ON FUNCTIONAL BRAIN ASYMMETRIES IN PERCEPTUAL PRIMING

Brain asymmetries in implicit memory were studied using a perceptual i dentification priming paradigm. At the study phase, Subjects rated eit her the readability or the likeability of words. At the test phase, pe rceptual priming for these words was measured by presenting stimuli br iefly either in the left or in the right visual hemifield. The typefac e of the words was varied between the study and test. The orientation task manipulation at the study phase did not influence priming, althou gh it had a powerful effect on a test of explicit memory. Priming effe cts were form-specific: words which were studied in the same typeface as they were tested were primed more strongly than words which were st udied in a different typeface. No hemispheric asymmetries were observe d in form-specific priming, but in general, priming was greater in the right hemifield/left hemisphere. These findings suggest that the hemi spheres are equally effective in analysing and storing form-specific i nformation at the early stages of word recognition process. Asymmetrie s favoring the left hemisphere may develop at a higher, more abstract level of presemantic visual word form processing. (C) 1995 Academic Pr ess, Inc.