Eliminating visual clutter helps people with mild cognitive impairment

by Jason Maderer
In the high-interference trials, many photos of the same thing (a blob-like object) were shown. The photos varied only slightly when they weren’t a perfect match, either by shape, color or fill pattern. As expected, MCI patients struggled greatly to identify identical pairings. Credit: University of Toronto/Georgia Tech

(Medical Xpress)—A new study from Georgia Tech and the University of Toronto suggests that memory impairments for people diagnosed with early stage Alzheimer's disease may be due, in part, to problems in determining the differences between similar objects. The findings also support growing research indicating that a part of the brain once believed to support memory exclusively – the medial temporal lobe - also plays a role in object perception. The results are published in the October edition of Hippocampus.

(MCI) is a disorder commonly thought to be a to Alzheimer's disease. The study's , partnering with the Emory Alzheimer's Disease Research Center, tested MCI patients on their ability to determine whether two rotated, side-by-side pictures were different or identical.

In the high-interference trials, many photos of the same thing (a blob-like object) were shown. The photos varied only slightly when they weren't a perfect match, either by shape, color or fill pattern. As expected, MCI patients struggled greatly to identify identical pairings.

In the low-interference trials, these blob-like objects were interspersed with trials in which non-matches were more extreme and varied widely. For example, a picture of a butterfly was shown next to a photo of a . Interspersing the very similar blob-like objects with photos of dissimilar objects greatly reduced the amount of interference.

"Minimizing the degree of perceptual improved patients' object perception by reducing the number of visually similar features," said project leader Rachel Newsome, a University of Toronto Ph.D. student and Georgia Tech graduate.

The findings suggest that, under certain circumstances, reducing "visual clutter" could help MCI patients with . For example, buttons on a telephone tend to be the same size and color. Only the numbers are different – a very slight visual difference for someone who struggles with object perception. One solution could be a phone with varying sized buttons and different colors.

In the low-interference trials, pictures of more extreme, widely varied objects were interspersed with blob-like objects (used in high-performance trials). For example, a picture of a plant was shown next to a photo of a radio. Interspersing the very similar blob-like objects with photos of dissimilar objects greatly reduced the amount of interference. Minimizing the degree of perceptual interference improved patients’ object perception by reducing the number of visually similar features. Credit: University of Toronto/Georgia Tech

People diagnosed with MCI weren't the only ones to struggle in the study. The researchers performed the same tests on candidates at-risk for MCI, people who had previously shown no signs of . They performed the same as those with MCI, suggesting that the perception test could be used as an early indicator of cognitive impairment.

"People often associate MCI and dementia solely with memory impairment," said Georgia Tech Psychology Assistant Professor Audrey Duarte, one of the study's authors. "Memory and perception appear to be intertwined in the same area of the human brain."

Duarte and her colleagues are among the growing number of researchers studying Alzheimer's who believe damage to a small area of the medial temporal lobes, the perirhinal cortex, affects object perception.

"Not only does memory seem to be very closely linked to perception, but it's also likely that one affects the other," said Toronto's Morgan Barense, the final member of the team. "Alzheimer's patients may have trouble recognizing a loved one's face, not only because they can't remember it, but also because they aren't able to correctly perceive its distinct combination of features to begin with."

More information: onlinelibrary.wiley.com/doi/10.1002/hipo.22071/full

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Tausch
not rated yet Oct 01, 2012
http://medicalxpr...ays.html

The authors to the link above disagree with:

The lack of features (or if you will - the less 'clutter')when perceiving your surroundings the less likely your memory of that event is prone or susceptible to lost.

The authors of this article here agree to the assertion:

The lack of features (or if you will - the less 'clutter')when perceiving your surroundings the less likely your memory of that event is prone or susceptible to lost.

In a 'clutter-less' (featureless poor)world Alzheimer patients have perfect memory - all humans do.

It only takes one outstanding (in this case , visual) feature to recognize a loved one's face - the brain and mind want more - to store all the perceptions delivered by more than one sense - in this case the visual.

Object perception runs parallel along all the senses.
Focus on just one feature of an object 'strengthens' memory retention - the less remembered, the less forgotten.

Mike_Massen
not rated yet Oct 01, 2012
It seems to me, after having looked after a parent with a variant of Alzheimers, that an initial symptom is adherence to an idea or ideal which cannot easily be argued against despite exploration of logic or rationale which encompasses any complexity or diversity.

ie Fixation and attachment to an idea which in essence is dynamic yet viewed as concrete static by the patient - this seems to be a key issue, I have since seen this several times as indication of some biological or psychological aspect of the initial offerings of alzheimers...

Thanks