Sunday, November 28, 2010

Nice review of "Better Grades. Less Effort."

I just saw a nice review was just posted at the Barnes and Noble site.
 
 
Bill

Friday, November 26, 2010

Learning In School. The "Problem with No-child Left Behind"

I see two main problems, one with the philosophy and one with the means of learning assessment.

As for philosophy, it sounds good, but like many social engineering efforts by the government, there are major unintended consequences that are too destructive. In this case, leaving no child behind has the effect of "no child pushed forward." In order to save kids who don't care about learning or whose parents don't care, we manipulate the whole system so that kids who are conscientious and who have talent are neglected. These kids don't pull down the schools' average scores on high-stakes testing, so they are left mostly to fend for themselves. The emphasis, which borders on compulsive, is on bringing up the bottom, so the school and teachers won't look so bad.

Worse yet is the unavoidable tendency to teach to the state standards and the test that is based on them. This not only engenders a "drill and kill" negative attitude among students, but many teachers just leave out most other enriching instruction that is not likely to get tested. For years, all of science was largely ignored in my state of Texas, because the high-stakes testing was restricted to English and math.

Also, the state standards are not infallible. In Texas, I know many educators who think the standards lack adequate rationale and coherence, especially across grade levels. States develop their standards by putting together a committee to write them. Such committees can be very opinionated, driven as much by ideology as by logic.

Then there is the assessment process of high-stakes testing. The President of the U.S. National Academy of Education, Professor Lorrie Shepard, recently argued that scores on these tests can be increased without any corresponding increase in learning or skills. This has been verified by use of other independent measures of the same content.

There is also the assumed necessity of using multiple-choice testing because so many schools and kids are involved. As an expert on memory, I can assure you that multiple-choice tests are the least reliable way to assess knowledge and understanding. More complex indicators of learning are needed, and this is recognized by the new, but very limited new program of "Race to the Top."

Shepard says if you really want to know whether education is being improved, especially in math and science, you have to evaluate such things as solving non-routine problems, to assess the reliability and meaning of evidence, apply knowledge in different contexts, and to communicate their learning effectively, both orally and in writing, In general, our schools don't do that.

Good teachers know how to assess learning without multiple-choice testing. They know how to structure student work requirements so that meaningful assessment is possible. In the old days, that is what teachers were expected to do. Today, they are expected to make sure the class scores high-enough on the state tests. A better approach, I submit, is to require students to create portfolios that reflect their ability to solve non-routine problems, evaluate evidence, and to apply and communicate their understanding. Then, these portfolios could be reviewed anonymously by an outside group, perhaps by educators in other schools, who in turn subject in reciprocal manner the portfolios of their own students to similar review.

Source:
Shepard, L. A. 2010. Next-generation assessments. Science. 330: 890.

Thursday, November 18, 2010

Neuroscience research working for you

I just attended the 40th annual meeting of the Society for Neuroscience in San Diego. There were over 31,000 scientists there, about 20,000 of whom presented research findings.Attendees come from all over the world. I an a Charter member of the Society and attended the first and most of the other annual meetings. It is hard for "outsiders" to appreciate just how much has changed in brain research over that time. The first meeting had less than 1,000 attendees. Now the meeting is so big that only a handful of U.S. cities can host such a large meeting.

There were many papers on memory presented. Most, however, were focused on how the brain achieves memory, and a lot of that has no immediate practical application for everyday life. I keep an eye out for such papers and report them in this blog when I find it.

One paper confirmed what I already knew about teaching "old dogs new tricks."  It showed that learning of a series of items was impaired in Seniors compared to younger people, but the deficiency was overcome if the experimenters just increased the interval between presentation of items. In other words, you CAN teach old dogs new tricks, it just takes longer.

I was really excited to see that I am on the right track on my new book, due out from Springer next Spring. The book is titled "Atoms of Mind. The 'Ghost in the Machine' Materializes." A few scientists are starting to do  the kind of research I advocate in the book for the study of consciousness. While at the meeting, I got a new idea nobody has considered yet. I'll tell people about it in the book, which I am mailing off to the publisher in a week or so..

I presented a paper on why people dream. A commonly accepted idea is that we dream to consolidate memories of the preceding day's events  It is true that memory consolidation does occur in sleep, both dream and non-dream sleep. But that is not the CAUSE of either dreaming or non-dreaming sleep. It is the consequence.

The simple answer is that we dream because the brain becomes activated in what is called REM sleep. Activated brains want to think, and thinking during sleep is expressed as dreams. So the real question I addressed is why do we have REM sleep. It's a long story, but the short answer is that REM helps to re-boot a sleeping brain so that we can become awake and conscious again. My presentation was well received. I had 50 copies of handouts, and they were scarfed up in the first 30 minutes of my poster session. Lots of people left their e-mail address so I could mail them copies of the poster. Over 100 people came by the poster. And they weren't window shopping. They stayed, read it all, and discussed it with me during the time when I was attending the poster. Nobody could punch any holes in the theory. I think I have the best explanation anybody has every presented.

It has been a stimulating four days. I will need some time to unwind.

Thursday, November 11, 2010

B Vitamins, Brain Shrinkage, and Memory

I have discussed nutritional effects on memory and warned readers that many claims are just so much undocumented hype. Here is a study, apparently very well done by a group at Oxford University, that shows supplementing diet with B vitamins can help prevent mental decline in the elderly.

As people age, the brain tends to atrophy, even in healthy people, and this of course can contribute to mental decline and senility. A risk factor for brain atrophy in the elderly is homocysteine, an amino acid best known as being a risk factor for coronary heart disease, stroke and peripheral vascular disease. B vitamins (folic acid, B6 and B12) reduce the blood level of homocysteine. In the Oxford study, 271 people over 70 years old with mild cognitive impairment were given a mixture of the B vitamins daily for two years. Brain size changes were monitored with brain scans.

During the test period, brains shrunk 1.08% in the non-supplemented controls and 0.76% in those that got the B vitamins. There were correlated changes in blood homocysteine levels and performance on mental tests.  Daily doses used were folic acid: 0.8 mg; B6: 20 mg; and B12: 0.5 mg.(I just checked my own brand-name one-a-day multi-vitamin pills, and they have a lot less of B6 and B12.)

