A copy of this work was available on the public web and has been preserved in the Wayback Machine. The capture dates from 2017; you can also visit the original URL.
The file type is
In the present fMRI study, we addressed the question as to whether motor-perceptual interactions might be involved in reading. Recognizing the letters encountered when reading is generally assumed to be a purely visual process, yet because we know how to write, we also possess a sensorimotor representation of the letters. Does simply viewing a letter suffice to activate the corresponding motor representation? To answer this question, we asked right-handed subjects first to look at and then todoi:10.1016/s1053-8119(03)00088-0 pmid:12948705 fatcat:oxglttodszbtxcbdgatrplgloi
more »... py single letters or pseudoletters. We established that the visual presentation of letters activated a part of the left premotor cortex (BA6) that was also activated when the letters were being written by the subjects. This premotor zone resembles Exner's area, which is thought to contain the motor programs necessary for producing letters. Visually presented pseudoletters, which had never been written before by the subjects, did not activate this region. These results indicate that the writing motor processes are implicitly evoked when passively observing letters. The cerebral representation of letters is therefore presumably not strictly visual, but based on a multicomponent neural network built up while learning concomitantly to read and write. One of the components might be a sensorimotor one associated with handwriting. This finding shows the existence of close functional relations between the reading and writing processes, and suggests that our reading abilities might be somehow dependent on the way we write.
et al.. Brain correlates of phonological recoding of visual symbols. NeuroImage, Elsevier, 2016, 132, pp. Abstract Learning to read involves setting up associations between meaningless visual inputs (V) and their phonological representations (P). Here, we recorded the brain signals (ERPs and fMRI) associated with phonological recoding (i.e., V-P conversion processes) in an artificial learning situation in which participants had to learn the associations between 24 unknown visual symbolsdoi:10.1016/j.neuroimage.2016.02.010 pmid:26902821 fatcat:c3hiriwjfrff3phld7y2xrfmyi
more »... e Katakana characters) and 24 arbitrary monosyllabic names. During the learning phase on Day 1, the strength of V-P associations was manipulated by varying the proportion of correct and erroneous associations displayed during a two-alternative forced choice task. Recording event related potentials (ERPs) during the learning phase allowed us to track changes in the processing of these visual symbols as a function of the strength of V-P associations. We found that, at the end of the learning phase, ERPs were linearly affected by the strength of V-P associations in a time-window starting around 200 ms post-stimulus onset on right occipital sites and ending around 345 ms on left occipital sites. On Day 2, participants had to perform a matching task during an fMRI session and the strength of these V-P associations was again used as a probe for identifying brain regions related to phonological recoding. Crucially, we found that the left fusiform gyrus was gradually affected by the strength of V-P associations suggesting that this region is involved in the brain network supporting phonological recoding processes.
., 2009 ), seems to be crucial for the instantiation of motor commands for producing letters (Longcamp, Anton, Roth, & Velay, 2003; Longcamp et al., 2014; Rapp & Dufor, 2011; Roux et al., 2009; Sugihara ... To this end we used the MarsBar SPM toolbox (Brett, Anton, Valbregue, & Poline, 2002) to define individual regions of interest at the vicinity of the localizations highlighted in the two metaanalysis ...doi:10.1016/j.cortex.2018.11.024 pmid:30640140 fatcat:zwrmvb43rner5afolzje735lp4
cortices, are not directly involved. Alternatively, in ac-1 BCN Neuroimaging Centre cord with our introspective experience of "almost feeling University of Groningen the spider crawling on our own chest," a much less 9713 AW Groningen cognitively flavored explanation would propose that the The Netherlands vision of the other person being touched might automati-2 CNRS cally be associated with an activation of the cortical Institut de Neurosciences Physiologiques network of regions normallydoi:10.1016/s0896-6273(04)00156-4 pmid:15091347 fatcat:gq3tal2fb5a7jjg7ksjyadojlm
more »... ed in our own experiet Cognitives ence of being touched. We would then understand that 13402 Marseille cedex 20 the other person is being touched through aspects of our France own experience of touch, which have been automatically 3 Centre d'Imagerie par RMN fonctionnelle activated by the visual stimulus. A testable difference CHU la Timone between these two accounts is that the somatosensory 13385 Marseille cedex 05 cortices should be systematically activated by the ob-France servation of touch in the latter but not in the former. 4 Department of Neuroscience (Physiology) Touch, though, is not restricted to the social world: 5 Department of Psychology we often witness objects touching each other. How does University of Parma our brain process the sight of two cars bumping into 43100 Parma each other? It might be that such "inanimate touch" is Italy processed by the brain in ways fundamentally different from those used to process the sight of touch occurring to another living being. In contrast, in the light of the Summary classical experiments of Heider and Simmel (1944), in which the sight of circles and triangles touching each Watching the movie scene in which a tarantula crawls other is interpreted as two people punching each other, on James Bond's chest can make us literally shiver-as one might speculate that even inanimate touch might if the spider crawled on our own chest. What neural be processed through our own experience of touch. mechanisms are responsible for this "tactile empa-This latter hypothesis would predict that the sight of thy"? The observation of the actions of others actiinanimate touch would activate parts of the observer's vates the premotor cortex normally involved in the somatosensory cortices. execution of the same actions. If a similar mechanism Evidence for the fact that the observation of other applies to the sight of touch, movies depicting touch individuals can activate some of the neural circuitries should automatically activate the somatosensory cornormally involved when we do or feel similar things tex of the observer. Here we found using fMRI that the comes from two lines of investigation. First, in humans secondary but not the primary somatosensory cortex and monkeys, performing goal-directed actions actiis activated both when the participants were touched vates a network of cortical areas including the premotor, and when they observed someone or something else motor, and posterior parietal areas. Observing or lisgetting touched by objects. The neural mechanisms tening to another individual performing those same acenabling our own sensation of touch may therefore be tions also activates the premotor and parietal cortex a window also to our understanding of touch.
