Protzner, AndreaSeyffarth, Sabine Martina2014-09-232014-11-172014-09-232014Seyffarth, S. M. (2014). For the Win: Brain Signal Variability as a Measure of Expertise in Competitive Scrabble® Players (Master's thesis, University of Calgary, Calgary, Canada). Retrieved from https://prism.ucalgary.ca. doi:10.11575/PRISM/26216http://hdl.handle.net/11023/1778I used multi-scale entropy (MSE) to quantify brain signal variability in order to examine differences mediated through expertise in visual word recognition (VWR). While, VWR is highly efficient in adult readers, competitive Scrabble players achieve superior performance through extended training. Participants (19 Scrabble experts and 19 controls) performed a lexical decision task (“Is it a word?”) during electroencephalography recording. Behavioural results suggest that Scrabble experts de-emphasize semantic information for lexical decisions, and are faster than controls at processing vertical words. Signal variability results suggest that the variability pattern underlying better Scrabble skill differs between Scrabble experts and controls. Although MSE decreased with higher skill in both groups, the topography of this effect was widespread in the Scrabble group, and sparser in controls. I interpret these findings as the recruitment of extended neural resources driven by long-term practice and a shift in VWR mechanisms with increasing Scrabble skill.engUniversity of Calgary graduate students retain copyright ownership and moral rights for their thesis. You may use this material in any way that is permitted by the Copyright Act or through licensing that has been assigned to the document. For uses that are not allowable under copyright legislation or licensing, you are required to seek permission.Psychology--CognitivePsychology--ExperimentalMSEScrabbleVariabilityEEGElectroencephalographylexical decision taskanagrammingexpertisevisual word recognitiondeliberate practicemulti scale entropyLDTmaster thesis10.11575/PRISM/26216