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Showing posts with label aging. Show all posts
Showing posts with label aging. Show all posts

Monday, February 03, 2020

Lifestyles that Promote Living Longer and Better



People in many parts of the world are living longer, due largely to improvements in medicine and healthier lifestyle afforded by less poverty. The downside is that the longer one lives the more likely a debilitating disease will emerge, such as cardiovascular disease, cancer, diabetes, or Alzheimer's Disease. For many people, the important thing is not how long they live, but how long they can live without serious physical suffering.

Many studies have established that the incidence of the common debilitating diseases can be reduced or delayed by modifiable lifestyle factors. While genes can obviously affect one’s vulnerability to disease, genes may not be the primary factor in how long or how well one lives. This is suggested, for example, by one study of over 110,000 healthcare professionals (about 1/3 male, 2/3 female) that clearly showed the value of healthy lifestyles.

The investigators queried these subjects and categorized them according to five lifestyle criteria:

    Diet, as assessed using the Alternate Healthy Eating Index, with a score in the upper 40% indicating a healthy diet;
    Smoking (never vs ever);
    Moderate to vigorous physical activity (≥ 30 minutes/day);
    No alcohol consumption above 15 g/day for women, 30 g/day for men;
    Body mass index (18.5-24.9 kg/m2).

Women who met four of the five low-risk lifestyle factors lived 10 more years free of cancer, cardiovascular disease, and type 2 diabetes at 50 years than women who followed none of the low-risk factors. In men, the gain in disease-free life expectancy was near 8 years. In terms of total life expectancy, women in the low-risk group at age 50 showed an increase from 31.7 years to 41.1 and men increased their life span from 31.3 years to 39.4 years.

This large-scale study confirms what has been indicated by a host of earlier studies that healthy lifestyles involve proper diet, absence of smoking, low consumption of alcohol, substantial exercise, and a BMI in the range of 18.5-24.9 kg/m.2  Moreover, both women and men who have a healthy lifestyle have significantly more years in which they avoid crippling heart disease, cancer, and type 2 diabetes.

The largest impact was on reduced incidence of cardiovascular disease and diabetes in both women and men. The lifestyles that were most likely to increase the three major diseases were smoking and obesity, in both women and men. Perhaps beneficial effects would be magnified by more stringent healthy lifestyle criteria (for example, upper 10% of healthy diet or level of exercise).

Other posts on lifestyle and aging research have clearly identified other healthy factors, such as  the value of emotional well-being and reduced psychological stress. Anecdotes suggest that living a life of worthy purpose may also promote aging well and living longer, though apparently there is not much formal research on this possibility.

Though we have no direct control over our genes, most of us can largely control how we live our lives. The beneficial effects of healthy lifestyle on aging well and longevity surely include direct enhancement of organ function and indirect effects on gene expression. Healthy lifestyles will help you, as we say in Texas, "Go out with your boots on."

Source

Li, Yanping, et al. (2020). Healthy lifestyle and life expectancy free of cancer, cardiovascular disease, and type 2 diabetes: prospective cohort study, January 8, BMJ 2020; 368 doi: https://doi.org/10.1136/bmj.l6669

Tuesday, December 24, 2019

The Role of Learning in Religion, Part II


(Excerpted from the new book, Triune Brain, Triune Mind, Triune Worldview (Brighton Publishing)(available at Amazon and Barnes and Noble).
In part 1 of this series, I explained that what one is taught and chooses to learn about religion changes the biology of the brain. Changing brain biology creates a change in who and what you are as a person. This principle applies to everyone, religious or irreligious.


Here, I will explore specific ways in which we program our brains to accept and live religious ideas. Relevant learning principles include the self-programming by brains and neural plasticity. There are important implications of religious learning in child rearing and adult maturation. Religious instruction matters to who you have become and how you will be in the future.

The Self-programming Brain


Brains self-programfor better or worse. Much of this programming can occur unconsciously. Freud made his mark in history by showing how the unconscious mind is a reservoir of feelings, thoughts, and memories that we may not easily access. Freud called this mind “subconscious,” a term that has fallen out of favor, perhaps because so much happens during unconscious processing that this should not be considered as inferior function. After Freud, numerous scientific findings confirmed that a great deal of information processing occurs in the unconscious brain, even during anesthesia. I led one such study on visual processing in anesthetized monkeys.[1] Since then, numerous studies have shown in humans that the brain is quite active during sleep in consolidating the experiences of the preceding day into memory. The dream stages of sleep obviously reflect intense brain activity, much of which would likely exert programming influences. When we are awake, we deliberately program our brain by the choices we make of what to read or hear, who to hang out with, what environments we prefer, and what we do.
Even while still in the womb, the brain of a late-stage fetus is programming itself to recognize sounds of the mother's pulse and visceral gurgles and external sounds from voices and music. Pressure changes in the womb are registered. Fetal brain continually programs recognition of limbs and the ability to move limbs. At birth, the process accelerates. I remember how astonished I was to watch my month-old great granddaughter program herself. When awake, her eyes were open and constantly scanning the environment. You could just imagine her brain going click, click, click, as it detected and stored input.
All mental experience can have programming effects. These may create a bias. In some sense, what you have learned can hold you hostage. However, humans also have the ability to change how they have been programmed. All this applies to religion.

