Differences in the Processing of Prefixes and Suffixes Revealed by a Letter-Search Task

A letter-search task was used to test the hypothesis that affixes are chunked during morphological processing and that such chunking might operate differently for prefixes and suffixes. Participants had to detect a letter target that was embedded either in a prefix or suffix (e.g., ‘R’ in propoint or filmure) or in a non-prefix beginning or non-suffix ending (e.g., ‘R’ in cropoint or filmire). Prefixed and suffixed letter-strings comprised real stems and affixes but never formed a real word. Effects of letter cluster frequency were also investigated by manipulating the frequency of non-affix beginnings and endings. Letter search took longer in suffixes compared with non-suffix endings but not for prefixes compared with non-prefix beginnings. Moreover, performance was not affected by letter cluster frequency. We interpret our findings in the light of recent accounts of morpho-orthographic segmentation and the different function of prefixes and suffixes.