Are age-of-acquisition effects on object naming due simply to differences in object recognition? Comments on levelt (2002).

Levelt (2002) argued that apparent effects of word frequency and age of acquisition (AoA) reported in recent picture naming studies might actually be confounded effects operating at the level of object recognition, rather than relevant to theories of lexical retrieval. In order to investigate this issue, AoA effects were examined in an object recognition memory task (Experiments 1 and 2) and a word-picture verification task (Experiment 3) and compared with those found in naming tasks using the same pictures. Contrary to Levelt's concerns, the results of the three experiments show that the AoA effect on picture naming has a lexical origin and does not simply result from a possible confound of object identification times.