If a person has Alzheimer’s disease, it can show up in many ways.
One of the most obvious signs is that their ability to remember and think becomes impaired. Mood, behavior and even movement can be affected by the condition.
But why does this happen?
From what we can see, it is because of physical changes in the brain that affect how it works.
The brain contains billions and billions of tiny cells. There are different types of cells with different jobs to do, but one of the best-known types of brain cell is the neuron.
Neurons pass signals between each other. This is the basis of how our brains receive and process information. This information exchange allows us to carry out activities such as thinking, remembering and moving.
In Alzheimer’s disease, some protein substances start to build up in the brain in a manner that affects how neurons work.
One type of protein fragment, called beta-amyloid, accumulates in between the neurons, forming clumps or plaques.
A different protein, called tau (rhymes with “wow”), which is normally involved in maintaining the internal structure of cells, forms “tangles” inside neurons.
Plaques and tangles tend to start in areas of the brain involved in memory and thinking and become more widespread as Alzheimer’s disease progresses.
Other changes can take place, too. For example, blood flow in the brain may alter and the brain may show signs of inflammation.
Such changes in the brain are linked with neurons (those “information connector” cells) dying and parts of the brain shrinking.
One of the sections of the brain affected in this way in Alzheimer’s disease is called the hippocampus. The hippocampus plays a strong role in memory. As the disease progresses, the brain can shrink quite dramatically.
You can find out more about how Alzheimer’s disease affects the brain here.