Animal model of Alzheimer’s disease: characteristics of EEG and memory

Abstract

Abstract We studied the effects of aggregated amyloid β-peptide Aβ25–35 on spatial memory and the spectral-correlational characteristics of EEG of both the dorsal hippocampus and the frontal cortex both in adult and aged rats at the early stage of Aβ25–35 action. Spatial memory was characterized using a novel cognitive test. A decrease in low-frequency theta band oscillations in the dorsal hippocampus and the frontal cortex was observed. The mean coefficient of EEG cross-correlation between these structures was significantly reduced at the early stage of Aβ25–35 action both in adult and aged rats. In addition, we found that one month after Aβ25–35 injection spatial memory was impaired. These results suggest that the decrease in low-frequency theta band oscillations and the weakening of binding between the dorsal hippocampus and the frontal cortex under the action of Aβ25–35 may be an underlying cause of the typical memory breakdown associated with the Alzheimer’s disease.