Why people with Alzheimer's stop recognizing their loved ones

  • A finding that Alzheimer's sufferers' failure to recognize familiar faces is rooted in an impairment in holistic perception rather than memory loss, suggests new strategies to help patients recognize their loved ones for longer.

People with Alzheimer's disease develop problems in recognizing familiar faces. It has been thought that this is just part of their general impairment, but a new study indicates that a specific, face-related impairment develops early in the disease. This impairment has to do with the recognition of a face as a whole.

Face recognition has two aspects to it: holistic (seeing the face as a whole) and featural (processing individual features of the face). While both are useful in object recognition, expert recognition (and face recognition is usually something humans are expert in) is built on a shift from featural to holistic processing.

The study compared the ability of people with mild Alzheimer's and healthy age- and education-matched seniors to recognize faces and cars in photos that were either upright or upside down. It found that those with Alzheimer's performed comparably to the control group in processing the upside-down faces and cars. This type of processing requires an analysis of the various features. Those with Alzheimer’s also performed normally in recognizing upright cars (car experts are likely to use holistic processing, but those with less expertise will depend more on featural processing). However, they were much slower and less accurate in recognizing faces.

Realizing that impaired facial recognition is based on a holistic perception problem, rather than being simply another failure of memory, suggests that strategies such as focusing on particular facial features or on voice recognition may help patients recognize their loved ones for longer.

http://www.eurekalert.org/pub_releases/2016-04/uom-wdp040816.php

Reference: 

Related News

A study involving mice lacking a master clock gene called Bmal1 has found that as the mice aged, their brains showed patterns of damage similar to those seen in Alzheimer's disease and other neurodegenerative disorders. Many of the injuries seemed to be caused by free radicals.

A new study involving 96 older adults initially free of dementia at the time of enrollment, of whom 12 subsequently developed mild Alzheimer’s, has clarified three fundamental issues about Alzheimer's: where it starts, why it starts there, and how it spreads.

Analysis of 5715 cases from the National Alzheimer's Coordinating Center (NACC) database has found that nearly 80% of more than 4600 Alzheimer's disease patients showed some degree of vascular pathology, compared with 67% of the controls, and 66% in the Parkinson's group.

The jugular venous reflux (JVR) occurs when the pressure gradient reverses the direction of blood flow in the veins, causing blood to leak backwards into the brain.

The

Following on from the evidence that Alzheimer’s brains show higher levels of metals such as iron, copper, and zinc, a mouse study has found that amyloid plaques in Alzheimer’s-like brains with significant neurodegeneration have about 25% more copper than those with little neurodegeneration.

An Italian study has found that a significant percentage of Alzheimer’s patients suffer from Obstructive Sleep Apnea Syndrome. This respiratory disorder, which causes people to temporarily stop breathing during their sleep, affects cerebral blood flow, promoting cognitive decline.

Data from 70 older adults (average age 76) in the Baltimore Longitudinal Study of Aging has found that those who reported poorer sleep (shorter sleep duration and lower sleep quality) showed a greater buildup of amyloid-beta plaques.

A new discovery helps explain why the “Alzheimer’s gene” ApoE4 is such a risk factor.

Analyses of cerebrospinal fluid from 15 patients with Alzheimer's disease, 20 patients with mild cognitive impairment, and 21 control subjects, plus brain tissue from

Pages

Subscribe to Latest newsSubscribe to Latest newsSubscribe to Latest health news