Posts Tagged ‘Myth’

How Do People Circumvent Amyloid Plaque and Neurofibrillary Tangles

July 28, 2015

As has been mentioned in previous healthy memory blog posts, autopsies have found corpses whose brains have been wreaked with amyloid plaque and neurofibrillary tangles, yet who never exhibited any symptoms or behaviors indicating Alzheimer’s.  Yet it is these very substances that provide for a definitive diagnosis of Alzheimer’s.  So at best they are a necessary, but not a sufficient, condition for Alzheimer’s.  See the healthy memory blog post, “The Myth of Alzheimer’s” to learn whether this is actually a disease and whether a drug solution to this problem is possible.  Unfortunately, the money is in the drugs, so that’s where the effort is concentrated.

The explanation offered is that these people with the substances defining the disease, but without the symptoms of the disease, have build up a cognitive reserve.  In other words their brains have a reserve to draw upon that allow them to circumvent the symptoms of the disease.  This is very likely true and this provides strong evidence that we should start early and continue to build this cognitive reserve throughout our lives.

However, I believe that something else is at work, and I believe that is neuroplasticity.  Neuroplasticity refers the ability for the nervous to rebuild and repair itself.  The existence of neuroplasticity is a fairly new finding.  When I was a graduate student the dogma was that neural damage could not be repaired, and this dogma remained in effect until fairly recently.

To learn more about neuroplasticity enter “neuroplasticity” into the healthy memory blog search box.  I wish more research would be put into the preventive and curative effects of neuoplasticity.  As you’ll see if you read or reread “The Myth of Alzheimer’s,” some knowledgeable people do not believe that a drug cure is possible, but that there are other effective avenues to pursue regarding Alzheimer’s or dementia.

© Douglas Griffith and healthymemory.wordpress.com, 2015. Unauthorized use and/or duplication of this material without express and written permission from this blog’s author and/or owner is strictly prohibited. Excerpts and links may be used, provided that full and clear credit is given to Douglas Griffith and healthymemory.wordpress.com with appropriate and specific direction to the original content.

A Phrase That Should Be Considered Obscene

October 12, 2014

That phrase is “senior moment.” First of all, it is an instance of ageism, which is just as pernicious as racism or any of the other “isms.” But more importantly, it is inaccurate. Regular readers of the healthymemory blog post, should have immediately recognized this inaccuracy. This topic has been broached in many posts. Consider only the immediately preceding post, “You Can Teach an Old Dog New Tricks, “ and an earlier post “The Myth of Cognitive Decline. New neurons are continually being generated as we age, and the brain is rewiring itself to account for changes as we age. Any apparent slowness or difficulty in retrieving information is due to the massive amounts of information storage and learning that has occurred during these additional years.

Unfortunately, sometimes this phrase is used as a polite excuse for being slow to recall. Perhaps a substitute phrase should be “due to extreme amounts of information (or perhaps, wisdom, depending how strongly one wishes to push it) there has been a delay in accessing this information. I’ll get back with you when it becomes available.”

The worse use of the phrase is when it becomes a belief. It is easy to think that cognitive decline is inevitable and to accept it. Not only does such a belief become a self-fulfilling prophecy, but it accelerates the rate of any decline. We do experience physical decline, but to use any noticeable decline as an excuse for giving up physical activity just increases the rate of decline. We must push ourselves to continue activities as we age.

Similarly, we must not decrease cognitive activities or avoid cognitive challenges as we age. There is reason to believe that we can not only slow the decline, but that we can also continue cognitive growth as we age. We must remain cognitively and socially active as we age and not beg off with the excuse of “senior moments.”

Remember that autopsies have revealed brains wracked with the neurofibril tangles and amyloid plaques that are regarded as the signatures for Alzheimer’s, but whose owners never evidenced any symptoms of Alzheimer’s when they were alive.

© Douglas Griffith and healthymemory.wordpress.com, 2014. Unauthorized use and/or duplication of this material without express and written permission from this blog’s author and/or owner is strictly prohibited. Excerpts and links may be used, provided that full and clear credit is given to Douglas Griffith and healthymemory.wordpress.com with appropriate and specific direction to the original content.

Why Our Brains Never Fill Up

September 7, 2014

The answer to this question can be found in the September/October 2012 Scientific American Mind in the article “Making New Memories.” Actually readers of the healthymemory blog should already know the answer to this question. The answer is neurogenesis. Neurogenesis is a process that does not stop when we age. It continues until we die. Now the hippocampus is one of only two sites in the adult brain were new neurons grow. They grow in the region of the hippocampus called the dentate gyrus. The rate of neurogenesis in the hippocampus is estimated to be 1400 neurons a day. This is important as the hippocampus plays a central role in memory.

