The sum of your memories constitute who you are. Creating and storing memories is one of the brain's most remarkable functions, and takes place deep inside the brain, in the hippocampus. Along with the entorhinal cortex, the hippocampus collects input from the many parts of the brain that process what our five senses record, and links this information to our emotions (regulated by the amygdala) and the brain regions we use to think, plan, and move. This information arrives through the connections between neurons which create a living, dynamic framework for everything that we see, hear, taste, smell, touch and experience. The entorhinal cortex/ hippocampus region is one of the first areas to be affected by Alzheimer's disease. In Alzheimer's, beta amyloid, a protein that is made by brain cells during normal metabolism, is mishandled and abnormally accumulates to form large plaques between the nerve cells in this brain region and then more generally across the brain. While amyloid builds up, another normal protein inside nerve cells, tau, undergoes changes that produce a second tell-tale sign of Alzheimer's disease: neurofibrillary tangles. Disrupting the connections between nerve cells leads to the loss of essential brain function and the debilitating clinical symptoms of Alzheimer's.