Neural Plasticity        


Minds can change, and when they do, brains can change. We know that brain structure and function change in young people as they mature through childhood into adults. Even adult brains change in response to sensory and cognitive experiences. Your brain cannot form memories without changing the synaptic structure and biochemistry needed to store the memory. Learning experiences stimulate growth of microscopically measurable dendritic spines that enable new synapse formation. The information learned at the synapse level exists in the form of a stored propensity to regenerate the nerve impulse pattern representation of the learned information. The changes in the synapse in response to new information are enzyme systems that synthesize and degrade neurotransmitters, storage of neurotransmitters in presynaptic vesicles, up-regulation of postsynaptic molecular receptors, and biochemical cascades triggered by the receptor binding.
The brain’s greatest capacity for change occurs in childhood. As the learning of childhood progresses, many synaptic connections form to help store the new learning. In fact, in the fetus, far more neurons and connections form than needed, and the development process dismantles the surplus. This seems to be a competitive selection process, called “neural Darwinism.” Neurons and connections that survive are the ones that seem most useful to the brain.
Adults generally seem to be constrained by their earlier learning, as described in the old saw, “You can’t teach old dogs new tricks.” Actually, you can. It is just harder and may take longer to develop the new connections.
Because of the hard wiring that occurs in childhood, an “inner-child” persists as a memory throughout life. This fact formed the basis for the ideas in the famous book, I’m O.K. Your O.K., which emphasized that adults may be held hostage to their inner childhood. That is a burden if the childhood experiences were troubling.
The religious teachings of children likewise can have a powerful lasting effect. For example, a study of ministers revealed that what they learned as children markedly affected their adult perceptions of God. If they had vague or limited teaching about God as a child, they tended as adults to view God as remote. If they had in-depth exposure to God ideas as a child, their adult view was of a more personal God.[2]
The brain’s ability to change itself allows it to be responsive to outside influence aimed at alleviating mental health problems such as anxiety, depression, obsessions, and distorted self-image. One clinical method of treatment, known as cognitive behavioral therapy (CBT), attempts to change undesired thinking patterns into more positive ones and preserve them as new memories. Studies involving religiously oriented CBT use scripture, prayer, and other religious practices to overcome negative thoughts and perceptions. One study improved patient coping skills by both religious and secular CBT approaches, but quicker results resulted from the religious approach.[3]

Child Rearing


Religious upbringing helps children develop value systems, thinking styles, emotional development, and pro-social behaviors.[4] In all religions, education about the faith focuses on children, and the effects tend to be lasting. Religious parents often go to great expense to have their children educated in religious schools, because this ensures proper religious instruction, inculcation of moral values, and presumably fewer sinful temptations. In modern American culture, where perhaps a majority of children grows up without a father in the home, religious education might help compensate for the absence of a normal family environment. Government education has fewer mechanisms than religion for compensating for absentee fathers.
The more religious parents are, the more creative and persistent their children are in schoolwork. These children tend to be more motivated to learn and more attentive. Religious conflict between parents or within the family may produce negative effects on children. The common lament about poor academic performance by U.S. schoolchildren might be due at least in part to the general decline of religious commitment by the parents and by school policies that keep religion out of the curriculum.
A problem with religious education of children is that a child's brain is not yet developed, and certain limitations of emotion, language, and intellect limit what you can teach a child about religion or anything else. Typically, most religions teach their doctrines differently to children than to adults. Moreover, all religions recognize that children usually are unable to have an adult understanding of religious faith. Saint Paul explained this in the famous quote, "When I was a child, I spoke as a child, I felt as a child, I thought as a child. Now that I have become a man, I have put away childish things" (1 Corinthians 13:11).
Whatever one's religion, religion tends to create a partially closed mindset that prevents learning positive things about another religion. This is a special problem with young people. A study of fourth-, fifth-, and sixth-grade students (half Catholic, half Jewish) revealed strong cultural bias. The middle- to upper-class students lived in the same city. Teachers judged them to be average or above average in reading ability. Yet, when the students read a straightforward passage about the religion to which they did not belong, their cultural bias frequently caused them to misunderstand the reading and make memory errors. This was religion-specific in that they showed no such confusion or memory errors when asked to read non-religious passages at the same fourth-grade level.[5] Why the confusion and memory errors? I suspect they were less motivated to be sufficiently attentive to reading about a religion they did not believe in.
Age 13 (12 for girls) is often considered the transition point, as is expressed in Jewish tradition of Bar Mitzvah, where children are expected to be able to follow religious commandments. Christian groups also often set 12 or 13 as ages when children become sufficiently adult, as expressed in "confirmation" ceremonies.
Such age markers fail to accommodate what neuroscience has revealed about the biology of childhood maturation. A child’s brain is poorly developed, even at 13. Multiple ways of measuring maturation indicate that the brain does not reach biological maturity until the mid-twenties. Moreover, beyond that, we can all mature still further through learning and life experience.
A variety of evidence confirms that many teenagers are rebellious and pursue high-risk, ill-advised behaviors. Scientific experiments support the conclusion that the teenage brain is not "normal"no surprise to parents. For example, teenagers and adults have spatiotemporal differences in brain electrical activity in the prefrontal cortex. Teenagers are less able to use their prefrontal cortex to control behavior, especially to inhibit a desired action.[6] The real-world consequence is often poor judgment and self-defeating behavior. These limitations of brain function surely affect how a teenager deals with religious beliefs and behavior.
Parents and teachers try to prevent and correct bad behavior in one of two ways: reward or punishment, carrot or stick. An interesting comparison of these options for young children revealed that reward for proper behavior is usually more effective. In particular, food rewards seem to be the most effective in children.[7] There may also be an effect of religious outlook. If a child thinks of God as harsh and punishing over sin, their sense of self-worth may be threatened, and their motive for repentance is mind-crippling fear, guilt, or shame. However, if they think of God as loving and forgiving, they may be more likely to respect themselves enough to want to become a better person.

