BLA stimulation effects on DG LTP.A, In the BLA Priming group (n = 8), a stimulation to the BLA (10 trains of 5 pulses at 100 Hz) was applied 30 sec before HFS to the PP. In the1 hr-BLA group (n = 7), a stimulation to the BLA (10 trains of 5 pulses at 100 Hz) was applied 1 hr before HFS to the PP. Priming stimulation of the BLA significantly increased LTP compared with the HFS and the 1 hr-BLA groups at all times tested (*significant difference between the BLA priming group and the two other groups; #Significant difference between the HFS and the 1 hr-BLA groups). A comparison between the groups before HFS to the PP did not reveal a significant difference in the levels of the EPSP, indicating a similar baseline. B, The spaced activation of the BLA had no effect on baseline EPSP levels either at 1 min or at 1 hr after BLA stimulation (before HFS to the PP).