Archive for May, 2014

A Neurocognitive Framework for Ameliorating Cognitive Aging

May 31, 2014

This post is taken from a chapter with the same name, “Ameliorating Cognitive Aging:  A Neurocognitive Framework”  in the book Nurturing the Older Brain and Mind  by Greenwood and Parasuraman.  Brain aging needs to be dealt with.  There is cortical shrinkage and there are white matter changes.  The shrinkage and white matter changes have a small effect on cognitive performance.  Neurotransmitter  dysfunction is a matter of more concern.  Then there are genetic factors.  First of all there is the genotype, then the gene expression from this genotype.  Although some individuals suffer from a genetic predisposition to dementia, these are not deterministic, but rather predispositions.  That is, given such and such experiences or external factors, the likelihood of dementia increases.  Then there are epigenetics, which determine how the genes are actuated.  Epigenetics are affected  by lifestyle and experiential factors such that favorable factors can enhance the probability of favorable genetic readouts.

Turning to the lifestyle and experiential factors, education, exercise, diet, learning and training, and combinations of these factors enhance the likelihood of good cognitive performance throughout one’s lifespan.   More details on these individual factors will be provided in subsequent healthymemory blog posts.

Then there is the matter of neuronal plasticity that includes neurogenesis, synaptogenesis, dendritic arborization, and network reorganization.   An example of network reorganization is the greater use of both hemispheres as we age.  When I was a graduate student I was taught that our nervous system was fixed and could not be modified when damaged or was damaged to aging.  Fortunately, what I was taught as a graduate student has been found to be woefully in error.  These processes can occur well into old age.  But they need to be activated by new learning and experiences for them to occur.

Next there is cognitive plasticity.  Top-down processing strategies can be used to make better use of our accumulated knowledge.  Then there are our well-developed prefrontal lobes for effective executive functioning.

I have often written of the importance of building a cognitive reserve.  Although advice was provided as to how to build one’s cognitive reserve, Greenwood and Parasuraman have provided the first neurocognitive framework to explain how this occurs.

© 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.

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An Important Book for All to Read

May 26, 2014

And that book is Nurturing the Older Brain and Mind by Pamela M. Greenwood and Raja Parasuraman of George Mason University.  The book is an extensive review of the literature on the older brain and mind in general, and on Alzheimer’s and dementia, in particular.  Although younger people might think this book is only for us BabyBoomers that would be WRONG WRONG WRONG!  First of all, the magnitude of the problem must be considered.  As people age the probability of suffering  Alzheimer’s increases and with aging populations it will soon reach epidemic proportions.  Hopes for drug cures or preventative vaccines are slim (see the healthy memory blog posts, “The Myth of Alzheimer’s” and “Sigmund Freud and Alzheimer’s Disease”).   Moreover actions you take now can reduce the likelihood of suffering from Alzheimer’s or dementia.  If you have parents, there are things they can do to reduce the likelihood of suffering from Alzheimer’s or dementia.  And if you have children, there are things that both you and your children can do to reduce the likelihood of Alzheimer’s and dementia.  These “activities” or “things” are described in Nurturing the Older Brain and Mind.

Greenwood and Parasuraman note that although the brain might age, cognitive aging is neither universal nor inevitable.  Most individuals do not show a decline in cognitive functioning in old age, even though the probability of suffering such a cognitive decline increases as we age.  Moreover it has been noted in many healthymemory blog posts that there are many individuals who do not suffer cognitive decline in spite of the tell-tale amyloid plaque and neurofibril tangles of Alzheimer’s.  The only explanation of this fact has been that these people have developed a cognitive reserve.  Greenwood and Parasuraman present a neurocognitive framework to describe how this might be done.

Nurtuiing the Older Brain and Mind is a  scholarly work of the highest order reviewing an extensive research literature on the topic including both human and non-human species.  Nevertheless, I believe that it is written on a level where it should be accessible to the general reader.  Even if it takes a bit of a reach for the general reader, it is a reach well worth taking.  Although the healthymemory blog will draw heavily on this work, there is no way I can even hope of doing it justice.

© 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 only criticism I have of this work is that it does not address mindfulness, although I do understand why it was not addressed.  Part of the reason can be found in the immediately preceding blog post on random controlled trials or random clinical trials (RCTs).  The researchers do not regard the research on mindfulness as being significantly “rigorous.”  I remember when I was a graduate student there was a debate on whether we humans can control our autonomic nervous systems with out minds (heart rate, for example).  Now there were people in the east who were highly trained meditators who were able to do this.  Nevertheless, most psychologists would not accept this conclusion unless they could train someone to do it in a psychological laboratory.  They regarded these meditators as using some sort of “trick.”  Well the same thing has been said of mnemonic techniques, but these mnemonic techniques not only enhance memory, but also reveal important insights into how memory works.  Similarly mindfulness research will provide practical insights into how we can control our minds and our bodies.  These skills will be central not only to preserving cognitive functioning, but also to enhancing cognitive functioning.   I predict that mindfulness will play an increasingly strong role in nurturing the older brain and mind.

