1 Research article 2 An optimal dichotic-listening paradigm for the assessment of hemispheric 3 dominance for speech processing 4 5 René Westerhausen (1,2)* & Fredrik Samuelsen (2) 6 7 (1) Department of Psychology, University of Oslo, Norway 8 (2) Department of Biological and Medical Psychology, University of Bergen, Norway 9 10 Running title: Optimal dichotic-listening paradigm 11 12 13 *Corresponding author 14 René Westerhausen 15 Department of Psychology, University of Oslo, 16 POB 1094 Blindern, 0317 Oslo, Norway 17 email:
[email protected], Phone: (+47) 228 45230 18 1 19 Abstract 20 Dichotic-listening paradigms are widely accepted as non-invasive tests of hemispheric 21 dominance for language processing and represent a standard diagnostic tool for the 22 assessment of developmental auditory and language disorders. Despite its popularity in 23 research and clinical settings, dichotic paradigms show comparatively low reliability, 24 significantly threatening the validity of conclusions drawn from the results. Thus, the aim of 25 the present work was to design and evaluate a novel, highly reliable dichotic-listening 26 paradigm for the assessment of hemispheric differences. Based on an extensive literature 27 review, the paradigm was optimized to account for the main experimental variables which are 28 known to systematically bias task performance or affect random error variance. The main 29 design principle was to minimize the relevance of higher cognitive functions on task 30 performance in order to obtain stimulus-driven laterality estimates. To this end, the key 31 design features of the paradigm were the use of stop-consonant vowel (CV) syllables as 32 stimulus material, a single stimulus pair per trial presentation mode, and a free recall (single) 33 response instruction.