Urs Maurer|Silvia Brem|Kerstin Bücher|Daniel Brandeis
Emerging Neurophysiological Specialization for Letter Strings
University of Zurich|University of Zurich|University of Zurich|University of Zurich
adult readers printed words letter strings activate specialized visual functions within 200 msec evident neurophysiological recordings brain activity fast specialized responses letter strings thought develop plastic changes visual system however unknown whether specialization emerges onset word reading represents precursor literacy compared 6yearold kindergarten children could yet read words adult readers age groups detected immediate repetitions visually presented words pseudowords symbol strings pictures eventrelated potential erp mapping maps seven corresponding erp segments children adults analyzed regarding fast 250 msec slow 300 msec specialization letter strings adults reliably differentiated words increased fast 150 msec occipitotemporal n1 activity symbols children showed later midoccipital n1 marginal wordsymbol differences absent children low letter knowledge children high letter knowledge showed fast sensitivity letter strings confined right occipitotemporal sites unlike stronger adult n1 specialization suggests critical degree early literacy induces immature fast specialization letter strings word reading becomes possible children also differentiated words symbols later segments increased right occipitotemporal negativity words slow specialization letter strings modulated letter knowledge absent adults possibly reflecting visual precursor literacy due visual familiarity letter strings