Posts Tagged ‘cognitive psychology’

Default Network, System 1 Processing, and Alzheimer’s Disease (AD)

May 8, 2019

An earlier healthy memory blog post promised more about the default mode network. That post identified similarities between the default mode network and Kahneman’s System 1 Processing. Kahneman’s System 1 processing is important in that HM thinks that too heavy a use of System 1 processing at the expense of System 2 processing, which is active thinking, increases the risk for AD.

The simplest distinction between the two terms is that Kahneman is a cognitive psychologist and his two process view of of cognitive processes comes from cognitive psychology. The default mode network comes from cognitive neuroscience. Default mode activity is identified via brain imaging. Although they might not be identical, that distinction awaits further research, it is clear that there is considerable overlap between the two.

In addition to brain atrophy, AD patients have abnormal high levels of proteins in different brain regions. In the medial temporal lobe, the accumulation of tau protein leads to neurofibrillary tangles. In cortical regions, such as the parietal cortex in early AD, the accumulation of amyloid-B protein leads to amyloid plaques. The neurofibrillary tangles in the medial temporal lobe and amyloid plaques in cortical regions can be assumed to disrupt neural processing in these regions.

Dr. Slotnick writes, “There is an influential hypothesis that were is a causal relationship between default network activity that leads to deposition of amyloid that results in atrophy and disrupted metabolic activity, which impairs long-term memory in AD patients. The regions in the default network are active when participants are not engaged in a task and include the dorsolateral prefrontal cortex, the medial prefrontal cortex, the inferior prefrontal cortex and the medial parietal cortex. In AD patients, amyloid deposition occurs in the same regions, which suggests the default network activity may lead to amyloid deposition. Dr. Slotnick suggests that perhaps higher level of amyloid deposition, which occurs in late AD patients, is necessary to produce atrophy in the frontal cortex.

Dr. Slotnick continues, “If high amyloid deposition is a causal factor in developing AD, older adults with low levels of amyloid should be at decreased risk for developing this disease. There is some evidence that cognitive engagement and exercise engagement throughout life may reduce the amyloid level in the brains of healthy older adults as a function of cognitive engagement, and this was compared to the cortical amyloid levels . Participants rated the frequency which they engaged in cognitively demanding tasks such as reading, writing, going to the library, or playing games at five different ages (6, 12, 18, 40, and their current age). Healthy older adults with greater cognitive engagement throughout their lifetime, as measured by the average cognitive activity at the five ages, had lower levels of amyloid in default network regions. Moreover, the healthy older adults in the lowest one-third of lifetime engagement had amyloid levels that were equivalent to AD patients, and the healthy older adults in the highest one-third of lifetime cognitive engagement had amyloid levels that were equivalent to young adults.

So maintaining a growth mindset, thinking critically, and learning new information provide double protection against AD. First, the reduction of troublesome amyloid levels. Second is the building of a cognitive reserve so that even if you develop amyloid plaque and neurofibrillary tangles you may not have the cognitive and behavior symptoms of AD.

Dr. Slotnick’s work is reported in an important book by Scott D. Slotnick titled “Cognitive Neuroscience of Memory.” The report on which Dr. Slotnick’s statements are based comes from
Buckner, R.L., Snyder, A.Z., Shannon, B.J., LaRossa, G. Sachs, R. Fotenos, A.F., Sheline, Y.I., Klunk, W.E., Mathis, C.A., Morris, J.C. & Mintun, M.A. (2005). Molecular, structural, and functional characterization of Alzheimer’s disease: Evidence for a relationship between default activity, amyloid, and memory. The Journal of Neuroscience, 25, 7709-7717.

© Douglas Griffith and healthymemory.wordpress.com, 2019. 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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Passing 73

May 6, 2019

Meaning that today HM is entering his 74th year. He engages in ikigai, the Japanese term referring to living a life with purpose, a meaningful life. His purpose, in addition to living a fulfilling life with his wife, is to learn and share his thoughts and knowledge with others. HM does this primarily through his blog healthymemory, which focuses on memory health and technology.

