Age-of-Acquisition (AoA) effects in word and object naming in Turkish, using Snodgrass and Vanderwart pictures.

Evidence to date suggests that AoA plays an important role in word naming across a range of alphabetic writing systems with a varying degree of transparency between print and sound. This is contrary to the predictions of the arbitrary mapping hypothesis (Ellis & Lambon-Ralph, 2000) which argue that AoA effects should be stronger for tasks that involve arbitrary mappings between representations than for tasks that involve consistent mappings. Independent ratings were obtained for AoA, frequency, name agreement and object familiarity from Turkish undergraduates for all items in the Snodgrass and Vanderwart (1980) line drawing set. The role of AoA was explored in atypically consistent Turkish in an object and a word naming experiment using the same subset of stimuli. The findings dispute the claim that AoA effects should be reduced for orthographies with consistent mappings between print and sound and are discussed with reference to the arbitrary mapping framework