The effect of orthography on the visual processing of affixed words: Evidence from Bengali

The view that morphologically complex words are decomposed into constituent morphemes during lexical access has gained traction in the psycholinguistic literature, which in turn has had significant implications for theories of lexical organisation and processing. Nevertheless, the bulk of evidence for how morphologically complex Indo-European words are accessed and stored is based on based on Latinate scripts, where the orthography tends to be sequential. In many languages however, it is not straightforward to determine the internal structure of the word from the script alone. To critically examine the morphological decomposition in the visual domain, we present results from a visual delayed priming study covering every possible combination of morphologically complex words (i.e. stem ∼ prefixed, stem ∼ suffixed, prefixed - prefixed, suffixed - suffixed, and prefixed ∼ suffixed) in Bengali, a language rich with derivational morphology and orthographic complexity. Results for configurations containing stems (stem ∼ affixed) showed the only priming effects in the study; crucially, these findings depended heavily on whether the prime was a stem or affixed word. When the prime was a stem word, responses to both prefixed and suffixed targets were facilitated to a similar degree. When the primes consisted of affixed words (either prefixed or suffixed), they did not reliably prime stem targets. We also tested relationships between all affixed words and found no reliable priming effect for any combination. We argue that our results reflect not only modality-specific aspects of processing, but also asymmetries in the orthographic significance of phonological processes occurring at the stem-affix boundaries in Bengali.