If brains shrink at this rate (actually shrinkage probably accelerates over time), the difference by age 90, for example, would be substantial. Shrinkage would be even greater if there were other factors such as large alcohol consumption or Alzheimer's disease. One could also expect B vitamins to provide some benefit for the cardiovascular system, though this was not evaluated in this study.

Source:

Smith, A. D. et al. 2010. Homocystein-lowering by B vitamins slows the rate of accelerated brain atrophy in mild cognitive impairment: a randomized controlled trial. PLoS ONE. doi/10.1371/journal.pone.0012244

Saturday, September 25, 2010

Better Grades. Less Effort


What can be more important to a student than to have good memory skills? The same is true for working professionals in information-dense specialties (like law, medicine, science, engineering, etc.). Memory ability helps workers master their field and become more competent -- and more likely to be successful.

I have just released a short new e-book, Better Grades, Less Effort. The book explains the memory tips and tricks I used to become valedictorian, an Honors student in three universities (including graduating with a D.V.M. degree), and to secure a PhD in two-and-a-half years. I also share what I have learned about student learning over 47 years as a professor.

The ideas in the book are directed to students in high school or college. Parents are urged to explain these ideas to their elementary-school children.  My experience with students leads me to conclude that poor memory is what holds most students back from superior achievement.  I claim that the ideas in this book can change a student’s future, as indeed has been validated in my own life.

The other thing I have learned as a Professor is that most students think they know more about how to learn than they really do. In elementary and secondary schools, the emphasis of teaching is on WHAT to learn, not HOW to learn. By the time students get to college, professors mistakenly assume they already know how to learn.

My relevant experience also includes being a researcher and teacher of neuroscience, an interdisciplinary field focused on how the brain works, including how it learns and remembers. I have actually conducted memory research, on lab rats and college sophomores. The principles are the same. Sometimes, the rats do better than the people. Unlike lab rats, which are really pretty good at learning and remembering, humans have a huge repertoire of behaviors and experiences that interfere with remembering. Many of the tips explain what I mean.

Better Grades explores 20 core  ideas about improving memory in a few pages for each idea. The book’s structure is itself an example of some core ideas. For example, ideas are grouped according to common category: Attitudes and Approach, Classroom and Study Environment, Memory Principles and Processes, plus a General  Tips section with three ideas that don’t fit into the above categories. At the end of each group, there is a “tying it all together” section that uses mental-image mnemonics to help readers remember what they just read in the preceding section. At the end of the book, a similar approach helps the reader remember the whole book.

I claim that If readers do what this book says, they will be able to memorize:

  1. all the key ideas of this book,
  2. any list up to 100 items,
  3. dates and numbers,
  4. the essence of what  is on every page — by page number — of any short book,
  5. a class presentation or speech without notes,
plus, as promised, they will get better grades with less effort.

The book is priced at $2.49 so that every student can afford it. My whole point in creating the book is to help as many people as possible. Access to information and a free chapter can be found at http://thankyoubrain.com. All e-reader formats are supported, including pdf for reading on computers.

Tuesday, September 14, 2010

Monday, September 13, 2010

New Treatments for Post-traumatic Stress

A new therapeutic approach is in sight for treatment of traumatic memories, including memories that cause PTSD. Two lines of memory research have converged to produce a treatment, and sometimes even a cure, for the most serious need to forget, PTSD. This may not be generally known or accepted, but at least two research groups have shown there is a blood pressure drug, propranolol, that helps us to forget overwhelmingly stressful memories and thus reduces the stress that goes with those memories. The latest treatment being investigated by some researchers is based on using a common blood pressure drug, propranolol, which has a side effect of blocking the re-consolidation of emotions associated with old memories when those memories are recalled.

One reason it is possible to forget or at least edit memories is that when even well-formed memories are recalled, they are put back on the scratch pad of working memory where they are accessible to “editing” and re-consolidation. As I explained in a  previous blog column, each time a memory is retrieved, it can get changed and re-stored in a different way.

While memories reside on the scratch pad of working memory, either for the first time or during any recall episode, they can be changed by drugs. Also relevant here is that memory consolidation is greatly influenced by the impact of the experience, which is magnified by strong emotion and the hormones such emotions release. During re-consolidation, under conditions of proper talk therapy, the emotional impact need not duplicate the original and a more benign version will be stored in memory.

The rationale for testing propranolol was developed in the seminal work by Roger Pitman and colleagues. They noted earlier studies showing that adrenalin (epinephrine), either injected or released naturally under stressful conditions, strengthens memory formation and fear conditioning. Adrenalin helps you to remember the bad event and hopefully you can avoid facing that threat again by being alert and prudent. Adrenaline acts on a class of molecular receptors called beta-adrenergic receptors. Certain drugs, among them propranolol, block beta receptors and thus might theoretically disrupt fear-induced memories. Several groups have confirmed that propranolol does impair fear-conditioned memory in both animals and humans.

Pitman’s group sought to extend this notion to PTSD in a pilot study of 41 patients. They conducted a double-blind, placebo-controlled study in which a single 40 mg oral dose of propranolol was given as soon as possible (within 6 hours) after a traumatic event experienced by patients who had been rushed to a hospital emergency room. Patients then continued the medication four times a day for 10 days followed by a 9 days when the dose was progressively reduced to zero.

One and three months later, patients returned for psychological testing aimed at measuring PTSD. At one month post trauma, the number of patients with PTSD in the propranolol group was almost half that of placebo controls. Not tested was the possibility that a larger dose, especially if given early or prior to the unpleasant experience, might be even more effective, since there probably is a narrow window of opportunity for the drug to be beneficial in impairing the consolidation of bad memories.

A similar result was obtained in a later study by Guillaume Vaiva and colleagues. Their hospital emergency room patients were given propranolol or a placebo 2-20 hours after experiencing an auto accident or physical assault. The patients tested were also selected for having abnormally fast heart rates, because propranolol is a common therapeutic for that condition. Propranolol was given in a dose of 40 mg three times daily for seven days, followed by gradual reduction to zero over 8-12 days.

