241 research outputs found

    ERPs and task effects in the auditory processing of gender agreement and semantics in French

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    We investigated task effects on violation ERP responses to Noun-Adjective gender mismatches and lexical/conceptual semantic mismatches in a combined auditory/visual paradigm in French. Participants listened to sentences while viewing pictures of objects. This paradigm was designed to investigate language processing in special populations (e.g., children) who may not be able to read or to provide stable behavioral judgment data. Our main goal was to determine how ERP responses to our target violations might differ depending on whether participants performed a judgment task (Task) versus listening for comprehension (No-Task). Characterizing the influence of the presence versus absence of judgment tasks on violation ERP responses allows us to meaningfully interpret data obtained using this paradigm without a behavioral task and relate them to judgment-based paradigms in the ERP literature. We replicated previously observed ERP patterns for semantic and gender mismatches, and found that the task especially affected the later P600 component

    Merge over move and the Extended Projection Principle: MOM and the EPP Revisited

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    A class of proposals are examined that aim to avoid problems that arise in various instantiations of the ‘Merge over Move’ (MOM) cost-ofoperation distinction. It is concluded that while the mechanisms introduced there exhibit independently interesting features, they subtract substantially from the interest of the MOM economy of derivation explanations. The removal of an assumption will then be considered that makes the core cases involving there-constructions a problem to begin with: that non-finite T must host a specifier position (checking an EPP/D-feature). Denying the existence of such features removes the problem that the MOM distinction was introduced to solve, allowing the core cases of associate-movement vs. expletive-insertion to arise as a case of true optionality. Consequences for other phenomena are examined and the proposal is found to be consistent with much recent research investigating these phenomena.En este trabajo se examina una serie de propuestas destinadas a evitar problemas relacionados con varios casos de la distinción Ensamble sobre Movimiento (EsM) tomando como base el coste de la operación. Se concluye que mientras que los mecanismos introducidos en estas propuestas muestran rasgos que pueden ser interesantes de manera independiente, estos mismos se apartan sustancialmente del interés de las explicaciones derivacionales del marco EsM, basado en la economía. Será entonces cuando se considerará la eliminación de una asunción que convierta los casos básicos que implican construcciones-there en un problema con el que empezar: que el T no-finito ha de contener una posición de especificador (para cotejar un rasgo PPE/D). Negar la existencia de dichos rasgos elimina el problema para el que la distinción EsM se introdujo, permitiendo que los casos esenciales de movimiento del asociado frente a la inserción directa del expletivo se conviertan en un caso de verdadera opcionalidad. Se examinan consecuencias para otros fenómenos y se concluye que la propuesta es compatible con gran parte de las investigaciones recientes que estudian estos fenómenos.É analisada uma classe de propostas que procuram evitar problemas que emergem em v{rias instanciações da distinção de ‘Merge sobre Move’ (MOM). Conclui-se que, enquanto os mecanismos aí introduzidos exibem independentemente propriedades interessantes, eles subtraem substancialmente ao interesse das explicações da economia de derivação de MOM. A remoção de uma assunção será assim considerada, aquela que faz com que os casos centrais envolvendo construções com there constituam um problema: T não-finito deve abrigar uma posição Spec (satisfazendo uma propriedade do PPE/D). Negar a existência de tais propriedades remove o problema que a distinção MOM procurou resolver, permitindo aos casos centrais de movimento-associado vs inserção de expletivo emergir como um caso de verdadeira opcionalidade. São analisadas consequências para outros fenómenos e a proposta demonstra ser consistente com muita da investigação recente sobre os fenómenos

    The temporal dynamics of inflected word recognition: a masked ERP priming study of French verbs

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    Morphological aspects of human language processing have been suggested by some to be reducible to the combination of orthographic and semantic effects, while others propose that morphological structure is represented separately from semantics and orthography and involves distinct neuro-cognitive processing mechanisms. Here we used event-related brain potentials (ERPs) to investigate semantic, morphological and formal (orthographic) processing conjointly in a masked priming paradigm. We directly compared morphological to both semantic and formal/orthographic priming (shared letters) on verbs. Masked priming was used to reduce strategic effects related to prime perception and to suppress semantic priming effects. The three types of priming led to distinct ERP and behavioural patterns: semantic priming was not found, while formal and morphological priming resulted in diverging ERP patterns. These results are consistent with models of lexical processing that make reference to morphological structure. We discuss how they fit in with the existing literature and how unresolved issues could be addressed in further studies