Randomized Control Trials, Mindfulness, and Meditation

May 24, 2014

The gold standard for evaluative research is the randomized control trial (RCT).  In RCTs subjects are assigned randomly to different experimental conditions.   Typically untreated control groups and placebo control groups are included.  Absent this random assignment, biases could be introduced into the study.  Statistical tests are administered on the data after it has been collected to estimate the likelihood that any differences are due to chance.

Conclusions are based on the populations from which the sample groups were drawn.  The conclusions are made to the populations from which these samples were drawn.  So if you are not  a member of this population, you cannot conclude that the conclusions are relevant to you.  You should also realize that the conclusions are not for you personally.   So even if you belong to a population it is possible that your responses to the treatment would have differed due to some genetic or experiential factor unique to you.

You will come across studies that conclude that mindfulness or certain types of meditation do not work or produce certain results.  You need to be skeptical regarding these conclusions.  First of all, it is quite likely that individuals can be found for whom these practices work.  But when reading about experiments you need to consider what was the length of the training period.  It is quite possible that the training period was insufficient.  It is also possible that the training was inadequate or wrong.  Then, there is also a matter of individual commitment.  Unlike a medical trial where some substance is provided, mindfulness practices require the commitment of the participant to the practice of mindfulness.  Half-hearted or skeptical participants are unlikely to participate.

So be skeptical of research on mindfulness or particular types of meditation that address the general question of whether it works.  That is a meaningless question.  However research into the specific benefits, physiological, brain activity or brain changes is informative.  What is especially informative is research into specific regimens of training and practice along with the resulting benefits.  And always be cognizant that you are an individual and that your results might very well differ.

© 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.

Limits to Human Understanding

May 20, 2014

This blog post was motivated by an article in the New Scientist1, “Higher State of Mind” by Douglas Heaven.  It raised the question of limits to human understanding, a topic of longstanding interest to myself.  The article reviews two paths Artificial Intelligence has taken.  One approach involved rule-based programming.  Typically the objective here was to model human information processing with the goal of having the computer “think” like a human.  This approach proved quite valuable in the development of cognitive science, as it identified problems that needed to be addressed in the development of theories and models of human information processing.   Unfortunately, it was not very successful in solving complex computational problems.
The second approach eschewed the modeling of the human and focused on developing computational solutions to difficult problems.  Machines were programed to learn and to compute statistical correlations  and inferences by studying patterns in vast amounts of data.  Neural nets were developed that successfully solved a large variety of complex computational problems.  However, although the developers of these neural nets could describe the neural net they themselves had programmed, they could not understand  how the conclusion was made.  Although they can solve a problem, they are unable to truly understand the problem.  So, there are areas of expertise where machines can be said to know not only more than we do, but also know more than we are capable of understanding.  In other words, what we can understand  may be constrained by our biological limitations.
So, what does the future hold for us?  There is an optimistic scenario and a pessimistic scenario.  According to Kurzweil a singularity will be achieved by transcending biology and we shall augment ourselves with genetic alterations,  nanotechnolgy, and machine learning.  He sees a time when we shall become immortal.  In fact, he thinks that this singularity is close enough that he is doing everything to extend his life so that he shall achieve this immortality.  This notion of a singularity was first introduced in the fifties by the mathematician John von Neuman.
A pessimistic scenario has been sketched  out by Bill Joy.  I find his name  a bit ironic.  He has written a piece titled, “Why the Future Doesn’t Need Us”  where he argues that technology might be making us an endangered species.
So these are two extremes.  A somewhat less extreme scenario was outlined in the movie, Collosus:  the Forbin Project, which was based on a novel by Dennis Feltham Jones, Collus.  The story takes place during the cold war with the confrontation between the United States and the Soviet Union.  The United States has built a complex sophisticated computer, the Collosus to manage the country’s defenses in the event of a nuclear war.  Shortly after the Collosus becomes operational, it established contact with a similar computer built by the Soviet Union.  These two systems agree that humans are not intelligent enough to manage their own affairs, so they eventually hey take over the control of the world.
So what does the future hold for us?  Who knows?

© 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.

