Neurons are the cells responsible for communicating important information to different areas of the brain. They use various chemical messengers, called neurotransmitters, to pass information to one another. The most abundant neurotransmitter in the brain is glutamate, a chemical on-switch that allows neurons to generate activity in other neurons. The brain needs glutamate for many different functions, including learning and memory. Still, too much of a good thing can become harmful— as is the case with this neurotransmitter. In Alzheimer’s disease (AD), the brain accumulates too much glutamate