Polysemy in the mental lexicon: relatedness and frequency affect representational overlap

Meaning relatedness affects storage of ambiguous words in the mental lexicon: unrelated meanings (homonymy) are stored separately whereas related senses (polysemy) are stored as one large representational entry. We hypothesised that word frequency could have similar effects on storage, with low-frequency words having high representational overlap and high-frequency words having low representational overlap. Participants performed lexical decision or semantic categorisation to high- and low-frequency nouns with few and many senses. Results showed a three-way interaction between frequency, task type, and polysemy. Low-frequency words showed a polysemy advantage with lexical decision but a polysemy disadvantage with semantic categorisation, whereas high-frequency words showed the opposite pattern. These results confirmed our hypothesis that relatedness and word frequency have similar effects on storage of ambiguous words.