Under the common situation where emotional trauma has already been consolidated, the obvious treatment approach for PTSD might be to have patients recall the traumatic event later while under the influence of propranolol. The idea is that during recall, the memory and its associated emotion have to be reconsolidated, and this is disrupted by the drug. Indeed, this idea is being hailed in some quarters as a possible major breakthrough in treatment of PTSD. Many positive results are being reported by physicians, and the Army is considering using this approach for combat-related PTSD. The National Institute of Mental Health is now recruiting patients for a Phase IV Clinical trial.

One obvious conclusion is that propranol might be a good PTSD preventive drug if given before an anticipated traumatic event. For example, I wonder if D.O.D. psychiatrists have thought about giving propranolol to combat troops just before they engage in battle.

Another issue that nobody seems to consider is the possibility that people on this kind of blood pressure medication might be suffering impairments of emotional memories that they don't want to lose. Does this drug cause a general dulling of emotions? Could it magnify the failing memories of the elderly?


Copyright 2010, W. R. Klemm. Dr. Bill Klemm is a Professor of Neuroscience at Texas A&M University. Visit his book site and blog at ThankYouBrain.com for more help on improving memory.

Tuesday, September 07, 2010

Zombies Learn Too, But Not Well

I recently had a scholarly paper on free-will research published in a cognitive psychology journal. This experience has caused me to think about the role of free-will in learning and memory. Though it might seem like a stretch, how one approaches learning affects how well it is done. If you learn subconsciously, as in  being conditioned like Pavlov's dogs or trained seals, the learning is primitive and limited because it is hidden from consciousness. I call this zombie learning (anybody who has lectured to students has seen this happening throughout the room). On the other hand, when one consciously and freely wills to learn, he becomes engaged as an active learner. Such learning, being mediated in the consciousness, is available for refinement, expansion, application, and integration into other learning, past and future.

Thursday, August 19, 2010

Traumatic Memories, Part 1

Most of the time, most of us wish we could remember things better. But some of the time all of us have things we wish we could forget. Traumas, emotional upset, grief — all can be more than we can wish to bear.
     When anxiety becomes too intense and persistent, the level of stress becomes de-bilitating. There are many negative effects on the adrenal gland and its production of hormones that are designed to cope with stress. Beyond that, the brain is also affected. These effects are the hallmark of what is commonly called “Post-traumatic Stress Syndrome” (PTSD), which seems to be a common and growing problem with American soldiers returning from Iraq and Afghanistan. While older people are in the wrong age bracket to have this problem, they are very likely to know about PTSD in soldiers and may even have children or grandchildren who have PTSD.
     You don't have to be a combat soldier to develop anxiety disorders such as PTSD. Everyone has probably had some kind of traumatic experience that caused a serious emotional trauma. Such experiences are always associated with a host of cues, many subconscious, that are part of the original learned traumatic experience. The learned association may be remembered at some unconscious level long after the conscious memory is lost.
      Sensory cues, even if not recognized consciously, can trigger recall of disturbing memories or even just the negative emotions that went with the original bad event. Sometimes this is the basis for so-called “anxiety attacks,” which seem to come out of nowhere.
      Anxiety disorders are among the most common mental health problems and are often treated with so-called extinction therapies. That is, therapy is geared toward unlearning (extinguishing) our fears by deliberately re-living the disturbing event under safe conditions and thereby learning we can cope.      
Modern psychotherapy for phobias, anxiety, and PTSD often involves recalling the original bad event under reassuring conditions. But this has to be done with conscious re-assessment and realization that the original negative emotions and fear are no longer applicable because the re-living is a simulation in a safe environment. One creates a new learning substitute for the original emotional trauma.
      The re-living must include dealing with the negative emotions in the light of reason and new emotional experience. Therapy requires critical thinking about thoughts and feelings, especially those that are unhelpful and unrealistic. The patient is gently led to face memories anew and to learn new ways of thinking and behaving. This re-creation of the bad event allows us to extinguish memory of the original bad situation and its negative emotions.
      I recently got an up-date in this area of research at a seminar by Gregory Quick from the Department of Psychiatry at the University of Puerto Rico. As Pavlov showed, memory extinction is a basic phenomenon even in simple animals. If you repeatedly ring a bell and then stress a rat, it soon learns to become distressed the next time it hears that bell, even after you stop the stress. In the lab, this is manifested by the rat showing freeze behavior. But, if you repeat the bell enough times without the stress, the conditioned response (CR) (freeze behavior) eventually becomes extinguished.
     At first, scientists thought that extinction erases the memory of the CR. But extinction really creates a new memory that competes with memory of the original CR. Both memories co-exist. Over time the extinction memory may be lost, and the CR can return. The implication is that, just as ordinary learning needs rehearsal, so does extinction learning.
     Therapy for emotional trauma and PTSD might be more effective if therapy were approached like a conventional learning experience whose memory is affected in all the usual ways. Recall what was said about extinction being a case of new learning. Re-learning of an extinguished response occurs much more readily than it does for an initial extinction learning. This is an example of priming. It’s like re-learning a foreign language. It goes easier the second time and the memory might be even more dependable.
      Since memory of an emotional CR learning experience and its extinction can co-exist, these two memories compete for which one is strong enough to survive long-term. Sadly, the CR memory is often stronger. Cues are extremely important to both forming and retrieving all kinds of memory. It seems likely there are many more explicit cues for CR memories than for extinction memories. Therapy should be aimed at enriching the number and variety of cues associated with extinction learning. Rehearsal is likewise important. So far, nobody seems to have given that much thought.
     There is another aspect to emotional learning: learning to learn. If you have multiple anxieties, they may generalize and "spread" to facilitate learning new anxieties. The corollary would be that learning how to promote extinction could also generalize and thus increasing the general ability to cope with emotional trauma. Obviously, for one's brain to learn how to do that, one would need to begin with a single relatively easy extinction learning task.
    
     Dr. Bill Klemm is a Professor of Neuroscience at Texas A&M University. Visit his book site and blog at ThankYouBrain.com for more help on improving learning and memory. Copyright 2010, W. R. Klemm

Saturday, July 31, 2010

Music Training Helps Learning & Memory

Music training is good for the brain. Nina Kraus, a prominent brain researcher at Northwestern University, says that "music training leads to changes throughout the auditory system that prime musicians for listening challenges beyond music processing." The research in her laboratory and that from other labs suggests music training does for brain what exercise does for body fitness. She says "music is a resource that tones the brain for auditory fitness."

