Mild memory loss is not a part of normal aging

Sep 15, 2010

Simply getting older is not the cause of mild memory lapses often called senior moments, according to a new study by researchers at the Rush Alzheimer's Disease Center. The study, published in the September 15, 2010, online issue of Neurology, the medical journal of the American Academy of Neurology, found that even the very early mild changes in memory that are much more common in old age than dementia are caused by the same brain lesions associated with Alzheimer's disease and other dementias.

"The very early mild cognitive changes once thought to be normal aging are really the first signs of progressive dementia, in particular Alzheimer's disease." said Robert S.Wilson, PhD, neuropsychologist at Rush University Medical Center. "The pathology in the brain related to Alzheimer's and other dementias has a much greater impact on in old age than we previously recognized."

The study involved over 350 nuns, priests and brothers who participated in Rush's Religious Orders Study and completed up to 13 years of annual cognitive testing. After death, the brains were examined for the lesions associated with dementia: neurofibrillary tangles, cerebral infarction (stroke), and Lewy bodies.

Researchers looked at the rate of change in cognitive function over time. The last four to five years of life showed a very rapid decline. The preceding years showed a much more gradual decline that would be described as normal aging.

As expected, pathologic lesions were related to the rapid decline, but researchers were somewhat surprised to find the pathology was very strongly predictive of the mild changes in cognitive function.

Higher tangle density adversely affected all forms of cognition at all trajectory points. Both Lewy bodies and stroke approximately doubled the rate of gradual , and almost no gradual decline was seen in the absence of lesions.

"Our study finds that Alzheimer's disease and related dementias are the root cause of virtually all loss of cognition and memory in old age. They aren't the only contributing factors; other factors affect how vulnerable we are to the pathology and to its effects. But the pathology does appear to be the main force that is driving cognitive decline in old age," said Wilson.

According to Wilson, recognizing that the earliest changes in are related to Alzheimer's pathology can lead to early diagnosis and will be critical information if a treatment is developed that can alter the pathologic course of the disease.

Explore further: Researchers have developed a computational framework for standardizing neuroscience data worldwide

Related Stories

Physical frailty may be linked to Alzheimer's disease

Aug 11, 2008

Physical frailty, which is common in older persons, may be related to Alzheimer's disease pathology, according to a study published in the August 12, 2008, issue of Neurology, the medical journal of the American Academy of Neu ...

Education protects against pre-Alzheimer's memory loss

Oct 20, 2008

ST. PAUL, Minn. – People with more education and more mentally demanding occupations may have protection against the memory loss that precedes Alzheimer's disease, according to a study published in the October 21, 2008, ...

Recommended for you

Researchers unlock mystery of skin's sensory abilities

20 hours ago

Humans' ability to detect the direction of movement of stimuli in their sensory world is critical to survival. Much of this stimuli detection comes from sight and sound, but little is known about how the ...

Tackling neurotransmission precision

Dec 18, 2014

Behind all motor, sensory and memory functions, calcium ions are in the brain, making those functions possible. Yet neuroscientists do not entirely understand how fast calcium ions reach their targets inside ...

User comments : 0

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.