    The priming of priming : Evidence that the N400 reflects context-dependent post-retrieval word integration in working memory

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    Which cognitive processes are reflected by the N400 in ERPs is still controversial. Various recent articles(Lau et al., 2008; Brouwer et al., 2012) have revived the idea that only lexical pre-activation processes(such as automatic spreading activation, ASA) are strongly supported, while post-lexical integrative pro-cesses are not. Challenging this view, the present ERP study replicates a behavioral study by McKoon andRatcliff (1995) who demonstrated that a prime-target pair such as finger − hand shows stronger primingwhen a majority of other pairs in the list share the analogous semantic relationship (here: part-whole),even at short stimulus onset asynchronies (250 ms). We created lists with four different types of semanticrelationship (synonyms, part-whole, category-member, and opposites) and compared priming for pairsin a consistent list with those in an inconsistent list as well as unrelated items. Highly significant N400reductions were found for both relatedness priming (unrelated vs. inconsistent) and relational priming(inconsistent vs. consistent). These data are taken as strong evidence that N400 priming effects are notexclusively carried by ASA-like mechanisms during lexical retrieval but also include post-lexical inte-gration in working memory. We link the present findings to a neurocomputational model for relationalreasoning (Knowlton et al., 2012) and to recent discussions of context-dependent conceptual activations(Yee and Thompson-Schill, 2016)

    Properties of Succinate Oxidation in Tomato Fruit Mitochondria

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    Environments for Magnetic Field Amplification by Cosmic Rays

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    We consider a recently discovered class of instabilities, driven by cosmic ray streaming, in a variety of environments. We show that although these instabilities have been discussed primarily in the context of supernova driven interstellar shocks, they can also operate in the intergalactic medium and in galaxies with weak magnetic fields, where, as a strong source of helical magnetic fluctuations, they could contribute to the overall evolution of the magnetic field. Within the Milky Way, these instabilities are strongest in warm ionized gas, and appear to be weak in hot, low density gas unless the injection efficiency of cosmic rays is very high.Comment: 9 pages, 8 figures; Accepted to Ap

    Rayleigh-Taylor Instabilities in Young Supernova Remnants Undergoing Efficient Particle Acceleration

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    We employ hydrodynamic simulations to study the effects of high shock compression ratios, as expected for fast shocks with efficient particle acceleration, on the convective instability of driven waves in supernova remnants. We find that the instability itself does not depend significantly on the compression ratio, but because the width of the interaction region between the forward and reverse shocks can shrink significantly with increasing shock compression, we find that convective instabilities can reach all the way to the forward shock front if compression ratios are high enough.Comment: Submitted to The Astrophysical Journa

    A Common Network of Functional Areas for Attention and Eye Movements

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    AbstractFunctional magnetic resonance imaging (fMRI) and surface-based representations of brain activity were used to compare the functional anatomy of two tasks, one involving covert shifts of attention to peripheral visual stimuli, the other involving both attentional and saccadic shifts to the same stimuli. Overlapping regional networks in parietal, frontal, and temporal lobes were active in both tasks. This anatomical overlap is consistent with the hypothesis that attentional and oculomotor processes are tightly integrated at the neural level

    Group versus Individualised Minimum Velocity Thresholds in the Prediction of Maximal Strength in Trained Female Athletes

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    This study examined the accuracy of di erent velocity-based methods in the prediction of bench press and squat one-repetition maximum (1RM) in female athletes. Seventeen trained females (age 17.8 1.3 years) performed an incremental loading test to 1RM on bench press and squat with the mean velocity being recorded. The 1RM was estimated from the load–velocity relationship using the multiple- (8 loads) and two-point (2 loads) methods and group and individual minimum velocity thresholds (MVT). No significant e ect of method, MVT or interaction was observed for the two exercises (p > 0.05). For bench press and squat, all prediction methods demonstrated very large to nearly perfect correlations with respect to the actual 1RM (r range = 0.76 to 0.97). The absolute error (range = 2.1 to 3.8 kg) for bench press demonstrated low errors that were independent of the method and MVT used. For squat, the favorable group MVT errors for the multiple- and two-point methods (absolute error = 7.8 and 9.7 kg, respectively) were greater than the individual MVT errors (absolute error = 4.9 and 6.3 kg, respectively). The 1RM can be accurately predicted from the load–velocity relationship in trained females, with the two-point method o ering a quick and less fatiguing alternative to the multiple-point method
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