Musicians are commonly studied models for neural plasticity, which refers to the ability of learning experiences to change the brain chemically and physically. Musicians have more brain grey matter volume in areas that are important for playing an instrument and in the auditory cortex, which processes all kinds of sound. Of course, the effects of music training are most robust for processing of music. But benefit transfers to speech, language, emotion, and general auditory processing.

In general, auditory learning requires formation of efficient sound-to-meaning relation-ships, which in turn require attending to sensory details (fine-grained properties of sound such as pitch, timing and timbre), but also thinking skills related to integrating sensory input and operating on it in working memory.

Music training confers ability to assess the relevance and predictability of information-bearing elements in an auditory signal. So, even in non-musical contexts, such as listen-ing to a speech, lecture, or sound track in a movie for example, musicians should learn and remember more of the content than non-musicians. Musicians also have an advan-tage when it comes to learning the sounds of a new language.

Music training imposes a high working-memory load. That can be a good thing, in that it helps you expand your working memory capacity, and thus reduces the impairing effects on memory of working memory overload. Increasing working memory capacity also improves the ability to think, as manifest in IQ scores. Since musicians usually have greater working memory capacity, it doesn’t mean they are smarter than anybody else. But it probably does mean they are smarter than they would be if they were not musicians.

Music training also helps improve certain memory capabilities outside of music. For example, musicians show improvements in auditory verbal memory and auditory attention, but not in visual memory or visual attention. This brings up the matter of learning styles: auditory, visual, or kinesthetic learning. Most people are visual learners, but to the best possible learners they need to develop all three styles. Music training should help their auditory learning style, especially under conditions where the sounds to be learned are embedded in conflicting sound stimuli, such as noisy rooms or learning a new language.

All fine and good, but how does this apply to the masses who are not musicians? Would listening to a lot of music help the brain? I doubt it, for listening does not make rigorous task demands on the brain. Would music training for non-musicians help the brain? Maybe, especially if the training occurred at a young age when the brain is ma-turing.

One study of children showed that fifteen months of intense music training induced structural changes in the primary auditory and primary motor areas. These structural changes were associated with improved auditory and motor skills, respectively. Other studies show children who are musically trained, compared with non-trained children, have a better vocabulary in their native language and a greater reading ability.  Pre-sumably, they would be better at learning other languages.

When and how much music training should be provided to children? Formal studies suggest that greatest benefit occurs if training begins before age 7. The benefits also cor-relate with the amount of music practice. However, much remains to be learned about effects of age and duration and nature of the music training.

Nina argues for more and better music education in the early grades of schools. She be-lieves music training may benefit academic achievement by improving learning skills and listening ability, especially in challenging listening environments, which are all too common in classrooms which are usually very noisy, despite research proving that classroom noise impairs learning. Noise not only creates problems of discerning salient sounds embedded in the over-all noise, but also creates a major distraction that impairs focused attention, information registration and memory consolidation.

I have summarized earlier research showing IQ in children improves when they are taught to have larger working memory capacity. Since working memory is apparently increased by music training, and music training also apparently enhances auditory learning, it seems like a no-brainer to suggest that more music training needs to occur in elementary school.

Source:
Kraus, N. and Chandrasekaran, B. 2010. Music training for the development of auditory skills. Nature Reviews. Neuroscience. 11: 500-505.

Friday, June 25, 2010

Multi-tasking and Memory, One More Time

I have talked about the problems of multi-tasking before. But this trend among youg people is so pernicious and damaging, I just have to bring it up again.

A whole new generation of multi-taskers is upon us. These young people know how to use cell phones, text messages, the Web, video games, IPods, and assorted other electronic gizmos, often at the same time. Sometimes, driving a car is thrown in for good measure (until an accident occurs).

I work with secondary school teachers, and most of them are in awe of these kids. I have seen teachers brag about how talented their own kids must be because they are such impressive multi-taskers. Increasingly, however, teachers come to realize that multi-tasking intereferes with learning. Some teachers are particularly upset with cell phones, which they try to ban, with little success. Talk about trying to take candy from a baby! In the old days, we kids tried to hide reading of comic books during class. Today, the game is to hide text messaging on cell phones. Ah, such is progress.

Multi-tasking is certainly a talent, but one that exacts a high price on learning. Formal brain research has shown that the brain can only do one thing at a time. Multi-tasking is accomplished much in the manner of "multiplexing," an engineering term denoting doing one thing for an instant, then another, and another, and finally returning to the next step of the first task. All this switching is distracting and interferes with memory formation and what memory reseasrchers call "consolidation" into lasting memory.

Memory consolidation is often prevented when one event follows too soon after an initial learning event. There is a whole theory about this, called the Interference Theory of Learning. Memory of initial learning events can be blocked if you try to learn two things at once. In fact, learning may be disrupted for both things.

In a recent test of this phenomenon, a group of 29 people (17 to 30 years of age) was trained to discriminate two sound pips that differed in length by a fraction of a second. In one group of subjects, the training occurred consecutively, which ordinarily produces some inefficiency with learning because the second task interferes with remembering the first. Moreover, results from another group of subjects revealed that when practice on the two tasks was interleaved in multi-task fashion, there was no learning on either condition.

Another recent study should get your attention: a group of study participants, divided into those that were heavy multi-taskers and those that multi-tasked only infrequently. All participants were probably at the higher end of general mental capabilities, given that they were Stanford college students. Each participant was tested in a series of thinking tests to check for any difference in the way the two types of people processed information and disciplined their attentiveness. Heavy multi-taskers were less able to sustain focus in the presence of distractions. The heavy multi-taskers performed worse even though their experience and presumed skill at multi-tasking should have made them more effective at these tasks. The heavy multi-taskers believed they were good at multi-tasking, when in fact they were bad at it.

Nor is intelligent thought likely to benefit from multi-tasking. Multi-tasking bombards working memory with scrambled and unfocused information and probably keeps the brain from learning how to optimize focus and orderly sequence thoughts. Several studies show that intelligence correlates with working memory capacity, which under the best of circumstances is limited. Working memory is the platform on which you think.Over-loading this small-capacity thinking platform just makes it harder to think straight.

So, now tell me again why multi-tasking is a good ability. While you are at it, try to convince me that it has no deleterious effect on ability to focus, sustain attention, and think.