Neural Development and Aging Influences


The best markers for brain maturation seem to be age-related changes in amounts of cortical white matter (fiber tracts) and grey matter (cells and their processes). One kind of MRI (diffusion tensor imaging) noninvasively measures the amounts of both white and gray matter. An extensive study of 387 subjects from age 3 to 27 reveal that male brains are up to 10% larger than females. That may simply reflect that males usually have larger bodies than females. Total brain volume peaks earlier in females (10.5 years) than in males (14.5 years). White matter increases progressively over the years, but with a steeper rate of increase in males. At all ages, males have more white matter than females. However, females have more white matter in the fiber tracts that connect the two hemispheres. Grey matter increases early on in both sexes, and then decreases,[8] presumably reflecting the pruning of neural processes and synapses that normally occurs with learning.
Brain size usually shrinks in the elderly. Most of this shrinkage probably occurs from shriveling the extent of dendritic trees. Staying mentally active in old age seems to arrest this shrinkage. Mental activity, especially learning, promotes the proliferation of dendritic trees even in the elderly. A negative factor is likely the cumulative effects of a lifetime of stress. Stress releases cortisol, which in continuous large amounts disrupts synaptogenesis and formation of dendritic proliferation. All these factors affect all aspects of our lives, no doubt including religiosity.

Religious Instruction


Teaching of religious doctrines may be explicit or presented less obviously in the form of environmental conditioning. There are two kinds of conditioning, “classical,” as with Pavlov’s salivating dogs, and “operant,” a positive reinforcement technique used to train animals.
As a religious example of classical conditioning, kneeling is a natural reaction of submission, but when coupled with a cue of "let us pray," can trigger the impulse to kneel. Church bells or well-known hymns make you think of God and church.
 Such cues are not involved in operant conditioning, where repeated reward for a given action causes a person to repeat that behavior. A religious example is that churchgoers attend faithfully because past participation was rewarding for them. If you believe that confessed sins are forgiven, then it is positively reinforcing to confess sin.
In typical religious environments, conditioning tends to be informal, and perhaps thereby less effective than it would be with the more systematic formal methods of conditioning. Religions do repeat their doctrines of heaven and hell, and, when paired with religious ritual, constitutes a kind of classical conditioning. Operant conditioning might be involved in the positive reinforcement that comes from thinking repeatedly about the joys of heaven, while negative reinforcement comes from thinking about the horrors of hell.
Operant conditioning occurs when people participating in worship service perceive a net positive.[9] C. S. Lewis, the famous Christian advocate, made it a point upon his religious conversion to attend worship service regularly because he found spiritual support, even though he did not like most of the hymns, and the preaching was done by intellectual inferiors.[10] In order to sustain attendance at worship service, a believer may need to gain increasing amounts of positive reinforcement. Akin to drug addiction, one can develop a tolerance to the same dose of positive reinforcement. If worship does not provide the reinforcement of growing spirituality, the religion may eventually be abandoned. The current state of decline of Christianity in Europe and the U.S. may testify to this phenomenon,
At what point does teaching morph into "brainwashing?" We might say that teaching becomes brainwashing when it occurs in a closed environment that does not include alternative views. Learning, and certainly brainwashing, creates measurable changes in brain, and the differences vary by gender. For example, memory of emotionally charged information caused distinctive brain-scan changes in the right amygdala of males, while in women the changes occur in the left amygdala.[11]
Some believers deliberately place themselves in environments designed for brainwashing, where there is minimal exposure to secular matters and maximal exposure to religious thinking and practice. Examples include Catholic monasteries and nunneries or Muslim madrassas. People who commit to such environments may do so for different reasons, but a common denominator may be the desire to reduce secular temptations and gain some measure of "insurance" for God's favor. However, that insurance may be jeopardized if those people remain cloistered and do not reach out to the suffering masses.
The best way to avoid sin is to avoid the temptation in the first place. As a child, I remember my uncle Bob, who chose never to drink alcohol. When I asked him why, he said, "I am afraid I might become an alcoholic, and the one sure way to avoid that is to not start drinking in the first place." Many people today, knowing that cigarette smoking is highly addictive and unhealthy, pledge to avoid the addiction by never taking that first smoke.
If our positive reinforcement system promotes sinful behavior, why do we have such a system? Religious people might answer that God gave us such a system to test our faith, an idea as old as Adam and Eve. Other religious people might say we have the system because we can learn to avoid the negative reinforcers that are bad for us and seek out the happiness that positive reinforcers can produce.
Another advantage of the reinforcement systems comes from the motivation those systems provide. The reward system drives the brain to do beneficial things rather than reside as a passive recipient of whatever comes its way.
People tend to avoid religious practices or experiences that they find negatively reinforcing and seek to repeat those that are positively reinforcing. Thus, religion hooks everyone in the sense that the experiences compel a reaction. Atheists wiggle off the hook by rejecting spirituality. Believers find that the hook drags them into a positively reinforcing world. They may become hooked on religion.
