We are still not sure if other animals suffer from dementia. However, for the very first time, scientists have found the plaques and tangles that are characteristic of Alzheimer’s disease in the brains of chimpanzees. Whether or not finding the physical signs of Alzheimer’s means chimpanzees are experiencing the same cognitive symptoms is still up for debate.
The brains of people who have Alzheimer’s all contain plaques and tangles known as beta-amyloid proteins. These proteins build up in the brain slowly, causing cognitive issues such as memory loss, confusion, and changes in mood and temperament. Alzheimer’s disease is the sixth leading cause of death in the United States. There is currently no cure.
A team of researchers at Northeast Ohio Medical University studied the brains of 20 older chimpanzees, ages 37 to 62. They looked at four different brain regions that are most commonly affected by Alzheimer’s disease and found beta-amyloid proteins in 12 of the chimps’ brains. The older the chimp, the more plaques and tangles they saw, which is consistent with what Alzheimer’s does in people’s brains as well.
More data needs to be analyzed before scientists find out whether or not these plaques and tangles affect the chimps in the same way that they affect humans. So far, they have not seen any dementia-like symptoms in any of the chimps.