Lecture Notes in Computer Science
In this paper, we present an original method that aims at parcellating the cortical surface in regions functionally meaningful, from individual anatomy. The parcellation is obtained using an anatomically constrained surface-based coordinate system from which we define a complete partition of the surface. The aim of our method is to exhibit a new way to describe the cortical surface organization, in both anatomical and functional terms. The method is described together with results applied to a functional somatotopy experiments.doi:10.1007/11866763_24 fatcat:7n5ope6n5nai3fcoctw25uabi4
Strong evidence has accumulated over the past years suggesting that orthography plays a role in spoken language processing. It is still unclear, however, whether the influence of orthography on spoken language results from a co-activation of posterior brain areas dedicated to low-level orthographic processing or whether it results from orthographic restructuring of phonological representations located in the anterior perisylvian speech network itself. To test these hypotheses, we ran a fMRIdoi:10.3389/fpsyg.2011.00378 pmid:22207859 pmcid:PMC3245630 fatcat:zlyc7h2vovbnxoauxmfgeinfby
more »... y that tapped orthographic processing in the visual and auditory modalities. As a marker for orthographic processing, we used the orthographic decision task in the visual modality and the orthographic consistency effect in the auditory modality. Results showed no specific orthographic activation neither for the visual nor the auditory modality in left posterior occipito-temporal brain areas that are thought to host the visual word form system. In contrast, specific orthographic activation was found both for the visual and auditory modalities at anterior sites belonging to the perisylvian region: the left dorsal-anterior insula and the left inferior frontal gyrus. These results are in favor of the restructuring hypothesis according to which learning to read acts like a "virus" that permanently contaminates the spoken language system. Keywords: visual word recognition, speech perception, orthographic consistency, inferior frontal gyrus, insula, visual word form system, visual word form area
Anton*, Muriel Roth*®, Bruno Nazarian’, and Jean-Luc Velay~ Abstract @ Fast and accurate visual recognition of single characters is crucial for efficient reading. ... Learning through Hand- or Typewriting Influences Visual Recognition of New Graphic Shapes: Behavioral and Functional Imaging Evidence Marieke Longcamp'”, Céline Boucard’, Jean-Claude Gilhodes’, Jean-Luc ...doi:10.1162/jocn.2008.20504 pmid:18201124 fatcat:4hjzcok5tnecfdgmg7qeo6whf4
We warmly thank Jean-Michel Viton who took the medical responsibility for the passage of the subjects in the 3T fMRI machine. ...doi:10.1016/j.neuroimage.2003.11.009 pmid:15050561 fatcat:e2d2pymfbbcjplmlww25ip2u4u
The brain areas involved in music reading were investigated using fMRI. In order to evaluate the speci¢city of these areas we compared reading music notation to reading verbal and number notations in a task that required professional pianists to play the notes (in musical and verbal notations) and the numbers displayed on a 5key keyboard. Overall, the three tasks revealed a similar pattern of activated brain areas. However, direct contrasts between the music notation and the verbal or thedoi:10.1097/00001756-200212030-00023 pmid:12488812 fatcat:mfecp3mfh5bktbekv62rkex2ca
more »... cal notation tasks also revealed speci¢c major foci of activation in the right occipito-tem-poral junction, superior parietal lobule and the intraparietal sulcus. We interpret the right occipito-temporal di¡erence as due to differences at the encoding level between notes, words and numbers. This area might be analogous to one described for words, called the visual word form area. The parietal activations are discussed in terms of visuo-motor transcoding pathways that di¡er for the three types of notations used. Finally, we present a model of music reading that can possibly explain our ¢ndings. NeuroReport 13:2285^2289
., Anton, J. L., Roth, M., & Velay, J. L. (2003) . Visual presentation of single letters activates a premotor area involved in writing. NeuroImage, 19, 1492-1500]. ... In a second step, we used MarsBar-SPM toolbox (Brett, Anton, Valbregue, & Poline, 2002) to define two regions of interest (ROI) in the left and right vPMCsup. ... In a previous neuroimaging study (Longcamp, Anton, Roth, & Velay, 2003) , we directly assessed the possibility that motoric writing skills might be automatically involved in the visual perception of alphabetical ...doi:10.1016/j.neuropsychologia.2005.01.020 pmid:16154456 fatcat:dmih4zmbhjhcjadh26rmkl4xky
Human Brain Mapping