Einstein, Quantum Mechanics, and the Human Mind

May 17, 2014

This post was motivated by my reading of the Cover Story, State of Mind, by Matthew Chalmers in the 10 May 2014 issue of The New Scientist.  Einstein’s Theory of General  Relativity accounts for a large amount of the behavior of the physical world.  It is deterministic, predicting what follows what.  Quantum mechanics accounts for the physical behavior on a very small scale and accounts for subatomic behavior.  However, at this small scale, the behavior is not strictly determined.  It is probabilistic.  Moreover, Heisenberg’s uncertainty principle states that the location and the velocity cannot be determined at the same time.  One or the other can be measured, but the measurement itself produces change.  Einstein could not accept quantum physics.  He said that God does not play dice with the universe.  Yet quantum physics works quite well, and a fair amount of modern technology results from quantum physics.

In the quantum world objects exist in a fuzzy combination of states, and the very act of measuring them forces them to adopt a specific state.  Einstein spent the latter part of his career trying to reconcile his theory with quantum physics.  Einstein, with all his genius, failed to do so.  Many prominent physicists have continued Einstein’s quest, but all have failed to do so.

Now there is a theory that reconciles the two different theories, but it does not do so in the physical world, but rather in our minds.  It is called quantum bayesianism (QBism).  Thomas Bayes formulated a theorem named after him that computes how probability changes after new information is added.  There is a Bayesian approach to statistics that incorporates the concept of subjective probability.  This approach is quite popular with cognitive psychologists.  QBism states that quantum states are all in our minds.  They are just a mental tool that we use to understand our variable experience in the world.

This reminds me of an experience I had earlier in my life.  This was with a bright young physicist who had difficulty coming to grips with the concept that light could be regarded as waves, or as discrete particles of photons.  As a psychologist, this had never been a problem for me as I did not, and still not, think that we have direct contact with the physical world.  We learn about the physical world through our senses from which we build mental models of external reality.   I have since learned that the 18th century philosopher Kant held the same or a similar notion.  He thought that there is no direct experience of things, and that we construct in our minds models from sensory inputs.  In the case of light, wave theories are the best way to think about some phenomena, and particle theories are the best way to think about other phenomena   In the case of physics, Einstein provides the best models for thinking about the larger physical world, whereas quantum mechanics provides the best models for thinking about the subatomic world.
A good example of this categorical perception can be found in the processing of language.
There is a phoneme in both Korean and Japanese that falls half way between an r sound and an l sound.  This sound is quite clear to Koreans and Japanese, but I always hear either an r or an l.  Difficulty arises on their side when they are speaking and “ I love you” comes out as “I rove you.”
Perhaps with enough training I can overcome this faulty perception.  Certainly Japanese and Koreans who become fluent in English certainly do.

Returning to the world of physics, it is possible that some theoretical physicist will develop a means of reconciling the two theories.  And that theory might provide deeper insight into the discipline of physics, although it is highly doubtful that I shall be able to understand it.  In any case, this is not something for the rest of us to be concerned with as our minds shall  continue to construct mental models as they are needed.

© 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 People Play Slot Machines

May 13, 2014

Regular readers of the healthymemory blog should know that its author believes that it is foolish to play casino games.  Casino games are structured such that the odds always favor the casino, so although there might be winnings in the short run, there is no way there will be winnings in the long run.  In the case of slot machines, they’re usually set up to for a 10% share of the play.  So if you spend $100 on a slot machine, you are likely to lose $10.
So I was quite pleased to come upon an article in The Economist1  that addressed this topic.  Slot machines are tweaked within the realm of randomness  such that “near wins” of two out of three symbols appear quite often.  The notion is that players are so pepped by “almost” winning that they are stimulated to carry on playing.
Brain imaging techniques were used by Dymond of Swansea University in Britain and his colleagues to try to determine why this is the case.  functional Magnetic Resonance Imaging (fMRI) , which show which part of the brain are especially active at any given moment was one technique.  A second technique was magnetoencephalography (MEG) measure the electrical nature of that activity.   These two techniques enabled the building of a map for each research participant’s brain as she played on a simulated slot machine.
The focus was on the theta response, the electrical activity in the 4-7 Hz range.  Previous research has identified this response to be related to the processing of experiences of winning and losing.  There were two groups in the experiment.  One group consisted of participants addicted to playing slot machines.  A second group consisted of non-gamblers.  All research participants showed high theta responses to wins and low ones to loses.  The responses to near wins showed similar responses with the exception of the right orbitofrontal cortex.  The theta activity in the right orbitofrontal cortex of the gamblers showed spikes of about 32% and 27% in their theta waves for wins and near wins respectively.  Non-gamblers showed similar responses for wins, but only a 13% increase in theta wave activity for near wins.
This provides a good example of where your mind needs to control your brain.  Compulsive gamblers should realize that they are compulsive due to their brain responses and adjust their behaviors accordingly.  They need to realize that they are competing against a machine that has been cleverly designed go make them believe they are going to win, when in reality, they will lose in the end.  In other words, their minds need to overrule their brains.

