20-month-olds can use negative evidence while learning word meanings

Decades of research in psychology have built models and theoretical assumptions about language development evaluating how children extract information from positive evidence to learn the meanings of novel words. In the present set of studies, we evaluated whether children can also consider negative evidence, information about what a word cannot refer to. Across two experiments (n = 73), we show that English-learning 20-month-olds can use negative evidence in the form of negative sentences (e.g., "This is not a danu") to constrain their interpretation of a novel word meaning ("danu"). These findings raise the possibility that learning word meanings through positive evidence alone, while possible, may not be the most accurate characterization of the word learning process and invite further developments of current word learning theories and models that incorporate negative evidence.