HM’s Ph.D is in cognitive psychology. That field has transitioned to cognitive neuroscience, a field of research and a term that did not exist when HM was awarded his Ph.D. HM is envious of today’s students. However, he is still fortunate enough to be able to keep abreast of current research and to relay relevant and meaningful research from this field to his readers.

What is most disturbing is the atmosphere of fear and hate that prevails today. It is ironic that technology, which had, and still has, a tremendous potential for spreading knowledge, now largely spreads disinformation, hatred, and fear.

HM understands why this is the case, but, unfortunately, he does not know how to counter it.

The problem can best be understood in terms of Kahneman’s Two Process Theory of cognition. In Nobel Lauerate Daniel Kahneman’s Two System View of Cognition. System 1, intuition, is our normal mode of processing and requires little or no attention. Unfortunately System 1 is largely governed by emotions. Fear and hate are System 1 processes. System 2, commonly referred to as thinking, requires our attention. One of the roles of System 2 is to monitor System 1. When we encounter something contradictory to what we believe, the brain sets off a distinct signal. It is easier to ignore this signal and to continue System 1 processing. To engage System 2 requires attentional resources to attempt to resolve the discrepancy and to seek further understanding. To put Kahneman’s ideas into the vernacular, System 2 involves thinking. System 1 is automatic and requires virtually no cognitive effort. Emotions are a System 1 process, as are identity based politics. Politics based on going with people who look like you requires no thinking yet provides social support.

Trump’s lying is ubiquitous. Odds are that anything he says is a lie. His entire candidacy was based on lies. So why is he popular? Identifying lies and correcting misinformation requires mental effort, System 2 processing. It is easier to be guided by emotions than to expend mental effort. The product of this cognitive miserliness is a stupidity pandemic.

Previous healthy memory posts have emphasized the enormous potential of technology. Today people, especially young people, are plugged in to their iPhones. Unfortunately, the end result is superficial processing. They get information expeditiously, but they are so consumed with staying in touch with updated information, that they have neither time nor attention left for meaningful System 2 processing. Unfortunately, technology, specifically social media, amplifies these bad effects, thus increasing misinformation, hatred and fear. Countering these bad effects requires implementing System 2 processes, that is thinking. A massive failure to do this enables Trump to build his politics on lies spreading hatred and fear.

As has been written in many previous healthy memory posts, System 2 processing will not only benefit politics, but will also decrease the probability of suffering from Alzheimer’s and dementia.

Personally, all this is upsetting. But HM believes it is essential to love one’s fellow humans. He tries to deal with this via meditation. Progress is both difficult and slow but it needs to be done. Hatred destroys the one who hates. So HM continues a daily struggle to be a better human being.

© Douglas Griffith and healthymemory.wordpress.com, 2019. 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.

What is Thought?

August 7, 2018

The question in the title is motivated by a book by British psychologist Charles Fernyhough titled “The Voices Within.” There have been psychologists who have argued that thought, solely or largely, consists of these voices within. This cannot be true because the frequencies of these voices varies largely amount individuals. We cannot readily argue that these people are not thinking. It can be argued that these voices within are tools for thinking as are images and symbols we mentally imagine. However, thought is something deeper, something that emerges from our unconscious minds.

HM has had the experience of being unable to recall the name of a friend, although he can recall related reams of information about this friend. How can this be? Later, the friend’s name pops into mind. How did this happen? And how did he know that what popped into his mind was the friend’s name? Psychology has very little to say about this, but knowledge ultimately resides in neural codes in our unconscious minds. When the name matched this neural code, it was recognized. But all this knowledge, all this information is stored in neural codes. When they are retrieved into consciousness is when the words become available and can be used for thinking.

