Spontaneous hippocampal hypersynchronicity and spike trains in EEG of adult APP23 mice. (A) Representative images of immunofluorescence stainings on hippocampal sections from non-transgenic (non-tg) and APP23 mice (4 months) for APP/Aβ (6E10). DAPI, 4',6-diamidino-2-phenylindole. Scale bars, 100 μm (B) APP23 transgenic hippocampal EEG during active phase of day-night cycle. EEG trace (local field potential, LFP) (upper panel) and activity trace (lower panel) showing spontaneous spike activity and spike train (marked up with dashed line). Representative recording from 5 animals is shown. (C) Magnification of EEG trace in B showing representative spike train in hippocampal recording from APP23 transgenic mouse. (D) Spike train quantifications for APP23 and non-transgenic (non-tg) recordings over 24 hours. (n = 5) Values are mean ± s.e.m.; ND, none detected (E) Hippocampal EEG from non-transgenic mouse during active phase of day-night cycle. EEG trace and magnification of EEG trace (marked up with dashed line) are shown. Representative recording from 5 animals is shown.