We are grateful to Jean Claude Gilhodes, Jasmin Sadat, and Michel Habib for support on various aspects of the study. The work was performed at Lab. Neurosciences Cognitives and Centre IRMf. ...doi:10.1002/hbm.22606 pmid:25093278 fatcat:hawsdhld4nfyxmiv7x73f5bnv4
Over the last few years sunscreen products have been suspected to be harmful to corals, especially because of their putative negative impact on symbiotic microalgae housed by these cnidarians. Previous publications reported that minerals or chemical UV filters could induce the release of microalgae from corals inducing their bleaching. The study of the ecotoxicity of finished cosmetic products containing these filters is important. Objectives: We sought to assess ex vivo the toxicity of fivedoi:10.4236/jcdsa.2019.93020 fatcat:wql5qybsv5endbj4k5fuefptd4
more »... lsions containing UV-filters on coral cuttings of Seriatopora hystrix. Materials and Methods: Coral cuttings were put in contact with 5 different emulsions containing UV-filters. The toxicity readout was the ability to induce polyp retraction and/or fragment bleaching of the coral cuttings of Seriatopora hystrix. Results: In our experimental conditions, none of the five tested formulas neither induced any significant polyp retraction nor triggered fragment bleaching of the coral. Conclusions: The five tested emulsions containing UV-filters did not modify coral cuttings. In vivo, larger tests are necessary to verify the results of this ex vivo pilot study.
W e consider the problem of determining a set of optimal tariffs for an agent in the network, who owns a subset of all the arcs, and who receives revenue by setting the tariffs on the arcs he owns. Multiple rational clients are active in the network, who route their demands on the least expensive paths from source to destination. The cost of a path is determined by fixed costs and tariffs on the arcs of the path. We introduce a remodeling of the network, using shortest paths. We develop threedoi:10.1287/ijoc.1060.0177 fatcat:f47aoikjgrckdb4tmfwooouc7a
more »... gorithms based on this shortest-path graph model: a combinatorial branch-and-bound algorithm, a path-oriented mixed integer program, and a known-arc-oriented mixed integer program. Combined with reduction methods, this remodeling enables us to solve the problem to optimality, for quite large instances. We provide computational results for the methods developed and compare them with the results of the arc-oriented mixed integer programming formulation of the problem, applied to the original network.
This neuroimaging (functional magnetic resonance imaging) study investigated neural correlates of strategy selection. Young adults performed an arithmetic task in two different conditions. In both conditions, participants had to provide estimates of twodigit multiplication problems like 54 × 78. In the choice condition, participants had to select the better of two available rounding strategies, rounding-up (RU) strategy (i.e., doing 60 × 80 = 4,800) or rounding-down (RD) strategy (i.e., doingdoi:10.3389/fpsyg.2015.00061 pmid:25698995 pmcid:PMC4316698 fatcat:ybt75je4yngnbgscizyeoycr44
more »... × 70 = 3,500 to estimate product of 54 × 78). In the no-choice condition, participants did not have to select strategy on each problem but were told which strategy to use; they executed RU and RD strategies each on a series of problems. Participants also had a control task (i.e., providing correct products of multiplication problems like 40 × 50). Brain activations and performance were analyzed as a function of these conditions. Participants were able to frequently choose the better strategy in the choice condition; they were also slower when they executed the difficult RU than the easier RD. Neuroimaging data showed greater brain activations in right anterior cingulate cortex (ACC), dorso-lateral prefrontal cortex (DLPFC), and angular gyrus (ANG), when selecting (relative to executing) the better strategy on each problem. Moreover, RU was associated with more parietal cortex activation than RD.These results suggest an important role of fronto-parietal network in strategy selection and have important implications for our further understanding and modeling cognitive processes underlying strategy selection.
Lecture Notes in Computer Science
As structural and surface-based analyses gain interest for activation detection, morphometry and intersubject matching purposes, this paper proposes a method to perform structural group analyses directly on the cortical surface. Scale-space blobs are extracted from surface-based functional maps and matched across subjects. The process aims at identifying activations within a population despite the various effects due to variability. Results of the method are presented with simulated activations and with data from a somatotopy protocol.doi:10.1007/978-3-540-85988-8_114 fatcat:4en7c4laabcehpox53hb4nnxaq
« Previous Showing results 1 — 15 out of 3,252 results