Figure 2: Effect of 5 pmoles amyloid beta on the sensory-induced hippocampal theta oscillations. (a) Representative field recordings obtained from the hippocampal fissure in a urethane-anaesthetized rat at rest (blue recording) and upon sensory stimulation (red recording). (b) and (c) show the spectrograms and the power spectra, respectively, of the traces shown in (a). The blue spectrum corresponds to the recording at rest, and the red power spectrum corresponds to the recording upon sensory stimulation. The inset in (c) shows the quantification of change in power upon sensory stimulation, compared with basal hippocampal activity. *Indicates a significant difference compared to control (; Wilcoxon signed-rank test).