When HM is writing a blog post, he has something he wants to say, but he is not yet able to articulate it. Gradually he retrieves information from memory, thinks about it, puts it into his computer, examines it, and massages it. He evaluates it, elaborates it, and makes changes. At some point he gets to the point where he either likes it or decides it is good enough given the time and the resources available. Essentially what he is evaluating is the correspondence between these external words and the neural codes in his unconscious mind.

Cognitive psychologists have increasingly realized the importance of the unconscious mind, and have developed sophisticated techniques for understanding the unconscious mind. But the major body of work needs to be done by neuroscientists, and that body of work is truly enormous.

© Douglas Griffith and healthymemory.wordpress.com, 2018. 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.

Psychology

April 30, 2017

Of all the skills needed for success, I believe that psychology is the most important.  Of course, being that HM is a psychologist, a degree of bias must be admitted.  Nevertheless HM shall make this argument.

Psychology is frequently confused with psychiatry.  Psychiatry is a medical specialty dealing with mental problems.  Clinical and some counseling psychologists also deal with mental problems, but they represent about half of all psychologists.  Other types of psychology are social psychology, industrial psychology, organizational psychology, engineering psychology, educational psychology, psychologists who work primarily with nonhuman organisms, and psychologists who work with humans.  HM is a cognitive psychologist meaning that he is interested in how we perceive, remember, learn, make decisions, form concepts, solve problems;  that is basically everything we do that involves our brains.

In “How to Fail At Almost Everything and Still Win Big” Adams devotes several pages to biases, heuristics, different types of effects, fallacies, illusory correlation and so forth.  Our cognitive processes are very complex, and they need to be understood as well as they can be understood.  We are constrained by a limited attentional capacity that must be understood.  Memory failures can usually be attributed to failures to pay attention, but we are bombarded by much more information than can be processed.  Memories change over time, and every time we recall a memory it changes.  Memories are highly fallible, yet we have a high degree of confidence in them. In short, we need to understand our minds as best we we can so that we are aware of the mistakes we are likely to make, and so that we can use our minds to best advantage.

Adams is writing about success and his examples are how a knowledge of psychology is key to success.  But given that education involves learning, should not students be provided an understanding of how we learn?  And given that education involves memory, should not an understanding of our memory systems be taught?  And should not learning and mnemonic techniques be taught to facilitate learning and memorization?  Should not students be taught problem solving techniques and the traps that can preclude solving problems?

Meditation is beneficial to both learning and emotional health, so should not meditation be taught and regularly practiced in schools?  Mindfulness training provides a basis for understanding why we differ and how best to interact with others who think or behave differently.  Disciplinary problems would largely disappear if both meditation and mindfulness were standard practices in schools.

Many businesses are providing for meditation and mindfulness to be incorporated into their business practices and many more businesses will be adding these practices in the future.  They might also want to add courses on human cognition that are relevant to their respective workplaces.

© Douglas Griffith and healthymemory.wordpress.com, 2017. 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 Review of The Brain

November 12, 2015

The Brain is a book by David Eagleman.  The subtitle is “The Story of You.”  I gave the book 5 stars in my review on Amazon.  I wrote, “Anyone with a brain should read this book.  (Knowing) how the brain works is essential for the individual.  It also provides the basis for more effective government.”

The brain is the most important organ of the body (even though Woody Allen said it was his second favorite organ).  It informs us who we are.  Growing the brain provides us with additional knowledge and know how.  This much should be obvious.  However, when I see the problems we have, many of them are due to a lack of knowledge as to how our brain works.  That is what I meant by writing, “provides the basis for more effective government.