Sources:

Banai, K. et al. 2010. Learning two things at once: differential constraints on the acquisition and consolidation of perceptual learning. Neuroscience. 165: 436-444.

Ophir, E., Nass, C. and Wagner, A. D. 2009. Cognitive control in media multitaskers. Proceedings of the National Academy of Science. Aug. 24. doi: 10.1073/pnas0903620106

Friday, May 28, 2010

Magnesium: a mineral you need and may lack

The only time I ever thought about magnesium,  before I became a scientist, was the summer I swept magnesium shavings off the floor at the Kaiser helicopter-engine factory. When I went to college, I learned that magnesium was an essential mineral in human and animal bodies. As a veterinary medical student, I learned that a magnesium deficiency caused "grass tetany" in cattle that ate lush, heavily fertilized grass growing especially in soils high in potassium or aluminum; these conditions reduce availability of magnesium.

Recently, a MIT scientist, Inna Slutsky reported a five year study showing that magnesium improved learning abilities, working memory and both short- and long-term memory in rats. The improvements were produced in both young and old rats. They fed rats a synthetic magnesium supplement, magnesium-L-threonate (MgT), which improved the ability of magnesium to get across the blood-brain barrier and into nerve cells.

How magnesium benefits brain function is probably related to the fact that magnesium is a cofactor for enzymes that convert adenosine triphosphate (ATP) to adenosine pyrophosphoric acid (ADP), with the subsequent release of energy. The brain is a real energy hog.

How much MgT would humans need to take is not known, but presumably somebody is working on that. The recommended daily amount of magnesium is 400 milligrams for men and 310 milligrams for women. It is estimated that only 32% of Americans get this amount in their diet. Primary food sources are green veggies, fruits, and certain nuts.  Traditional nutritional supplements are not a solution. The researchers found that the magnesium in common dietary supplements does not readily enter the brain.

A commercial product, when it becomes available, may not have been tested for safety (nutritional supplements are not government regulated), On the other hand, healthy kidneys are pretty good at getting rid of excess blood magnesium. The possibility of excess magnesium in the brain from use of MgT has not been investigated.

Source:
Slutsky, I. et al. 2009. Enhancement of learning and  memory by elevating brain magnesium. Neuron. 65 (2): 165-177.

Copyright, 2010, W.  R. Klemm

Monday, May 10, 2010

Can Exercise Help Kids Do Better in School?

Even when I was a kid, people said that being physically active could help you perform better in school. But this was mostly anecdotal, with very little research evidence. Now there is some evidence.

Charles Hillman and colleagues at the University of Illinois recently reported a study on the eff
ects of exercise on cognitive function of 20 preadolescent children aged 9 to 10. They administered some stimulus discrimination tests and academic tests for reading, spelling and math. On one day, students were tested following a 20-minute resting period; on another day, students walked on a treadmill before testing. The exercise consisted of 20 min of treadmill exercise at 60% of estimated maximum heart rate. Mental function was then tested once heart rate returned to within 10% of pre-exercise levels. Results indicated improved performance on the tests following aerobic exercise relative to the resting session. Recordings of brain responses to stimuli suggested that the difference was attributable to improved attentiveness after exercise.

Note that this is just from a single aerobic exercise experience. How can that be beneficial? The most obvious explanation is that exercise generates more blood supply to the brain, but I don't know that this has been documented with MRI studies, for example. Actually, what is known is that exercise diverts blood to the muscles. The generally accepted view is that the body tightly regulates blood flow to the brain and that the brain always gets what it needs. Another possibility is that exercise relieves anxiety and stress, which are known to disrupt attentiveness and learning. Maybe the repetitive discipline of exercises like treadmill walking help entrain the brain into a more attentive mode. We need a study that compares tradmill walking with a different kind of exercise regimen (like a vigorous and competitive basketball game, for example).

As for what goes on in a typical school recess, I doubt that such activities as shooting marbles, gossiping, or whatever else goes on these days with kids at recess, really helps school work. Gym class might be another matter, but unfortunately many schools do not provide a meaningful gym class. Some of the authors' suggestions don't
seem to be supported by this particular research. For example, they advocate:

• scheduling outdoor recess as a part of each school day (recess does not typically provide aerobic levels of exercise)

• offering formal physical education 150 minutes per week at the elementary level, 225 minutes at the secondary level (again, the beneficial effects likely come from aerobic
levels of exercise, not just any exercise)

• encouraging classroom teachers to integrate physical activity into learning (this almost certainly will not be at aerobic levels of exercise.)

There is the also the issue of a continuing aerobic exercise program, which presumably could produce long-lasting beneficial effects in young children. My own prejudice is that schools and parents ought to get serious about requiring an aerobic exercise program for kids. It should not only improve the quality of school work but also help combat the epidemic of obesity and diabetes. One caveat: running to achieve aerobic levels of exercise may not be advisable in children. My own exp
erience with jogging, for example, might have been great for my heart and brain, but I now have two artificial kness to show for it.

If exercise is so good for academic performance, why do varsity athletes generally make poorer grades than their classmates? Well, there are many other factors, of course. One prevailing attitude among athletes is that academics are less important to them than their sport. Their peers idolize athletic stars. Students who make all As are not considered heroes; they are considered nerds or otherwise abnormal. Athletes devote their time and energy to their sport, not school work.

Reference:

Hillman, C. H., et al. 2009. The effect of acute treadmill walking on cognitive control and academic achievement in preadolescent children. Neuroscience. 31;159(3):1044-54.


Monday, April 19, 2010

The Multi-tasking Scatterbrain

Nobody should be surprised that people who multi-task a lot are easily distracted. It could well be that they multi-task a lot because they are so distractable and less able to focus.

A recent rigorous study of this matter evaluated a group of study participants, divided into those that were heavy multi-taskers and those that multi-tasked only infrequently. All participants were probably at the higher end of general mental capabilities, given that they were Stanford college students. Each participant was tested in a series of thinking tests to check for any difference in the way the two types of people processed information and disciplined their attentiveness.
  
Heavy multi-taskers were less able to sustain focus in the presence of distractions. The researchers concluded that light multi-taskers "find it easier to attentionally focus on a single task in the face of distractions."