Motivation is central to learning, and motivation is affected by personality type: people may fall into categories of those who “see the glass as half empty” and those who “see the glass as half full.” Each of us has an inherent predilection to be pessimistic or optimistic. The psychologist Martin Seligman pioneered the concept of learned optimism and learned pessimism. He argued that learning could adjust where a person is on this scale. In the case of learned pessimism, a person adds to a pessimistic mind set with every instance of bad life experiences if they are viewed as pervasive, personal, and permanent. Thus, a bad situation becomes much worse in the mind’s evaluation if it goes beyond the immediately obvious, is demeaning to one’s sense of confidence and self-worth, and will be long lasting. So, for example, if your religion teaches that you are fatally flawed by “original sin,” you are learning to be pessimistic and that there is nothing you can do to prevent more of the same in the future. Learned optimism is the attitude of mind that sin need not be typical of what you usually do, and that with God’s help you can prevent it from occurring again.
Religious implications have been explored in a study that compared fundamentalists (Orthodox Jews, Muslims, and Calvinists), moderates (Catholics, Conservative Jews, Lutherans, and Methodists), and liberals (Reform Jews and Unitarians).[12] Surveys reflected their degree of optimism vs. pessimism. The religious conservatives were the most optimistic, whereas the least optimistic were liberals. Variables such as income, sex, and education were irrelevant.
More optimistic people have more control over their emotions. Even a brain structure difference may account for this. Brain scans show that more optimistic people have larger volumes of the parahippocampus gyrus, a key structure in the limbic system of structures that controls emotions.[13]
Scripture calls for an optimistic outlook. The Christian Bible reads, “We know that for those who love God all things work together for good, for those who are called according to his purpose” (Romans 8:28). The Hindi teaching of Swami Vivekananda asserts that the essential features of Hinduism are its universality, its impersonality, its rationality, catholicity―and optimism.[14] The Qur’an states, “Hoping for good is also an act of worship of Allah.”[15] All these religions try to promote optimism in the form of hope.
Adolescence is a time of special responsivity to memories of religious experience. Church camps and mission trips can have life-long impact. Similar effects result from certain ceremonies, like confirmation in Christian churches or Jewish bar mitzvahs. In adolescents, brain scans indicate that the nucleus accumbens reward center is more sensitive to positive reinforcements.[16] This could have the effect of augmenting emotional responses to religious experience at the expense of reasoned examination of the implications and ramifications.
Repeatedly participating in positive religious experiences should strengthen religious memories, including all associated emotions. Self-control and discipline is at issue here, a fact long understood by ascetic religious groups such as monks and nuns.[17]  In the brain, one study using transcranial magnetic stimulation to disrupt function in the left, but not right, lateral prefrontal cortex, lessened self-control, in that immediate reward became more preferred over delayed rewards.[18]
It is one thing to forget, and quite another to remember falsely. In the context of religion, we may have false memories about our transgressions or those who transgressed against us. We may misremember scripture. In the face of temptation, we may forget our moral standards.
We should also consider a possible role for false memory in the creation of scripture, especially the oldest of scripture that was handed down from generation to generation by oral tradition. We have all perhaps seen this first hand in the parlor game where one person tells a story secretly to another, who then repeats the story privately to another, who in turn does likewise. After going through a chain of five to 10 people, for example, the story told by the last person in the chain is quite different from the original. Because most scripture originated and was repeated orally for centuries, this kind of corruption seems likely.
All religions expect the believers to remember the tenets of the faith. This is commonly manifest in the expectation to memorize significant portions of the scripture. Certain Islamic sects require children to memorize all 6,236 ayats (verses) of the Qur’an. The memory encoding stage involves a small group setting where the student memorizes half a page and recites it to the other students before reciting again to the teacher. The procedure repeats for the second half of the page and finally learners recite the whole page. The consolidation stage, involves five rehearsals of the previous memorized pages within 30 days so that the verses stay in the mind.[19]
"Memory athletes" use powerful mnemonic techniques, but these are not appropriate for the word-for-word memorization required of the Qur’an.[20] Here, the youngsters must use the tedious and inefficient rote method, where they repeat sections repeatedly and then move on to memorize the next section. They use chanting and rhythmic rocking movements to make the memorization easier.
Muslims and fundamentalist Christians regard their scripture as the literal "word of God," but Christians don’t require memorization of the entire Bible. The emphasis on memorizing scripture has two main problems. First, it reduces the necessity for thinking about the underlying truths and implications of scripture. Second, memorization keeps one from thinking about discrepancies in scripture, which are obvious upon analysis of both the Qur’an and the Bible. Fundamentalists often fail to recognize the possibility that they have confused worshiping scripture with worshiping God.
Memories shape who we have become. Long-term memory storage resides in the synaptic junctions among neurons. Repeated memory recall can cause changes in brain anatomy and chemistry that outlast the memory itself. Depending on experiences and on our health, new synapses may increase or decrease in number, and existing ones grow or shrivel. Thus memories of religious experience can make us more spiritual, even when we forget certain specific religious memories.
What we have become can predict our future. Our past religious experiences, good or bad, create yearnings, attitudes, beliefs, and hopes about religion that affect how we act and react to religious ideas and experiences in the future.



