Picture Naming and Lexical Access in italian children and adults

Normative data are described and compared for 34 Italian-speaking children (5-6 years of age) and 50 Italian-speaking adults in a timed picture-naming task, with 250 pictures (simple line drawings). Dependent measures include overall nameability, percent agreement on the most frequent name (target), number of alternative names provided, overall reaction time and latency to produce the target name. Independent measures (characteristics of target words and pictures that might affect naming) include frequency (from both adult and child norms), age of acquisition (an objective measure from early lexical development norms, and a subjective measure based on adult ratings), length (in syllables and characters), animacy, semantic category, various word structure and grammatical category measures specific to Italian, and an objective measure of picture complexity. Although children were substantially slower and less accurate than adults, child and adult performance was highly correlated, and similar correlations were obtained for children and adults between lexical predictors and naming times. However, word complexity had effects on adults that were not seen in children, and grammatical gender had effects on children that were not seen in adults. Adult ratings of age of acquisition had strong effects on both children and adults (and reduced or eliminated effects of frequency in regression analyses), but an objective measure of age of acquisition only affected children (and did not eliminate frequency effects in regression analyses). Differences were also observed in the semantic categories that were easiest for children vs. adults.