Papers Reading

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[edit] Reading Papers

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    Abstract.
    Posted by: YOU today


Keith J. Duncan1, Chotiga Pattamadilok1,2, and Joseph T. Devlin1
jocn.2009.21207
University College London, London, UK 2Fonds de la Recherche Scientifique—FNRS and Université Libre de Bruxelles, Belgium
    The debate regarding the role of ventral occipito-temporal cortex (vOTC) in visual word recognition arises, in part, from difficulty delineating the functional contributions of vOTC as separate from other areas of the reading network. Here, we investigated the feasibility of using transcranial magnetic stimulation (TMS) to interfere with vOTC processing in order to explore its specific contributions to visual word recognition. Three visual lexical decision experiments were conducted using neuronavigated TMS. The first demonstrated that repetitive stimulation of vOTC successfully slowed word, but not nonword, responses. The second confirmed and extended these findings by demonstrating the effect was specific to vOTC and not present in the adjacent lateral occipital complex. The final experiment used paired-pulse TMS to investigate the time course of vOTC processing for words and revealed activation starting as early as 80–120 msec poststimulus onset—significantly earlier than that expected based on electrophysiological and magnetoencephalography studies. Taken together, these results clearly indicate that TMS can be successfully used to stimulate parts of vOTC previously believed to be inaccessible and provide a new tool for systematically investigating the information processing characteristics of vOTC. In addition, the findings provide strong evidence that lexical status and frequency significantly affect vOTC processing, findings difficult to reconcile with prelexical accounts of vOTC function.
    Posted by: AMR 4/2/2009 -- Going along with the TMS stuff, here's a new one where they successfully got to pOTS. Note this is from Joe Devlin, who you'll remember is very opposed to the idea of a VWFA.


Martin Kronbichler, Johannes Klack, Fabio Richlan, Matthias Schurz, Wolfgang Staffen, Gunther Ladurner, and Heinz Wimmer
J Cogn Neurosci, Feb 2009
University of Salzburg, Austria & Paracelsus Private Medical University, Salzburg, Austria
    This functional magnetic resonance imaging study contrasted case-deviant and letter-deviant forms with familiar forms of the same phonological words (e.g., TaXi and Taksi vs. Taxi) and found that both types of deviance led to increased activation in a left occipito-temporal region, corresponding to the visual word form area (VWFA). The sensitivity of the VWFA to both types of deviance may suggest that this region represents well-known visual words not only as sequences of abstract letter identities but also includes information on the typical case-format pattern of visual words. Case-deviant items, in addition, led to increased activation in a right occipito-temporal region and in a left occipital and a left posterior occipito-temporal region, which may reflect increased demands on letter processing posed by the case-deviant forms.
    Posted by: AK 3/27/2009


Nienke van Atteveld, Elia Formisano, Rainer Goebel, and Leo Blomert
Neuron, July 2004
University of Maastricht, Faculty of Psychology and Neuroscience, Department of Cognitive Neuroscience, The Netherlands
    Most people acquire literacy skills with remarkable ease, even though the human brain is not evolutionarily adapted to this relatively new cultural phenomenon. Associations between letters and speech sounds form the basis of reading in alphabetic scripts. We investigated the functional neuroanatomy of the integration of letters and speech sounds using functional magnetic resonance imaging (fMRI). Letters and speech sounds were presented unimodally and bimodally in congruent or incongruent combinations. Analysis of single-subject data and group data aligned on the basis of individual cortical anatomy revealed that letters and speech sounds are integrated in heteromodal superior temporal cortex. Interestingly, responses to speech sounds in a modality-specific region of the early auditory cortex were modified by simultaneously presented letters. These results suggest that efficient processing of culturally defined associations between letters and speech sounds relies on neural mechanisms similar to those naturally evolved for integrating audiovisual speech.
    Posted by: AK 4/10/2009


Blau V, van Atteveldt N, Ekkebus M, Goebel R, Blomert L.
Current Biology, March 2009
University of Maastricht, Faculty of Psychology and Neuroscience, Department of Cognitive Neuroscience, The Netherlands
    Developmental dyslexia is a specific reading and spelling deficit affecting 4% to 10% of the population. Advances in understanding its origin support a core deficit in phonological processing characterized by difficulties in segmenting spoken words into their minimally discernable speech segments (speech sounds, or phonemes) and underactivation of left superior temporal cortex. A suggested but unproven hypothesis is that this phonological deficit impairs the ability to map speech sounds onto their homologous visual letters, which in turn prevents the attainment of fluent reading levels. The present functional magnetic resonance imaging (fMRI) study investigated the neural processing of letters and speech sounds in unisensory (visual, auditory) and multisensory (audiovisual congruent, audiovisual incongruent) conditions as a function of reading ability. Our data reveal that adult dyslexic readers underactivate superior temporal cortex for the integration of letters and speech sounds. This reduced audiovisual integration is directly associated with a more fundamental deficit in auditory processing of speech sounds, which in turn predicts performance on phonological tasks. The data provide a neurofunctional account of developmental dyslexia, in which phonological processing deficits are linked to reading failure through a deficit in neural integration of letters and speech sounds.
    Posted by: AK 3/27/2009


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