The sand maze: An appetitive alternative to the Morris water maze.

摘要

The present paper introduced a new spatial task, called the sand maze that may be an alternative to the Morris water maze and other spatial tasks. The sand maze is an appetitive spatial task, which takes advantage of the natural foraging behaviors of rats by requiring them to locate buried Froot Loops cereal (FL) in a pool of sand. Experiment 1 examined spatial characteristics of the sand maze by rotating the maze 180° on the last day of training. The results showed that rats dug in locations that corresponded with the correct extramaze cues and not intramaze cues (like the buried FL). Experiment 2A examined the trial spacing effect during acquisition (massed or spaced training), retention (1 or 7 day retention periods), and extinction (spaced extinction). Massed training produced poorer performance during acquisition. However, this deficit was likely due to a performance deficit, rather than a learning deficit, because massed and spaced training produced equivalent levels of retention. In addition, massed training led to persistence during extinction, while spaced training did not. Experiment 2B compared the effects of partial and continuous reinforcement on acquisition, retention, and extinction following massed training. Partial reinforcement produced a deficit in responding during acquisition when compared to continuous reinforcement, however, no differences were observed between the two groups during retention or extinction testing. All rats had above chance retention for the correct location and showed spontaneous recovery of responding on Extinction Day 2. Experiment 3 examined spontaneous alternation behavior by using a spatial version and a non-spatial version of the sand maze. The sand maze was made into a non-spatial task by adding a salient intramaze cue to the maze that indicated the correct food locations. This experiment showed higher rates of alternation for the non-spatial version than the spatial version of the sand maze.