title: Fast dynamics of cortical functional and effective connectivity during word reading.
abstract: We describe for the first time the fast dynamics of functional and effective (causal) connectivity during word reading. Independent component analysis of high-density EEG recorded during a word reading task recovered multiple sources of electrical brain activity previously identified by fMRI and PET. Results confirmed the ventral occipito-temporal cortex (vOT) as a central hub for word reading, showing a progression of theta-band (3-7 Hz) and gamma-band (30-50 Hz) phase synchronization and directed theta-band and gamma-band information flow with both early visual areas and high-level language-processing areas. These results highlight the interplay between local and long-distance neural dynamics involved at each stage of the reading process. Moreover, these measures of functional and causal connectivity dynamics may be used as a benchmark for comparison with clinical populations (e.g. individuals with developmental dyslexia), such that disturbances in connectivity dynamics may provide insight as to underlying neurological problems with language processing, and their potential remediation.
authors.affiliation: Department of Psychology, University of British Columbia, Vancouver, British Columbia, Canada.
authors.forename: Nicolas
authors.initials: N
authors.lastname: Bedo
authors.affiliation: Behavioral and Cognitive Neuroscience Institute, Simon Fraser University, Burnaby, British Columbia, Canada ; Department of Psychology, Simon Fraser University, Burnaby, British Columbia, Canada.
authors.forename: Urs
authors.initials: U
authors.lastname: Ribary
authors.affiliation: Department of Psychology, University of British Columbia, Vancouver, British Columbia, Canada ; Brain Research Centre, University of British Columbia, Vancouver, British Columbia, Canada.
authors.forename: Lawrence M
authors.initials: LM
authors.lastname: Ward
mesh_terms: D000293:Adolescent; D000328:Adult; D001519:Behavior; D002540:Cerebral Cortex / Q000502:physiology*; D004569:Electroencephalography; D019277:Entropy; D005071:Evoked Potentials / Q000502:physiology; D005260:Female; D006801:Humans; D008297:Male; D009415:Nerve Net / Q000502:physiology*; D010775:Photic Stimulation; D011932:Reading; D013997:Time Factors; D014825:Vocabulary; D055815:Young Adult