Effects of phonological neighbourhood density and frequency in picture naming
This research investigated the effect of several phonological neighbourhood measures on spoken word production. More specifically, it investigated the hypothesis, derived from predictions of the Neighbourhood Activation Model (Luce & Pisoni, 1998) in auditory word recognition, that effects of phonological neighbours would be stronger on targets of lower frequency compared to targets of higher frequency, and that effects of phonological neighbours of higher frequency than the target would have stronger effects than phonological neighbours overall. This possibility was first investigated in a simple picture naming study involving 40 Australian speakers (Australian data file). An significant interaction was found between target log frequency and summed higher frequency PNF (the summed frequency of phonological neighbours of higher frequency than the target) on picture naming response times. Next, these analyses were replicated in another publicly available dataset (UK Johnston data file) and the critical interaction was replicated (in addition to an interaction between target log frequency and higher frequency PND (the number of neighbours of higher frequency than the target). In a third experiment, simulations were run with a modified version of the DRC model of reading (Coltheart et al.) created to simulate spoken word production from semantics, to find a set of parameters capable of simulating the effect that was found in both of the behavioural experiments. The Excel file explains column names for the 3 datasets.