[1] Klemm, W. R., Goodson, R. A., and Allen, R. G. 1984. Steady‑state visual evoked responses in anesthetized monkeys. Brain Res. Bull. 13, 287‑292p
[2]Worsley, H. (2002). The impact of the inner-child on adult believing. Journal of Beliefs & Values, 23(2), 191-202. doi:10.1080/1361767022000010842
[3]Koenig, H. G., et al. (2015). Effects of religious vs. standard cognitive behavioral therapy on therapeutic alliance: A randomized clinical trial. Psychotherapy Research, 26(3), 365-376.
[4] Bartkowski J.P., Xu X., Levin M.L. (2008) Religion and child development: Evidence from the Early Childhood Longitudinal Study, Social Science Research 37(1), 8-36. http://dx.doi.org/10.1016/j.ssresearch.2007.02.001.
[5] Lipson, M. (1983). The influence of religious affiliation on children's memory for text information. JSTOR, 18(4), 448. http://dx.doi.org/10.2307/747379
[6] Julie Vidal, Julie, et al. (2012). Response inhibition in adults and teenagers: Spatiotemporal differences in the prefrontal cortex, Brain and Cognition, 79(1), 49-59.
[7] Slocum S.K. and Vollmer T.R. A. (2015).Comparison of positive and negative reinforcement for compliance to treat problem behavior maintained by escape. Journal of Applied Behavior Analysis, 48, 563-574.
[8] Lenroot, Rhoshel K. et al. (2007). Sexual dimorphism of rain developmental trajectories during childhood and adolescence. NeuroImage. 36(4), 1065-1073. doi.org/10.1016/j.neuroimage.2007.03.053.
[9] Crapps, R. W. (1986). An Introduction to Psychology of Religion. Macon, Georgia: Mercer University Press.
[10] Lewis, C. S. (1955).  Surprised by Joy. New York: Harcourt.
[11] Barweger, L (2013). Neuroscience and education: The importance of a Christian understanding  of human persons. ICCTE Journal. Retrieved from http://icctejournal.org/issues/v4i1/v4i1-neuroscience/   Complete ref.
[12] Sheena, Sethi, and Seligman, Martin E. P. (1993). Optimism and fundamentalism. Psychological Science 4(4), 256-259.
[13] Yanga, J., Wei, D., Wang, K., & Qui, J. (2013). Gray matter correlates of dispositional optimism: A voxel-based morphometry study. Neuroscience Letters, 553, 201-205.
[14] Aiyar, R. (1965). An introduction to Hinduism. Retrieved October 19, 2016, from http://www.staff.uni-giessen.de/~gk1415/hinduism.htm
[15] Ghayyur, T. (n.d.). 12 Sayings of the prophet to inspire optimism. http://www.soundvision.com/article/12-sayings-of-the-prophet-to-inspire-optimism. Retrieved October 19, 2016,
[16] Galvan, A., Hare, T. A., Parra, C. E., Penn, J., Voss, K., Glover, G., et al. (2006). Earlier development of the accumbens relative to orbitofrontal cortex might underlie risk-taking behavior in adolescents. Journal of Neuroscience, 26, 6885–6892.
[17] Rounding, K., Lee, A., Jacobson, J.A., & Ji, L.J.  (2012).  Religion replenishes self-control.  Psychological Science, 23(6), 635-642.
[18] Figner, Bernd, et al. (2010). Lateral prefrontal cortex and self-=control in intertemporal choice. Nature Neuroscience. 13, 538-539.
[19] Bhutto, Saifullah (2015). Traditional and modern methods used for memorization of Qur’an in Turkey. Ma’arif Research Journal, July-Dec. http://mrjpk.com/wp-content/uploads/Issue%2010/eng/10-Traditional%20and%20Modern%20Methods%20Used%20for.pdf. Retrieved Aug. 29, 2018.
[20] Saat, R.m., et al. (2011). Memorization activity and use of reinforcement in learning. Content analysis from neuroscience and Islamic perspectives. J. Applied Sciences 11(7), 1113-120.