The study did not directly examine ability to memorize, but there surely must be a significant difference, given that memory formation is enhanced by sustained attentiveness and focus. There may be some undiscovered benefits of multi-tasking, but memorizing cannot be one of them.

Nor is intelligent thought likely to benefit from multi-tasking. Several studies that I have summarized elsewhere show that intelligence correlates with working memory capacity, which under the best of circumstances is limited and easily over-loaded by multiple simultaneous informational input.

The study did not test whether distractibility is a cause or a consequence of multi-tasking behavior. But the data clearly support the notion that people whose work or study requires concentration should not multi-task.
There is also the potential problem that frequent multi-tasking could be teaching the brain to become more distractible.

Source:

Ophir, E., Nass,  C., and Wagner, A. D. 2009. Cognitive control in media multitaskers. Proceedings National Academy of Science. 106 (37): 15583-15587. doi/10.1073/pnas.0903620106

Sunday, April 18, 2010

Vitamin D: the wonder vitamin

Everybody knows that vitamin D is good for healthy bones. That is why they fortify milk with it. You may not know it is good for certain skin conditions, such is the one I have that appears every Winter when I don’t get enough sunlight, even though I live in Texas. Taking 2,000 IU vitamin D3 daily has stopped this problem. I read also that vitamin D stimulates the immune system. I am now surprised to learn it might be helpful for memory.

A research group in the United Kingdom, recognizing that many people are vitamin D deficient there because they don’t get much sunlight to help the skin generate vitamin D, pursued the question of why there are molecular receptors for vitamin D in the brain. What is that all about?

Some previous studies by other groups had shown vitamin D has protective effects on the brain and enhances its activity. Other studies had shown that low serum levels of the 25 (OH) form of vitamin D were associated with poor cognitive test performance among patients with mild Alzheimer disease, and a study of older adults revealed a positive correlation between 25(OH) D blood levels and scores on a mental function test.

This British study looked at a large population (3,133) of middle-aged and older men to evaluate the association between vitamin D levels and cognition. Specifically, the investigators tested blood levels of serum 25-hydroxyvitamin D in non-institutionalized European men, aged 40–79 years, and compared those levels with performance on three mental-function tests, one of which was a specific test of memory. High blood levels of vitamin D were associated with better performance on a test for analyzing complex visual images and a recognition memory test.

Studies like this are exceedingly complex, because there are many hard-to-control variables (the paper had more than 21 authors). Not surprisingly, depression, physical activity, physical performance, and smoking were all consistently associated with both cognitive test scores and 25(OH) D concentrations. Some mental-test scores, together with 25(OH)D levels, were additionally associated with drinking one or more alcoholic drink per week. Also, as expected, 25(OH) D levels varied markedly by season, peaking in the summer and reaching bottom in the winter.

After additional adjustments for age, education level, depression, basal metabolism, physical activity, physical performance, smoking, alcohol consumption, season, higher 25(OH) D concentrations were found to be associated more specifically with psychomotor speed and visual scanning.

Vitamin D exists in two common forms; vitamin D2 and D3. The form mainly produced in the skin and derived from natural dietary sources is vitamin D3, whereas the primary source of vitamin D2 is multivitamin preparations and some fortified foods. There have been conflicting reports as to whether vitamin D2 and vitamin D3 are equally effective at maintaining 25(OH) D levels,

Nobody knows why vitamin D affects brain function, but the existence of specific molecular receptors inside the nucleus of neurons cannot be dismissed. Possibilities include direct effects on promoting synthesis of the alertness-producing neurotransmitter, acetylcholine, or more indirect effects on intracellular calcium (calcium is a signaling molecule  in nerve cells). Other possible ways vitamin D might help brain function include its ability to stimulate synthesis of nerve growth factor.  Vitamin D is neuroprotective against stroke and, by its ability to attenuate neurotoxic insults, could have a major impact in preventing neurodegenerative diseases.  Vitamin D has the potential to increase glutathione which helps with detoxification and protection against free radical stress.

It is still an open question whether vitamin D helps memory. But I will keep taking my vitamin D3 to help my skin condition. Any benefit to my memory will be a much-appreciated bonus.


Source:

Lee, David M. et al. 2009. Association between 25-hydroxyvitamin D levels and cognitive performance in middle-aged and older European men. J. Neurol. Neurosurg. Psychiatry. 80:22-729. Doi: 10.1136/jnnp.2008.165720.

Friday, April 02, 2010

Resveratrol: the red wine magic chemical

I try not to get too excited about memory benefits of supplements. Certainly, I only have any level of faith in formal scientific studies that are well controlled and peer reviewed. I now think that resveratrol may be one of the few supplements that could have beneficial effects on brain function.

You no doubt have heard about the French red-wine drinkers, who are more healthy than they ought to be, given that they drink too much, exercise too little, and eat too much fat (as in goose liver and cheese). In trying to figure out how this can be, scientists have homed in on a major anti-inflammatory chemical in red wine, known as resveratrol. At this writing, over 2,000 scientific papers have been published. Don't worry, I am only going to tell you about a few. Most of the protective biological actions associated with resveratrol have been associated with its intrinsic radical scavenger properties and the protective effects that it confers on the heart.

Most of this research focuses on the compound's beneficial effects on heart and blood vessels and diabetes. The compound targets multiple enzymes in multiple organs. What I am summarizing here is recent research that suggests resveratrol might be beneficial for thinking ability in general and memory in particular.

A diabetes research group in Brazil recently reported a beneficial effect of resveratrol on diabetic rats. An earlier study by another group showed that resveratrol improved glucose metabolism and promoted longevity in diabetic mice. Other research groups had reported neuroprotective effects for resveratrol. The Brazil group focused on brain damage produced by diabetes. They induced diabetes in a group of rats, observing that this impaired their ability to memorize. The cause, as indicated by other studies, is that diabetes lowers the level of a major brain neurotransmitter that promotes alertness, attentiveness, and general cognitive function, acetylcholine. As an aside, the major treatment for Alzheimer's disease is Aricept, which enhances acetylcoline function. The Brazil group found that resveratrol suppressed activity of the enzyme that destroys acetylcholine, thus tending to restore more normal acetylcholine function. Resveratrol (in a modest rat dose of 10 and 20 mg/kg per day for 30 days) prevented the impairment of memory induced by diabetes.

