Figure 1.

LTP is enhanced following spatial enrichment for 8 wk. LTP induced by a single 1-sec burst of 100-Hz stimulation (1-sec duration) is less robust in slices from mice housed in standard cages (open triangles, n = 13 mice, 13 slices) than in slices from mice housed in spatially enriched cages (open circles, n = 10 mice, 13 slices). LTP in enriched slices was blocked by an antagonist of NMDA receptors, APV (100 μM; closed circles, n = 7 mice, nine slices). Sample fEPSP traces were recorded from slices 50 min after LTP induction.