© 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 Wheel of Awareness

May 10, 2014

The Wheel of Awareness can be found in Dr. Dan Siegel’s Pocket Guide to Interpersonal NeuroBiology.  The purpose of this wheel of awareness is to provide a map to guide meditation.  This map was developed by Dr. Siegel to guide meditation independent of any specific religious practice.    At the center of this hub is the awareness of the meditator.  There are four spokes going out of the hub to the rim of the wheel.  One goes out to exteroception, the awareness of external inputs to our five senses..  The second spoke goes out to interoception, the awareness of feelings internal to our bodies.   The third spoke goes out to mental activity.  The fourth spoke goes out to interpersonal relationships.  The purpose of the wheel is to guide awareness  so that important issues are not bypassed or overlooked.
So the meditator can place awareness on  each of the five senses and try to be consciously aware of everything on each sense to the exclusion of everything else.  There is an exercise that can be done with a raisin.  First the raisin is examined visually.  Then the raisin is felt, perhaps with the eyes closed.  Then the raisin is sniffed.  Next the raisin is placed in the mouth.  In addition to tasting the raisin, the texture of the raisin would be felt.  Finally, when the raisin is swallowed, it’s progress down the alimentary canal would be followed.
Now for interoception the focus is on one’s internal bodily feelings.  That is, how does one feel internally?  Any complaints from vital organs, muscles, or nerves?
Mental activity covers a lot of ground.  What thoughts are coming to mind and why.  Here is where one thinks about one’s own thinking.  One question is whether I am thinking when I say or do certain things, or are these automatic responses from my System 1 processes (Kahneman).  Are there biases  in my thinking of which I am unaware?
The fourth spoke is concerned with interpersonal relationships.  How are they going?   If there are problems, they can be pondered for understanding and possible solutions.
Dr. Siegel says that this is about a twenty minute practice, and if time is a constraint, perhaps it can be divided into five minutes per spoke done on consecutive days.
As the hub becomes stronger with individual practice we can imagine that part of the neural correlate of the hub, the middle prefrontal region, also becomes synaptically enhanced as well.   One when becomes advanced meditating with the wheel the person can focus a spoke back on the hub as well.  “Bending the spoke, in the mind’s eye, back towards the hub enables people to experience first hand what direct awareness of awareness itself feels like1.
Information and exercises on the Wheel of Awareness, along with other resources can be found on Dr. Siegel’s website, http://www.drdsiegel.com.

© 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.

Passing 68

May 6, 2014

I am 68 today, and I am still gainfully employed.  Although I could retire, the reason that I’m not retired is that my foremost goal is to have a healthy memory.  Data show a correlation between the age of retirement and the age of onset for Alzheimer’s.  The reason for this is that my job has me engage in the activities that foster the building of a cognitive reserve.  For more information on the cognitive reserve go to the healthy memory blog post “REST, Epigenesis, Neuroplasticity, Cognitive Reserve, and Alzheimer’s.”  Moreover, there is also the incentive of a paycheck.  And I still have the satisfaction of contributing to society.

The only factor that would make me consider moving from my current job was if there was a different position or activity in which I thought I could make a larger contribution to society.  I shall extend every effort to continue to be cognitively, socially, and physically engaged.  As long as I live I shall have a growth mindset.

Unfortunately, there is a downside to aging.  My parents, my brother, and all my aunts and uncles have passed away.  I have also lost contact with most of my cousins.  I had been planning on attending my 50th High School Class Reunion this June, but four of my closest friends in that class have already passed away.  I fear that attending this reunion would be too painful.

© 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.

 

A Much Needed App

May 3, 2014

The Metro Section of the April 20th Washington Post published an article written by Ashley Halsey III.   Titled “Curbing distracted teen drivers”  it was about an app that prevents its use while driving. These phones have sensors that detect motion and shut down when motion is detected. I found it interesting that the article only wrote about teen drivers, as if they were the only ones distracted by cell phone use.  Readers of the Healthymemory Blog should remember that there have been many blog posts about the dangers of cell use while driving.  Laws passed to reduce these dangers, the hands-free laws, are irrelevant because the hands are not the issue.  It is precious attention that is distracted that causes accidents.   Estimates have indicated that speaking on a cell phone while driving is comparable to driving over the legal limit for intoxication, 0.08 BAC in most states.  The degradation when texting is even worse. Realize that when you use a cell phone you are not just putting yourself and your passengers at risk. There are other drivers and pedestrians.   An automobile is a lethal weapon and can kill in addition to crippling and maiming.

I recently purchased a new dumb phone.  I was pleased to read a message on the back of the phone that warned about the dangers of its use while driving.   Some of the apps do more than just shut down when motion is detected.  They will also send messages to parents or employers.

I think there should be a law mandating that all cell phones have this app.  It would save a significant number of lives.  I, for one, would feel much safer.  People who regard this as an inconvenience should realize that we lived many years without these devices.