Added to this finding about the brain enzyme, there are other reasons to think the anti-oxidant properties of resveratrol might be beneficial to the brain. The brain has more oxygen consumption than any bodily organ, about 20% of all the body's consumption. The brain therefore produces more free-radical damage, but the brain has especially low levels of antioxidant defense enzymes.

One recent study has revealed that resveratrol had protective effects against brain damage caused by a chemical that kills acetylcholine neurons. Injection of this toxin into the brain of rats impaired their memory performance in two kinds of maze tasks. The impairment was significantly reduced by repeated injection of resveratrol (10 and 20 mg/kg) pr day for 25 days, beginning four days before the toxin injection.
 
Another recent study examined the effect of dietary supplement on working memory in mice.  Groups of young adult and aged mice were put on a resveratrol-supplementd diet for four weeks before being injected with a cytokine to induce inflammation and accelerate aging. Mice were then tested for their ability to remember what they learned in a commonly used spatial memory task in a water maze. The dietary supplement significantly reduced memory impairment in the aged group, but not in the young adults. The lack of benefit in young adults was a little misleading, in that there was a "ceiling effect" in that the young adults, even though given cytosine, were already performing at near-mazimum levles. Cytosine had clear impairing effects in the contol aged mice, but much less so in the resveratrol-treated aged mice. In other words, aging makes an animal more susceptible to toxic chemicals, and thus there is more opportunity for any beneficial treatment to become manifest.

The memory studies have appeared only in the last year or so and are confined to laboratory animals. The beneficial effects may occur only in preventing damage, as with diabetes or other kinds of brain injury. Benefits may also be imperceptible in the young.

The open question is whether resveratrol will help cognitive function in humans, especially healthy humans.But you can be sure that research on humans will become intense. Positive memory-enhancing results in humans have alredy been published for consumption of blueberries, in which resveratrol is a major ingredient.

One of the first such randomized controlled trials of resveratrol effects on memory in normal older adults.has been launched in 2010 by Todd Manini and Steven Anton at the University of Florida's Institute of Aging.


What foods besides red grapes have resveratrol? The most likely other sources you would eat or drink are blueberries, cranberries, and peanuts. It is not likely that you could drink or eat enough of such substances to get enough resveratrol to do any good. Highly concentrated supplements are coming on the market. I haven't given up my two glasses of red wine each day, but I have started taking one of the supplements. I haven't seen any reports that these high doses of resveratrol are toxic.

Sources:

Abraham, J., and Johnson, R. W. 2009. Consuming a diet supplemented with resveratrol reduced infection-related neuroinflammation and deficits in working memory in aged mice. Rejuvenation research. 12 (6): 445-453.  DOI: 10.1089/rej.2009.0888

Harkiumar, K. B., and Aggarwal, B. B. 2008. Resveratrol.. A multitargeted agent fo age-associated chronic diseases. Cell Cycle 7:8, 1020-1035.

Kumar, A. et al. 2007. Neuroprotective effects of resveratrol against intracerebroventricular colchicine-induced cognitive imapirment and oxidative stress in rats. Pharmacology.79 (1): 17-26. DOI: 10.1159/000097511

Schmatz R, et al. 2009. Resveratrol prevents memory deficits and the increase in acetylcholinesterase activity in streptozotocin-induced diabetic rats. Eur J Pharmacol. 2009 May 21;610(1-3):42-8. Epub 2009 Mar 19.

Wednesday, March 31, 2010

Inaccurate and Biased Beliefs About Learning and Memory

A very sophisticated and comprehensive set of 12 experiments confirms what experienced teachers have long known: students over-estimate how much they know and under-estimate the value of repeated study of the same material. This bias may apply to everyone, but the study was performed on college students. UCLA researchers studied the reliability of people's ability to judge how well they had remembered something just studied and to predict how well they could remember if they went over the same material in several sessions.

They asked the students to look at a list of word pairs and make two estimates: one a judgement of how well they remembered what they just studied and the other a prediction of how well they would be able to remember the words after subsequent study of those same word lists.

When asked after a given study trial to judge how well they thought they remembered, students' judgment of their knowledge was not confirmed by actual performance on the test.That is, they over-estimated how much they had learned.

Amazingly, students predicted little or no learning improvement would occur with repeated study sessions, yet they actually showed large increases in actual learning with repeated study. The change in predicted performance was about the same, irrespective of whether the word pairs were deemed easy or hard to remember. However, the actual performance benefit of extra study was especially  marked for the hard-to-remember words.

Other studies have shown that people fail to predict accurately how much their memory of specific learning will deteriorate over time after the intiial learning.

Why does this matter? Well, it affects how well one manages learning tasks; that is, choosing the best activities that will create lasting memories, as for example, students choosing how and when to study.  The implication is that students don't study as much as they should because they don't appreciate the value of extra study, especially for hard-to-learn material. They also don't study as much as they need to because they think they have learned more than they really have.

Is the problem that students are generally not as smart as they think they are? Or do they fail to study more because they don't correctly realize how much it would help? The ultimate consequence is that students tend to study too little and give up too quickly.

The authors suggest that these inaccurate beliefs and the negative consequences just reflect normal psychology. They do not consider that mental laziness could be a factor. Nor do they consider that this effect might be age-specific.

This may also relate to an observation that has puzzled me ever since I wrote my original book on memory improvement. Students have not been as interested in what the book had to say as I expected. Nor do they show as much interest as I anticipated in attending my lectures on the subject. At one unversity where I recently gave a well-advertised talk on how to improve memory, not one student showed up -- only faculty. Older adults, in general, seem to realize they need to work on their memory. Students tend to think they are either just fine as they are or can't improve.

A related matter is that students don't appreciate the value of testing in enhancing memory. This value was confirmed in the present study, and I have elsewhere discussed similar findings. Testing forces retrieval of stored information and that retrieval is a strong rehearsal process that reinforces the memory.

Source:

Kornell, N. and Bjork, R. A. 2009. A stability bias in human memory: overestimating remembering and underestimating learning. J. Exp. Psychol. 138 (4): 449-468.