Wednesday, November 27, 2019

Succeeding Without Brilliance


I recently got a note from a fan of this blog who was depressed because her IQ scores were not much above average. Her sadness magnified when she read a research paper from a group of 16 researchers at several prestigious universities who asserted that education after you are 20 years old doesn´t much improve your intelligence. My reader said, “That is devastating for me, as it makes it clearer that I´m pretty stuck in my "average" position. Do you think that this analysis is clearly conclusive? Or is there still some way to improve myself?”

She continued, “I dream of finishing my degree in Electronical Engineering and then going for Physics, but after seeing that analysis and lots of IQ charts for job positions and careers, I’m pretty disappointed.”

Before addressing her concerns, I need to summarize the paper that dismayed her. The report, published in the prestigious Proceedings of the National Academy of Sciences (PNSA) was based on what authors called General Cognitive Ability (GCA), which they defined as any IQ-like summary or principal component index of overall cognitive function. They admit and referenced some studies that have found that additional education increases intelligence, but their hypothesis was the opposite.

One thing the researchers did was conduct a basic meta-analysis of seven studies (10 datasets) with pre- and post-comparisons. The basic finding was that each additional year of education accounted for an average of 1.20 additional later-life IQ points.

My blog fan apparently missed the good news. That is easy to do, because the paper was one of the most poorly written and confusing research reports I have read over decades. This is what you might expect from anything written by 16 academics. What I think the report said about the meta-analysis was that each additional year of education accounted for an average of 1.20 additional later-life IQ points. You can see this as a glass half empty or half full. The half full view is that four years of formal post-high school education raises your IQ almost 5 points on average. Don’t bet the farm on this conclusion. These studies had an excessive amount of uncontrolled variables.

The PNAS paper did cite a study reporting that completing a university education led to a midlife gain of gains of 6–22.4 IQ points over adolescent cognitive ability compared with individuals who did not attend university. The students in that study were tested for IQ at age 15. That means that the average IQ of 100 could have jumped to 122, which is definitely adequate for most intellectually challenging careers. And this assumes just four years of ordinary college, without regard to major or rigor of intellectual challenge. Trust me, all college education is not equal.

These authors also conducted their own study and found little effect of education on IQ in an all-male, predominantly white, non-Hispanic sample at age 56-66. For example, averaging data across a large pool of subjects, they report that GCA accounted for 40% of GCA variance in late midlife and approximately 10% of variance in each of seven other cognitive domains. Averaging obscures the detection of individuals who could have had large GCA gains from education and life experience. Moreover, the kind of education and life experience must surely have varied widely and was not accounted for in the study. Even so, 60% of the variance in CGA did NOT depend on the test scores the men had taken when they were 20 years old. Don’t forget that 90% of late-life GCA variance was influenced by something other than formal education.

The IQ-like test they used was a military qualification test (AFQT), known to correlate well with established IQ tests. All their subjects, military veterans, took the test around age 20 and again about three decades later. Their data were interpreted to indicate that education does not make one much smarter. One result seemed especially clear: individuals with higher intellectual capacity tend to attain more education, achieve higher occupational status, and engage more in cognitive-intellectual activities.

