Table 1.

Subject assignment and experimental design.

	--Exp'al Condition--		----------------Experimental Phase---------------
Littermate	Sampling	Behavioral	Preexposure	Sac	Training	Sac	Testing
1	Preexp	Pre	Context A	x
2		Alt-Pre	Context B	x
3		Baseline	Home cage	x
4	Training	Pre	Context A		Context A	x
5		Alt-Pre	Context B		Context A	x
6		Baseline	Context A/B		Home cage	x
7	Behavior	Pre	Context A		Context A		Context A
8		Alt-Pre	Context B		Context A		Context A