ILABS Brain Seminar
October 29 - Jason Yeatman Hierarchical coding of letter strings in the ventral stream: dissecting the inner organization of the visual word-form system. Vinckier F1, Dehaene S, Jobert A, Dubus JP, Sigman M, Cohen L. Neuron. 2007 Jul 5;55(1):143-56.
Abstract Visual word recognition has been proposed to rely on a hierarchy of increasingly complex neuronal detectors, from individual letters to bigrams and morphemes. We used fMRI to test whether such a hierarchy is present in the left occipitotemporal cortex, at the site of the visual word-form area, and with an anterior-to-posterior progression. We exposed adult readers to (1) false-font strings; (2) strings of infrequent letters; (3) strings of frequent letters but rare bigrams; (4) strings with frequent bigrams but rare quadrigrams; (5) strings with frequent quadrigrams; (6) real words. A gradient of selectivity was observed through the entire span of the occipitotemporal cortex, with activation becoming more selective for higher-level stimuli toward the anterior fusiform region. A similar gradient was also seen in left inferior frontoinsular cortex. Those gradients were asymmetrical in favor of the left hemisphere. We conclude that the left occipitotemporal visual word-form area, far from being a homogeneous structure, presents a high degree of functional and spatial hierarchical organization which must result from a tuning process during reading acquisition.
A good related paper for background: Binder, Jeffrey R., et al. "Tuning of the human left fusiform gyrus to sublexical orthographic structure." Neuroimage 33.2 (2006): 739-748.
November 5 - No Brain Seminar
November 12 - Ross Maddox Tanner, Darren, Kara Morgan‐Short, and Steven J. Luck. "How inappropriate high‐pass filters can produce artifactual effects and incorrect conclusions in ERP studies of language and cognition." Psychophysiology (2015). http://www.ncbi.nlm.nih.gov/pubmed/25903295 This will be an informal discussion of these issues so please read the paper and plan to participate
November 19 - Ariel Rokem & Jason Yeatman Data sharing. Scientific transparency and reproducibility has become a major worry among scientists across disciplines and has also seen a lot of recent media attention. In response to these concerns, funding agencies and journals have been revising their policies on making published data openly available. We will lead a discussion on (1) best practices in data sharing, (2) resources that support and facilitate data sharing, (3) what data sharing means for the careers of young scientists.
November 26 - Thanksgiving
December 3 - Mark Wronkiewicz Something cool with decoding and single trial MEG analysis
December 10 - Alex White Divided attention and reading.
December 17 - Patrick Donnelly RAVE-O Reading Intervention Program.
