Nameability supports rule-based category learning in children and adults

Abstract

The present study tested the hypothesis that verbal labels support category induction by providing compact hypotheses. Ninety-seven 4- to 6-year-old children (M = 63.2 months; 46 female, 51 male; 77% White, 8% more than one race, 4% Asian, and 3% Black; tested 2018) and 90 adults (M = 20.1 years; 70 female, 20 male) in the Midwestern United States learned novel categories with features that were easy (e.g., "red") or difficult (e.g., "mauve") to name. Adults (d = 1.06) and-to a lesser extent-children (d = 0.57; final training block) learned categories composed of more nameable features better. Children's knowledge of difficult-to-name color words predicted their learning for categories with difficult-to-name features. Rule-based category learning may be supported by the emerging ability to form verbal hypotheses.

Figure 1.

(A) Experimental stimuli and category structure in the training phase. (B) Task design. Participants were asked which alien would like to eat the “snack” (color wheel) and were provided feedback after their selection. The progress bar depicts the number of “snacks” (trials) remaining.

Figure 2.

Adults’ performance on the category learning task in the High Nameability condition (solid line) and Low Nameability condition (dashed line) during the two rounds of training. Horizontal dashed line indicates chance-level responding. Error bars represent ±1 SE of the within-subject corrected mean (Morey, 2008).

Figure 3.

Children’s performance on the category learning task during the two rounds of training. Dashed line indicates chance level responding. Error bars represent ±1 SE of the within-subject corrected mean (Morey, 2008).

Figure 4.

Relation between low nameability color word knowledge and categorization accuracy for adults and children in the High vs. Low Nameability condition.