Eagleman writes, “Your brain is a relentless shapeshifter, constantly rewriting its own circuitry—and because your experiences are unique, so are the vast detailed patterns in your neural networks.  Because they continue to change your whole life, your identity is a moving target;  it never reaches an endpoint.  Eagleman explains how the brain develops and why the teen brain is set up to take risks.  Moving from childhood into adolescence, the brain shows an increasing response to rewards in areas related to pleasure seeking such as the nucleus accumbens.  In deems this activity is as high as in adults but activity in the orbitofrontal cortex, which is important  for executive decision making, attention, and simulating future experiences, is still about the same in teens as it is in children.  In fact, the prefrontal cortex, which is important for executive decisions, dos not mature until the mide-twenties, which provides adequate time for ruining our lives.  The brain continues to change physically as we learn new skills and information and memories themselves change each time they are summoned.  Memories are highly fallible and can be easily changed, which are facts not generally recognized by courts of law.

Eagleman includes a study of nuns who are willing to provide their brains for study after they die.  The nuns are tested while they are living and then autopsies are provided after they die.  They have found brains that are wracked by the defining neurofibril tangles and amyloid plaques of Alzheimer’s, but these  nuns never exhibited any of the symptoms of Alzheimer’s and remained mentally sharp until they died.  The nuns are not unique, other autopsies on other populations have resulted in similar findings.  The nuns interacted with each other, they had growth mindsets, and the meditated with prayer, presumably continuing to develop a cognitive reserve.  Yet Alzheimer’s research is focused on finding drugs to destroy or inhibit the growth of these physical symptoms as well as tests to detect the early development of these symptoms.  There are no drugs that can cure Alzheimer’s, and there are knowledgeable scientists who believe that there never will be such drugs (See the healthy memory blog post “The Myth of Alzheimer’s).  All that drugs can do is to slow the progress of Alzheimer’s.  In my view all this does is to prolong the suffering.

People need to understand that reality is an illusion.  True there is a real physical world, but we learn of this world via our senses, which are used to build up mental models.  Moreover, each of us has different views of this world, one that changes, or should change with experience and learning.  People who fail to understand this are naive realists, and one of the reasons for the problems of the world is the existence of these naive realists.  Eagleman explains how this learning takes place.   He notes that the brain is like a city.  When one looks at a city one sees buildings, roads, structures and so forth, but to find out where businesses are and how the city actually functions, it is due to interactions of different parts of the city.  The same is true of the brain.  It is a complicated structure that operates by intercommunicates among the different elements.  Most of these intercommunicates are unconscious, but some raise to he level of consciousness.

It is interesting to note that the visual system has some connections that feed forward and others that feed backwards.  What makes this interesting is that the ratio of connections feeding backward are ten times those of feeding forward.  This provides a strong indication how much we know bears on what we actually see.  Expectations weigh heavily on what we see.

Our brain is a storyteller.  It serves us narratives that bear on what we believe.  Ascertaining truth usually entails the critical thinking about different narratives.

We are unaware of the vast majority of the activity in our brains.  It remains below our level of consciousness, so one may well ask, who is in control.  A good way of thinking about this is to regard our consciousness as an executive office that makes important decisions.  There are some who believe that our conscious minds are only along for the ride, but I am not one of them (see the healthy memory blog post, “Free Will”).

The healthy memory blog argues that the memory is a device for time travel and Eagleman agrees.  It is a device that travels back to the past to plan for the future.  This involves generating scenarios for what might happen in the future.  The same parts of the brain that are involved in remembering are used in imaging alternative  futures.

Eagleman writes,”Although we typically feel independent, each of our brains operates in a rich web of interactions with one another—so much that we can plausibly look at the accomplishments of our species as the deeds of a single, shifting mega-organism.”  A subsequent healthy memory blog post will expound more on this topic.

The final chapter is titled “Who Will We Be?” and addresses the possibility of our transcending our biological selves.  This is an interesting chapter, but we might be constrained by our limited levels of attention.  We can only consciously attend to several items at once.  We become skilled or fluent via many hours of practice.  Can this bottleneck be transcended?  This question is key to the answer to the question of whether we can transcend our biological selves.

There is a PBS series based on this book, that I strongly recommend.  I recommend both reading the book at watching the series multiple times.  Understanding our brains is of paramount importance.