title: Framing effects reveal discrete lexical-semantic and sublexical procedures in reading: an fMRI study.
abstract: According to the dual-route model, a printed string of letters can be processed by either a grapheme-to-phoneme conversion (GPC) route or a lexical-semantic route. Although meta-analyses of the imaging literature support the existence of distinct but interacting reading procedures, individual neuroimaging studies that explored neural correlates of reading yielded inconclusive results. We used a list-manipulation paradigm to provide a fresh empirical look at this issue and to isolate specific areas that underlie the two reading procedures. In a lexical condition, we embedded disyllabic Italian words (target stimuli) in lists of either loanwords or trisyllabic Italian words with unpredictable stress position. In a GPC condition, similar target stimuli were included within lists of pseudowords. The procedure was designed to induce participants to emphasize either the lexical-semantic or the GPC reading procedure, while controlling for possible linguistic confounds and keeping the reading task requirements stable across the two conditions. Thirty-three adults participated in the behavioral study, and 20 further adult participants were included in the fMRI study. At the behavioral level, we found sizeable effects of the framing manipulations that included slower voice onset times for stimuli in the pseudoword frames. At the functional anatomical level, the occipital and temporal regions, and the intraparietal sulcus were specifically activated when subjects were reading target words in a lexical frame. The inferior parietal and anterior fusiform cortex were specifically activated in the GPC condition. These patterns of activation represented a valid classifying model of fMRI images associated with target reading in both frames in the multi-voxel pattern analyses. Further activations were shared by the two procedures in the occipital and inferior parietal areas, in the premotor cortex, in the frontal regions and the left supplementary motor area. These regions are most likely involved in either early input or late output processes.
authors.affiliation: Psychology Department, University of Milan-Bicocca Milan, Italy ; NeuroMI -Milan Center for Neuroscience Milan, Italy.
authors.forename: Laura
authors.initials: L
authors.lastname: Danelli
authors.affiliation: Psychology Department, University of Milan-Bicocca Milan, Italy ; Center for Mind/Brain Sciences, University of Trento Rovereto, Italy.
authors.forename: Marco
authors.initials: M
authors.lastname: Marelli
authors.affiliation: Psychology Department, University of Milan-Bicocca Milan, Italy ; NeuroMI -Milan Center for Neuroscience Milan, Italy.
authors.forename: Manuela
authors.initials: M
authors.lastname: Berlingeri
authors.affiliation: Division of Neuroscience and Department of Nuclear Medicine, San Raffaele Scientific Institute Milan, Italy.
authors.forename: Marco
authors.initials: M
authors.lastname: Tettamanti
authors.affiliation: Neuroradiology Department, Niguarda Ca' Granda Hospital Milan, Italy.
authors.forename: Maurizio
authors.initials: M
authors.lastname: Sberna
authors.affiliation: Psychology Department, University of Milan-Bicocca Milan, Italy ; NeuroMI -Milan Center for Neuroscience Milan, Italy ; fMRI Unit, IRCCS Galeazzi Milan, Italy.
authors.forename: Eraldo
authors.initials: E
authors.lastname: Paulesu
authors.affiliation: Psychology Department, University of Milan-Bicocca Milan, Italy ; NeuroMI -Milan Center for Neuroscience Milan, Italy.
authors.forename: Claudio
authors.initials: C
authors.lastname: Luzzatti
keywords: dual-route model; fMRI; lexical-semantic procedure; list-manipulation paradigm; multi-voxel pattern analysis (MVPA); reading; sublexical procedure