis des Hebbschen Korrelationslernens traten spontan verteilte Neuronenverbindungen (cell assemblies) in den verschiedenen kortikalen semantischen Bereichen auf, die unterschiedliche topografische Verteilungen zeigten. Zuletzt wurde das Netzwerkmodell mit den erlernten auditorischen Mustern reaktiviert (Worterkennungsprozesse), um die zeitliche Dynamik kortikaler semantischer Aktivierung zu untersuchen und sie mit realen Gehirnantworten zu vergleichen. Die vorliegende Arbeit kam zu folgenden Ergebnissen: Die neuronale Repräsentation linguistischer Bedeutung wird im Gehirn in Form von cell assemblies dargestellt, welche über semantische Hubs und modalitätsspezifische Regionen verteilt sind. Diese entstehen spontan durch die Interaktion einer Reihe von biologischen Mechanismen, die innerhalb spezifischer neuroanatomischer Strukturen wirken. Das Zusammenwirken dieser biologischen Prinzipien bietet zusätzlich eine Erklärung für jene Faktoren, die für die massiven neuronalen Veränderungen in der sprachlichen und semantischen Netzwerke bei Blindheit verantwortlich sind. Die in dieser Dissertation dokumentierten Studien sind ein erster Schritt in Richtung eines besseren Verständnisses der sprachlichen und semantischen Informationsverarbeitung bei sehenden und blinden Menschen, basierend auf einer Übersetzung der biologischen Prinzipien der menschlichen Kognition in präzise mathematische neuronale Netzwerke des menschlichen Gehirns

Diteng tsa ditlhopha tsa maina a Bantu: ntlhathakanelo e le mo Setswanang : “The semantics of Bandu noun classes: a focus on Setswana

The present study investigated the semantic classification of the Setswana noun class system. This enquiry falls under the broad area of the noun classification system in Bantu languages, psycholinguistics and lexicogrpahy. Specifically it explores the basis of noun classification in Setswana making indications that Setswana noun classification is based on a partial semantic classification. Data for the study was drawn from the Setswana Oxford Dictionary. Sixty Setswana nouns, from class 1, 3, 5, and 7, were selected and analysed and then grouped into semantic categories (i.e., PERSON, DEROGATION, TRANSPORATION and so forth). The study adopted Kgukutli’s (1994) semantic classification in performing the dictionary analysis. The rest of the data was drawn from the intuitions of thirty-nine contemporary speakers of Setswana, with the aid of a linguistic test which was fashioned according to Selvik’s (2001) psycholinguistic test. The language test required participants to match the predetermined Setswana definitions with hypothetical Setswana nouns with selected class prefixes attached to them. The results from the empirical study showed that speakers were associating prefixes to certain semantic values, suggesting that each noun class had specific semantic content that was unique to that class. The semantic categories created through the dictionary analysis were then compared to those given by the thirty-nine Setswana speakers, to analyse whether there were any similaritires in the semantic classification of the noun classes. The findings of the dictionary analysis and linguistic test revealed that there were certain semantic characteristics that each class was associated with that seemed to be unique to the class. However, there were various semantic overlaps in the semantic categories associated with the different noun classes, which brings into question whether a semantic classification is viable in the classing of nouns. The study suggests that prior classification of Setswana nouns are not precise enough and that additional semantic categories are needed to offer a more precise classification of nouns in this language

"Nec tecum nec sine te" : Language-Music Interplays in Musical Responses to Samuel Beckett

Intermediality is rarely a one-way street: Throughout his career, Samuel Beckett employed a variety of modes of expression and media in his works, and – vice versa – it is partly owing to the strong role played by music in his works that Samuel Beckett's works figure so prominently in compositional history from 1930 to the present day. In fact, with more than 250 Beckett-based compositions of different genres and styles and from various countries responding to virtually the entire Beckettian œuvre, Beckett's poems, plays and prose have exerted an influence on composers unequalled by those of any other 20th-century author. This study shows that Beckett's double-coded language, sounds and images have served as a blueprint for crossing medial and social gaps in favor of a de-hierarchization of both the author-audience relationship and the intermedial interplay. As a result of this paradigm shift toward more participatory artistic modes and toward a postmodern "radical pluralization" (Wolfgang Welsch) of meaning and expressive vehicles, Beckett regarded music as an equal interlocutor of language and, vice versa, composers have become more receptive to entirely new modes of text-setting. "Nec tecum nec sine te," a Latin phrase by Ovid cited by Beckett to describe the double-edged relationship between Hamm and Clov from Endgame – interdependent yet noncommittal – equally applies to the text-music interplays portrayed in the present work