Labeling and task-relevant information UNCORRECTED MS. IN PRESS in Language, Cognition and Neuroscience Recognizing a zebra from its stripes and the stripes from “zebra”: the role of verbal labels in selecting category relevant information

Distinguishing members from non-members of some categories can be accomplished by identifying one or several diagnostic features (e.g., zebra-stripes are diagnostic of zebras). Other categories lack diagnostic features (e.g., dogs). Consequently, distinguishing members from nonmembers requires attending to many correlated dimensions. Interestingly, children and nonhuman animals are less adept at using diagnostic features compared to adults—possibly due to adults’ more developed verbal labeling abilities. We examined whether recognition of categories with diagnostic features (“sparse” categories) is (1) linked to better abilities to selectively attend to relevant information and (2) aided by labeling. In Experiments 1-2, we quantify and validate a measure of category sparsity. Experiment 3 demonstrates that sparse categorization, assessed by an implicit naming task, correlates with performance in the flanker task, a measure of selective attention. Experiment 4 demonstrates up-regulating activity over Wernicke’s area via transcranial direct current stimulation—hypothesized to enhance labeling—selectively improves sparse categorization.