Age of Acquisition and Word Frequency Effects in Picture Naming: A Dual-Task Investigation

In 2 experiments, the authors explored age of acquisition (AoA) and word frequency (WF) effects in

picture naming using the psychological refractory period paradigm. In Experiment 1, participants named

a picture and then, a short time later, categorized 1 of 3 possible auditory tones as high, medium, or low.

Both AoA (Experiment 1A) and WF (Experiment 1B) effects propagated onto tone discrimination

reaction times (RTs), with the effects of AoA being stronger. In Experiment 2, the to-be-named picture

followed the auditory tone by a varying interval. As the interval decreased, picture naming RTs increased.

The relationship between the interval and AoA (Experiment 2A) was reliably underadditive; AoA effects

were eliminated at the shortest interval. In contrast, WF (Experiment 2B) was additive with the effects

of the interval. These results demonstrate an empirical dissociation between AoA and WF effects. AoA

affects processing stages that precede those that are sensitive to WF. The implications for theories of

picture naming are discussed.