The nerve cells, or neurons, in a healthy brain process information and transmit it along branches that connect in a complex network called a neuron forest. Your thought processes and memories travel through that neuron forest as electrical charges; chemical bursts called neurotransmitters carry information from cell to cell. Over the years, information and experiences create patterns in the brain that help us to retain memories, skills, knowledge and more.
AD can disrupt both the electrical charges and patterns and prevent neurons from functioning and interacting. Eventually, the nerve cells die, the brain shrinks, and the patient gradually loses the ability to think, learn, remember, plan and understand. Plaques, or clusters of protein, build up between neurons, and the cells contain tangles of another protein, both suspected to be instrumental in causing cell death, perhaps by preventing signals and nutrients from traveling from cell to cell.