It’s well known that Alzheimer’s affects more than five million people nationwide. Less has been known about how the disease actually begins to undermine brain functioning. Until now.

British scientists have discovered the functions of the area of the brain in which Alzheimer’s begins. They did this by focusing on one of the first brain areas to show changes in Alzheimer’s — the lateral entorhinal cortex.

The LEC is made up of layers of cells that form networks of connections with other brain regions. It also contains sub-systems that have different memory functions.

The team discovered that when a particular connection between one of the layers of the LEC and the hippocampus malfunctions, episodic memory is affected, but simpler forms of memory remain unaffected.

“This research is important as it gives us a very specific target when developing treatments and strategies to prevent neurodegeneration in Alzheimer’s disease,” said James Ainge, M.D., of the School of Psychology and Neuroscience at the University of St Andrews.Full findings appear in Current Biology.