Discrimination of what, when, and where is not based on time of day

Abstract

Rats (n = 6) visited four baited locations (randomly chosen on each trial; study phase), one of which was randomly selected to provide chocolate. After short (1-h) or long (25-h) retention intervals (RIs), eight locations were available, and the four locations not available in the study phase provided food (test phase); the chocolate location also provided food after long RIs. More visits to the chocolate location occurred after long RIs than after short RIs. Next, chocolate was paired with LiCl during the long RI (i.e., after encoding the chocolate location). Fewer revisits to the chocolate location occurred after LiCl than in previous testing with the long RI. The rats demonstrated complete transfer when grape replaced chocolate after LiCl-chocolate pairing. The discrimination of what, when, and where could not be based on adopting different revisit strategies at different times of testing.