There was an association of education, occupational complexity, and cognitive-intellectual activities with better later-life cognitive functioning, but these associations are not the cause of late-life ability. In other words, smart people are smarter when they are older because they were smarter to begin with. They became educated because they were already smart enough to seek it, not that education made them smart. The authors did concede that they were unable to definitively confirm their hypotheses regarding possible sensitive periods for brain development and the age of baseline testing. Such confirmation would require testing at multiple time points before the completion of education all within the same study.

One clear take-home message is that most intellectual gains occur before the age of 20. This is why elementary and secondary school education are crucial for creating optimal intelligence. As a professor for over 50 years, I am convinced that public schools today are not doing as much to make youngsters smarter as was the case in previous decades. That does not mean that further gains cannot be obtained after age 20. Education and intellectually challenging life experience do produce intelligence gains, just not as much as they do in youngsters.

The preference of researchers for averaging data obscures finding out what happens for a particular person. Is a person age 20 with low IQ more or less able to benefit from education than a person with a higher initial IQ? Or is it the other way around? Would the effect of education be different for women or minorities?

The kind of education and intellectual life challenge surely matter. For example, do we really expect the same mental benefit from four years of being a college physics major as an education major? Think also about still more benefit from a rigorous, emphasize rigorous, PhD program. Do we expect the same results from someone with little post-college training compared to a life-long learner?

IQ scores are affected by many things besides education that can affect how we interpret any effects of education. What about the age at which IQ is first tested? Brain development occurs throughout youth and extends past age 20. Obviously, IQ tests in elementary school are less valid than test results obtained after puberty.

Other variables affect IQ scores as well, particularly the mental state of the individual when the test was taken. Factors that will surely decrease scores, independently of actual cognitive ability, include sleep deficiency, emotional stress, and persistent mental distraction.

Consider especially stress. The persistent release of cortisol in chronic stress shrinks neuronal synapses and surely diminishes cognitive ability. The pool of veterans in this study must surely have varied widely in the amount of stress the men experienced during their military years. Some surely had combat-related PTSD, while others had non-stressful jobs.

One other thing: IQ tests not only measure how well you can figure things out, but only certain kinds of things, especially analogies. They also measure how fast you can solve a problem. Sometimes it doesn’t matter how long it takes to solve a problem. Einstein worked on special relativity for at least 10 years, despite claims of some others that it was a lightning-flash eureka moment.

What is my advice to my blog follower, and all those others, including me, with unimpressive IQs? First, do what you love that is helpful to you and others. But do not allow your reach to exceed your grasp. As the Army says, “Be all you can be.” The turtle sometimes beats the hare. But accept that the hare usually wins. Do not obsess or become stressed over your limitations, for that is counterproductive.

You should be happy and bring happiness to others. That should suffice. You don’t need the ability to invent relativity to be happy or make a meaningful contribution to others.

Source:
Kremen, William S. et al. (2019). Influence of young adult cognitive ability and additional education on later-life cognition. PNAS. 116(6), 2021-2026.




Friday, November 15, 2019

Flushing the Brain While You Sleep


I had written before about the breakthrough in studies of mice that showed lymphatic  flushing of brain tissue in mice while they slept. Now this phenomenon has been confirmed in humans. During human sleep, pulses of cerebrospinal fluid (CSF) flush throughout the brain. You can see a spectacular real-time video at this site: https://www.sciencealert.com/mesmerising-video-shows-waves-of-spinal-fluid-washing-over-the-brain-during-sleep.

Midline brain scan showing flushed area in red at one instant, pulsing at about 1-2 times/sec. From Fultz, 2019.

Interestingly, the flushing seems to include most of the brain, except the brainstem and the cerebellum. These CSF waves presumably flush out unnecessary proteins and other redundant debris. It is likely that the microtubule lymphatic-like system inside of brain tissue that opens during deep sleep is part of the CSF circulatory system. CSF is generated in specialized regions of the cerebral ventricles and ultimately drains back into the bloodstream.
Another research group simultaneously reported in the same issue of Science that cerebral blood flow diminishes by about 25% during slow-wave sleep, and apparently this facilitates an increase in the volume of CSF that can flow through the brain.

Another research group simultaneously reported in the same issue of Science that cerebral blood flow diminishes by about 25% during slow-wave sleep, and apparently this facilitates an increase in the volume of CSF that can flow through the brain.

The CSF pulsing is associated with slow-wave pulsing in the field potentials (as seen in EEGs, for example) generated by brain during the initial stages of sleep. The electrical waves and CSF pulses are coincident in a shared rhythm. The amount of slow-wave electrical activity diminishes in most elderly, and this may be a cause of dementia, which results from accumulated metabolic waste products. Sleep clinics could easily determine the amount of slow-wave sleep and thus perhaps detect early warning signs of impending dementia. Research on drugs and sleep habits that promote slow-wave EEGs might forestall and even treat dementia.

