Sex differences in lexical size across semantic categories

Recent studies have reported that males show better naming of nonliving things than females, while females show better naming of living things than males. Such effects may reflect sex differences in the size of lexicons across categories or their access/retrieval strategies. These possibilities were examined in three experiments using semantic fluency tasks for two living (animals, fruits) and two nonliving (tools, vehicles) categories. Experiment 1 documented better fluency for ‘fruits’ in females (n=300) and for ‘tools’ and ‘vehicles’ in males (n=300). Experiment 2 examined fluency consistency by re-testing a subgroup of subjects again 30 min later. This confirmed the pattern across sex and revealed that subjects reproduced 70% of the same words (even when not instructed to do so). Finally, in Experiment 3, a new sample of male and female subjects was tested for 4 min to exhaust their fluency lexicons and overcome access/strategy effects. This confirmed the female advantage for fruits and male advantage for tools. These findings are consistent with differences in the size of lexicons for males and females and are attributed to sex differences in domain-specific processing systems.