Article

Visual word recognition: The first half second

Division of Psychology, School of Biology, University of Newcastle, UK.
NeuroImage (Impact Factor: 6.36). 09/2004; 22(4):1819-25. DOI: 10.1016/j.neuroimage.2004.05.004
Source: OAI

ABSTRACT We used magnetoencephalography (MEG) to map the spatiotemporal evolution of cortical activity for visual word recognition. We show that for five-letter words, activity in the left hemisphere (LH) fusiform gyrus expands systematically in both the posterior-anterior and medial-lateral directions over the course of the first 500 ms after stimulus presentation. Contrary to what would be expected from cognitive models and hemodynamic studies, the component of this activity that spatially coincides with the visual word form area (VWFA) is not active until around 200 ms post-stimulus, and critically, this activity is preceded by and co-active with activity in parts of the inferior frontal gyrus (IFG, BA44/6). The spread of activity in the VWFA for words does not appear in isolation but is co-active in parallel with spread of activity in anterior middle temporal gyrus (aMTG, BA 21 and 38), posterior middle temporal gyrus (pMTG, BA37/39), and IFG.

Download full-text

Full-text

Available from: Piers Cornelissen, Aug 17, 2015

Click to see the full-text of:

Article: Visual word recognition: The first half second

368.59 KB

See full-text
0 Followers
 · 
119 Views
  • Source
    • "For example , recall the evidence that Broca's area activity accompanies dorsal circuit activity early in reading development when children rely on decoding processes. In contrast, skilled readers who rarely use decoding exhibit activity in the ventral network that connect Broca's area and the VWFA (Price & Devlin, 2011; Woodhead et al., 2012; Pammer et al., 2004). In both the child studies and the adult studies, activity in Broca's area accompanied word recognition. "
    [Show abstract] [Hide abstract]
    ABSTRACT: This chapter addresses the observation that reading speed and reading intonation tend to develop together in typical readers, yet current theories of phonological processing do not ex-plain this developmental relationship. To explore the connection between prosody and fluency, I 0first discuss skilled reading processes and then turn to the development of reading fluency in children. Recent eye movement data from skilled readers indicates that automatically processing prosodic phonological information speeds word recognition during silent reading. After explicating the distinction between intentional decoding processes and automatic phonological precoding, I propose how precoding could shorten skilled word recognition time through a process termed prosodic constraint. A focused review of brain imaging studies discusses data consistent with prosodic constraint, and indicates the neural networks that could support it. Finally, I dis-cuss the roles that several phonological processes could play in developing reading fluency.
    The Fluent Brain, Edited by Edited by A. Khateb and I.B. Kochova, 08/2015; Springer-Verlag.
    • "The activation time course of the ROIs investigated here begins earlier than what has been observed with EEG or MEG techniques. Indeed, several studies reported a similar activation time course for vOT, pMTG, and SMG around 200 msec from stimulus onset (Pammer et al., 2004; Rossion, Joyce, Cottrell, & Tarr, 2003; Bentin, Mouchetant- Rostaing, Giard, Echallier, & Pernier, 1999; Tarkiainen et al., 1999). The timing difference between EEG/MEG and TMS studies could be explained by the fact that ERP components arise from large-scale neuronal synchrony across activity in multiple structures and, therefore, lag behind the earliest wave of activity that is affected by magnetic stimulation in any given structure (Walsh & Cowey, 2000; Schroeder, Mehta, & Givre, 1998). "
    [Show abstract] [Hide abstract]
    ABSTRACT: Cognitive theories on reading propose that the characteristics of written stimuli determine how they are processed in the brain. However, whether the brain distinguishes between regular words, irregular words, and pseudowords already at an early stage of the reading process is still subject to debate. Here we used chronometric TMS to address this issue. During the first 140 msec of regular word, irregular word, and pseudoword reading, TMS was used to disrupt the function of the ventral occipitotemporal, posterior middle temporal, and supramarginal gyri, which are key areas involved in orthographic, semantic, and phonological processing, respectively. Early TMS stimulation delivered on posterior middle temporal and supramarginal gyri affected regular and irregular word, but not pseudoword, reading. In contrast, ventral occipitotemporal disruption affected both word and pseudoword reading. We thus found evidence for an early distinction between word and pseudoword processing in the semantic and phonological systems, but not in the orthographic system.
    Journal of Cognitive Neuroscience 01/2015; 27(6):1-16. DOI:10.1162/jocn_a_00779 · 4.69 Impact Factor
  • Source
    • "Likewise, Twomey, Kawabata Duncan, Price, and Devlin (2011) found that the activation of the left ventral occipito-temporal cortex, a brain structure involved in early stage processing during visual word recognition, was modulated differently by emphasizing phonological versus orthographical criteria in the lexical decision task. Further evidence along the same lines was provided by Cornelissen et al. (2009), who used magnetoencephalography (MEG) measures to show very early coactivation (within 200 ms) of speech motor areas and fusiform gyrus (orthographic word-form processing ) during the presentation of words, consonant strings, and unfamiliar faces (see also Cai, Paulignan, Brysbaert, Ibarrola, & Nazir, 2010; Devlin, Jamison, Gonnerman, & Matthews, 2006; Kherif, Josse, & Price, 2011; Pammer et al., 2004). "
    [Show abstract] [Hide abstract]
    ABSTRACT: A number of experiments have revealed that matched-case identity PRIME-TARGET pairs are responded to faster than mismatched-case identity prime-TARGET pairs for pseudowords (e.g., JUDPE-JUDPE<judpe-JUDPE), but not for words (JUDGE-JUDGE=judge-JUDGE). These findings suggest that prime-target integration processes are enhanced when the stimuli tap onto lexical representations, overriding physical differences between the stimuli (e.g., case). To track the time course of this phenomenon, we conducted an ERP masked priming lexical decision experiment that manipulated matched vs. mismatched case identity in words and pseudowords. Behavioral results replicated previous research. The ERP waves revealed that matched-case identity-priming effects were found at very early time epochs (N/P150 effects) for words and pseudowords. Importantly, at around 200 ms after target onset (N250), these differences disappeared for words but not for pseudowords. These findings suggest that different-case word forms (lowercase and uppercase) tap onto the same abstract representation, leading to prime-target integration very early in processing. In contrast, different-case pseudoword forms are processed as two different representations. This word/pseudoword dissociation has important implications for neural accounts of visual-word recognition.
    Cognitive Affective & Behavioral Neuroscience 12/2014; 15(2). DOI:10.3758/s13415-014-0330-7 · 3.21 Impact Factor
Show more