Why Alzheimer's patients can't recognize loved ones
Anyone with a loved one suffering fromAlzheimer's will tell you that one of the most heartbreaking aspectsof the disease is the patient's inability to recognize who you are.Now, new research is shedding light on exactly why this is,furthering our understanding of how the disease impairs perception.
There are currently more than fivemillion people living with Alzheimer's disease in the United States,and while there's no cure in sight, our understanding of thecondition is improving at an encouraging rate. Whether it's theknowledge that mimicking movements can help rehabilitate patients, orfindings out that causes are more diverse than previously thought,we're learning more about the disease as time goes on.
For the new study, which was conductedby researchers at the University of Montreal, the focus was ondetermining exactly why patients have difficultyrecognizing faces. It focused on how we're thought to perceive facesin the first place – known as holistic perception – wherein we don'tlook for individual features, but take in the whole picture instead.
The researchers worked with a group ofAlzheimer's patients, alongside a control group of healthy subjects.The two groups were shown photographs of faces and cars, both uprightand upside down. For the upside down images, the results between thetwo groups were similar.
However, for the upright selection ofimages, the rate at which the images were identified varieddramatically. The Alzheimer's patients were much slower than thehealthy subjects with the facial pictures, and made considerably moremistakes. On the other hand, they didn't have the same problems withthe upright cars, the recognition of which is not believed to requireholistic processing.
Those results can be seen as aconfirmation that our innate holistic processing abilities –specifically those related to faces – are impaired by the disease.
While the study doesn't lead directlyto new treatments, it does improve our understanding of the disease.It's essentially another piece of the puzzle, and one that could, theresearchers believe, help in the development of different strategiesfor helping patients to recognize their loved ones, such as gettingthem to focus more on individual facial features.
The research was published online inthe Journal of Alzheimer's Disease.
Source: University of Montreal