Poster A72, Saturday, March 24, 1:30–3:30 pm, Exhibit Hall C
Generalization in an object category learning paradigm is better in the morning than the evening
Anna Schapiro1, Mollie Bayda1, Eileen Cho1, Roy Cox1, Robert Stickgold1; 1Harvard Medical School / Beth Israel Deaconess Medical Center
Prior work has demonstrated that features of objects that are shared with other members of a category are better remembered after a night of sleep. We set out to test whether sleep would also benefit generalization to novel object category exemplars. Participants learned visual and verbal features of three categories (A, B, and C) of “satellite” objects. At the end of this training, we exposed them to two additional satellites, each composed of a combination of features from categories A and B. These satellites provided a bridge between the two categories, supporting the potential generalization that other combinations of features from A and B could also produce plausible satellite objects. In Experiment 1, we tested participants before and after a night of sleep, or before and after a day awake. There was no benefit of sleep, but instead a strong effect of time of day, where participants generalized better in the morning. In Experiment 2, we manipulated bridge item exposure to match initial generalization behavior across groups (despite testing at different times of day) and potentially reveal a sleep effect, but there was again no effect of sleep. In Experiment 3, tests were separated by a 24-hour delay, and we replicated the finding that generalization is much better in the morning and that sleep confers no benefit. These results suggest that for this paradigm, memory processing during sleep does not benefit generalization, and instead there is a strong benefit to testing in the morning.
Topic Area: LONG-TERM MEMORY: Semantic