Sources:

Fultz, Nina E. et al. 2019. Coupled electrophysiological, hemodynamic, and cerebrospinal fluid oscillations in human sleep. Science. 366(6465), 628-631. doi: 10.1126/science.aax5440

Grub, Søren and Lauritzen, M. 2010. Deep sleep drives brain fluid oscillations. Science. 366(6465), 572-573. DOI: 10.1126/science.aaz5191

Sunday, November 11, 2018

Two New Discoveries to Explain Why Exercise Is Good for You


Have you noticed that so many elderly people seem frail, walk slowly, and seem to lack energy? If this applies to you, noticing it is unavoidable. These problems are preventable. For 25 years, I jogged at least a mile and a half three times a week. This was crucial for helping me stop smoking. I don’t know why, except that I could not smoke and jog at the same time. Also, the 15-30 minute recovery time reminded me just how bad the smoking had been for my health.

Why did I quit jogging? The jogging messed up my joints. So, I took up swimming, but since I sink like a lead mannequin, that is just too much work. So now, I joined a gym, where I use the elliptical, treadmill, and muscle-building machines. This environment helps because I have companions in my discomfort, and occasionally I get the satisfaction of comparing myself to the few “90-pound weaklings” that show up.

We have known for many years that exercise is good for you, especially as you get older. Known benefits of exercise include:

  • Relieve stress and promote a sense of well being. (Well, at least after the soreness wears off).
  • Improve heart and cardiovascular function. (If the damage is already done, don’t expect huge improvements).
  • Lose weight. (Pushing away from the table is the best exercise for this effect).
  • Strengthens bones. (Reduces loss of bone density in old age. But high-impact exercise may damage joints).
  • Lower blood sugar and help insulin work better.
  • Help quit smoking. (Ever try to smoke while jogging? Ha!).
  • Improve mood and resist depression. (Ever heard of “runner’s high? It comes from release of endogenous opiates).
  • Releases proteins and other chemicals that improve the structure and function of your brain. (Memory ability improves too).
  • Improve your sleep. (I mean, besides making you really tired. To reduce interference from soreness, take acetaminophen before bed time).\
  • Reduce your risk of some cancers, including colon, breast, uterine, and lung cancer.


What was not as well known until recently was the effect of exercise on the immune system. Recent research indicates that exercise in older age can prevent the immune system from declining and protect people against infections. A recent study followed 125 long-distance cyclists, and found that some of those in their 80s had the immune systems of 20-year olds. Maybe this is a reason exercise can help prevent cancer.

The key indicator was the level of T-cells in the blood. T cells, named after the thymus where they first appear, are a type of white blood cell that makes antibodies. As people age, the thymus gland, located in the neck, shrinks and T-cell activity resides mostly in bone marrow. The study of cyclists revealed that they were producing the same level of T-cells as 20-year olds, whereas a comparison group of inactive older adults were producing very few. Thus, it would seem that, though not tested in this study,   physically active seniors would also respond better to vaccines than sedentary people.

The other new discovery is the importance of exercise on brain white matter integrity. White matter electrically insulates nerve fibers, which has two effects: 1) speeds communication in neural networks and 2) reduces “cross talk” among adjacent fibers. The study compared people averaging 65 who were mentally normal and those who had mild cognitive impairment, which is a risk factor for later development of Alzheimer’s Disease. In both groups, investigators measured cardiovascular function with a standard measure of heart and respiratory fitness, the VO2 Max test. They also used brain scans to measure white matter integrity. Levels of physical activity were positively associated with white matter (WM) integrity and cognitive performance in normal adults and even in patients with mild cognitive impairment.

Given all this, how much more reason do you need to get off the couch and start moving? Besides, at the end of a good workout, it feels so good to quit.

*****
"Memory Medic's latest book is for seniors: "Improve Your Memory for a Healthy Brain. Memory Is the Canary in Your Brain's Coal Mine," available in inexpensive e-book format at https://www.smashwords.com/books/view/496252.  See also his recent books, "Memory Power 101" (Skyhorse), and "Mental Biology. The New Science of How the Brain and Mind Relate" (Prometheus).
*****
Sources:
Ding, Kan, et al. (2018).Cardiorespiratory fitness and white matter neuronal fiber integrity in mild cognitive impairment. Journal of Alzheimer's Disease, 61(2), 729-739.

Duggai, Niharika A. et al. (2018). Major features of immune senescence, including reduced thymic output, are ameliorated by high levels of physical activity in adulthood. Aging Cell. 8 March. 

https://medlineplus.gov/benefitsofexercise.html