Written age-of-acquisition effects reflect family resemblance in the lexical network

Abstract

The arbitrary mapping hypothesis assumes that age-of-acquisition (AoA) effects on oral reading depend on whether phonology can be predicted from orthography. One prediction that follows is that AoA effects will be larger for written words with inconsistent rime spellings than for written words with consistent rime spellings. An alternative hypothesis is that AoA effects on oral reading depend on the family resemblance between lexical items that share orthography-to-phonology mappings. The results from a multiple regression study show that the effects of written AoA on oral reading interact with the number of words containing the rime. Specifically, written AoA has a larger effect on the oral reading of consistent words with few family members than on that of inconsistent words with many family members. The conclusion from these results is that a binary distinction between predictable and unpredictable mappings is not sufficient to explain effects of written AoA on oral reading.