Sleep benefits cross-dimensional binding of spatial context in episodic memory

The active systems consolidation hypothesis predicts that sleep compared to wakefulness benefits context binding in episodic memory for retention intervals of up to 12 h. Extending previous research on sleep benefits in item-context associative memory, we investigated whether sleep also improves bound source memory for cross-dimensional context associations. In a source-monitoring experiment, we used intentionally learned pictures as items and incidentally learned horizontal and vertical screen positions as context dimensions to compare cross-dimensional binding in spatial source memory for retention intervals filled with natural night sleep versus daytime wakefulness. In line with the active systems consolidation hypothesis, multinomial modelling analyses revealed a significant sleep benefit in bound source memory for horizontal and vertical spatial locations of items. Hence, not only memory for item-context associations but also memory for cross-dimensional context associations benefits from sleep.