There is an expression, neurons that fire together wire together. This expression captures the concept of the Canadian psychologist Donald O. Hebb’s Cell Assembly Theory. One problem has been that most cell assemblies are associated to other cell assemblies and so forth and so forth. Although this is the basis for cognitive enrichment, how are all these cell assemblies distinguished? In 1995 the psychologists James L. McClelland, Randall C. O’Reilley, and Bruce L. McNaughton proposed that the cerebral cortex forges these connections and the hippocampus tags cell assemblies so that distinct memories are filed away. But where did these new neurons come from to keep these memories distinct? At that time it was thought that we only have the neurons with which we are born. We even lose many of those neurons very early in life. It was not until the late 1990’s that neurogenesis was discovered. Subsequent research has indicated that this neurogenesis continues until we die. So these neurons are being created just when they are most needed! See the healthymemory blog post, “What is Neuroplasticity and How Does It Work.”

So key to keeping and maintaining your memory is to build a healthy hippocampus. To learn how to build your hippocampus, see the healthymemory blog post, “”To Improve Your Memory, Build Your Hippocampus.”

Growing old is no excuse for old dogs not learning new tricks. Growing old is no excuse for not continuing to learn and do new things. Cognitive decline is a myth. See the healthymemory blog post, “The Myth of Cognitive Decline.” Cognition might slow down as we age and, although there are some biological factors underlying part of this, the brain adapts. Apparent slowness and occasional forgetfulness, so called “senior moments,” are likely the result of the vast amounts of information that are stored in the elderly brain. This is especially true of the elderly brain that has spent a lifetime growing and learning. It takes more time to process and retrieve information from this enlarged network. Apparent slowness might well be due to cognitive richness rather than cognitive decline.

© Douglas Griffith and healthymemory.wordpress.com, 2014. Unauthorized use and/or duplication of this material without express and written permission from this blog’s author and/or owner is strictly prohibited. Excerpts and links may be used, provided that full and clear credit is given to Douglas Griffith and healthymemory.wordpress.com with appropriate and specific direction to the original content.

The Myth of Alzheimer’s

August 28, 2011

The Myth of Alzheimer’s by Peter J. Whitehouse, M.D., Ph.D. and Daniel George, M.Sc. is an important book. The myth is that Alzheimer’s is a single disease, and that a drug will be developed that serves as a silver bullet and eradicate Alzheimer’s. Whitehouse is no crackpot. He knows whereof he speaks. Note that he has a Ph.D and an M.D. Although he is now working as a clinician, he spent many years at the forefront of research on drugs to mitigate or eradicate Alzheimer’s disease (AD). He was a prominent researcher who was well funded and promoted by drug companies. When he became convinced that a cure for Alzheimer’s was not forthcoming, he turned his efforts to treatment.

Note that a definitive diagnosis of Alzheimer’s, even with today’s brain imaging technology cannot be made while the patient is living. It must await the autopsy of the individual. The presence of amyloid plaques and neurofibrillary tangles would confirm a diagnosis of Alzheimer’s. The problem is that autopsies of people who have shown no indications of cognitive impairments have also shown the presence of amyloid plaques and neurofibrillary tangles. Most drug treatments have been targeted to remove or mitigate these amyloid plaques or neurofibrillary tangles. Although some drug treatments have been able to slow the progression of Alzheimer’s in some people, these drugs typically have side effects and cannot prevent its progression. In some cases they just slow the occurrence of death, which prevents release from this degraded state. In an interesting history of the disease it becomes clear that its founder, Alois Alzheimer, had doubts that this was a distinct disease and that scientific competition forced Alzheimer’s employer to convince Alzheimer to call it a distinct disease.

The thesis of the book is best captured from the following excerpt from page 220, …”It is unlikely that there will ever be a panacea for brain aging and baby boomers should not rely on extraordinary advancements being made in their lifetimes besides the promises of the AD empire that make their way into our headlines. Our attention must begin shifting from mythical cure to hard-earned prevention, from expecting a symptomatic treatment for AD to choosing behaviors that may delay the effects “of cognitve decline over the course of our lives.” Many, if not most, of the behaviors he discusses have been mentioned and advocated in the Healthymemory Blog.

The book provides a superb tutorial on the history of AD from its unassuming beginnings to the development of an AD Empire. It reviews the science underlying AD and the role of genetics in AD. It discusses past and present treatments for AD. It explains how to identify someone who might need a prescription for memory loss, and how to prepare for a doctor’s visit. It presents a new model for living with brain aging as well as a prescription for successful aging across the life span. An epilogue is titled “Thinking Like a Mountain: The Future of Aging.”

This is an important and interesting book for everyone, but especially for us Baby Boomers.