Neurons receive signals that either stimulate them to send signals to other neurons, or inhibit them from doing so. In normal brains, the balance between the stimulating and inhibiting inputs is tightly controlled. However, in many brains of people with cognitive impairment this balance appears to be disrupted, resulting in either excessive stimulating or excessive inhibiting or both of neurons. The proposed project aims to further investigate whether such imbalance may account for the cognitive decline in Alzheimer's disease, and whether pentylenetetrazole can be used to correct the imbalance. The proposed project further aims to explore several new methods for monitoring cognitive function in Alzheimer's disease and for exploring the effectiveness of pentylenetetrazole.