Monday, March 15, 2010

Vitamin D and Memory

A general rule regarding memory and nutrients is that most dietary supplements are without effect unless a person has an inadequate diet. One nutrient of special interest is vitamin D. Vitamin D is synthesized in the skin from exposure to sunlight, but many people don't get enough sunlight every day. Sun-tan lotions, designed to reduce the risk of skin cancer, also reduce the likelihood that the skin can make enough vitamin D. Particularly vulnerable populations include Blacks and elderly who are confined indoors. Also the ability of skin to synthesize vitamin D declines with age.

Vitamin D and its receptors are found throughout the body. In recent years, scientists have learned that it contributes to normal cognitive function, including memory. Vitamin D increases the brain neurotransmitter chemical called acetylcholine, which is the most important transmitter for creating conscious arousal and attentiveness. Vitamin D also stimulates synthesis of nerve growth factor, which can promote growth of nerve terminals.

A recent study has confirmed results from another lab suggesting that normal brain function requires vitamin D. Participants, 1,766 adults aged 65 years and older, were evaluated to compare blood levels of vitanim D precursor and cognitive ability. Lower levels occurred in the subset of people who were cognitively impaired, compared to the normal subjects.

Another independent study reports similar findings. The study examined 3,133 men aged 40 to 79 at eight test centers across Europe. Men who had a better memory and were quicker to process information had higher levels of vitamin D. Men with 35 nanomoles per litre or less of vitamin D in their blood performed poorly.

These are only correlational studies, but they do suggest that increasing dietary vitamin D can improve memory in people who are vitamin D deficient. This idea awaits experimental verification. In the meanwhile, taking modest doses of vitamin D (use the D3 version, about 1,000-2,000 I.U. per day) is probably a good idea.

Sources:

Llewellyn. D. J. 2009. Journal of Geriatric Psychiatry and Neurology, Vol. 22, No. 3, 188-195 OI: 10.1177/0891988708327888

Lee, D. M. et al. 2009. J Neurol Neurosurg Psychiatry 2009;80:722-729 Published Online First: 21 May. doi:10.1136/jnnp.2008.165720

Monday, March 08, 2010

A Handy List of Memory Tips

One of the followers of this blog called my attention to a useful web site that has a list of 100 things you can do to facilitate memory. Several items deal with remembering names, and others with remembering numbers and lists. Much of this information is also in my book.

I have some quibbles with some of the material, such as recommended foods. The hoopla over gingko balboa, for example, has not been replicated by research. Certain other foods are only beneficial if you are nutritionally deficient.

I particularly like the lists of things you can do to organize information, and even store it conveniently (as with sticky notes, Evernote, etc.) so you don't have to memorize everything.

Check it out: http://www.accreditedonlinecolleges.com/blog/2010/100-amazing-memory-hacks-to-maximize-your-brain/

By the way, if you have been following my blog, you will have noticed that it is starting to attract a following. I even get fan mail.

Sunday, March 07, 2010

More Bad News for Multi-tasking

Memory formation is often prevented when one event follows too soon after an initial learning event. It is also true that memory of initial learning events can be blocked if you try to learn two things at once. In fact, learning may be disrupted for both things.

In a recent test of this phenomenon, a group of 29 people (17 to 30 years of age) was trained to discriminate two sound pips that differed in length by a fraction of a second. In one group of subjects, the training occurred consecutively, which ordinarily produces some inefficiency with learning because the second task interferes with remembering the first. In this study, some learning did occur, in spite of the sequential tasks. However, results from another group of subjects revealed that when practice on the two tasks was interleaved, there was no learning on either condition.

This indicates that acquistion (initial learning) is vulnerable to multi-tasking, perhaps even more so than when learning of one task is followed too soon by another learning task. In other words, multi-tasking can interfere with initial learning, just as it does with formation of memory.

Source: Banai, K. et al. 2010. Learning two things at once: differential constraints on the acquisition and consolidation of perceptual learning. Neuroscience. 165: 436-444.

Monday, February 22, 2010

More Evidence that Naps Help Memory

I have mentioned before the value of naps for improving the formation of memories. Another recent student confirms this conclusion. Matthew Walker and colleagues an the University of California at Berkeley divided 39 young adults into two groups. At noon, all the participants took part in a memory exercise that required them to remember faces and link them with names. Then the researchers took part in another memory exercise at 6 p.m., after 20 had napped for 100 minutes during the break.

Those who remained awake performed about 10 percent worse on the tests than those who napped, Walker said. Students take note: 10% can be the difference between an A and a B.

Source: Walker, Mathew. 2010. Current Models of Mechanisms of Sleep-Dependent Memory Presentation at the annual meeting of the American Association for the Advancement of Science meeting, San Diego, Feb. 21.

Thursday, February 11, 2010

More on the Benefits of Blueberries

In several earlier posts, I discussed experiments that indicate blueberries can improve memory. There is a more recent study in 9 older adults (average age was 76) who were showing early signs of deterioration in memory capability. For 12 weeks, the subjects were given daily doses approximately 2.5 cups (exact amount adjusted according to body weight) of juice made from commercially available frozen wild blueberries. Berries were thawed, pressed, filtered, pasteurized, and then bottled. A comparison group drank the same amount of fake blueberry juice.

The subjects were instructed to refrigerate the juice at home and to take prescribed daily quantities in equal, divided dosages with the morning, midday, and evening meals. Memory tests (word-pair association, word list) were given before and after the test period. Significant gains in memory ability were seen in the blueberry group. Scores on both kinds of memory tests increased about 33%.

Additionally, there was suggestive evidence that blueberry juice reduced signs of depression and lowered blood glucose levels. This needs to be pursued in future research.

In an earlier post I had summarized a study that showed that milk protein interfered with the blueberry effect. Presumably other proteins could also interfere. In other words, I am suggesting that even better results might be obtained if the juice is taken on an empty stomach (assuming of course that this does not cause upset stomach).

The beneficial effects of the blueberries are thought to be linked to their flavonoid content - in particular anthocyanins and flavanols. The exact way in which flavonoids affect the brain are unknown, but they have previously been shown to cross the blood brain barrier after dietary intake.

Source:
Krikorian, R. et al. (2010) Blueberry supplementation improves memory in older adults. J. Agricultural and Food Chemistry. doi: 10.1021/jf9029332

Monday, January 25, 2010

What's the Right Amount of Homework?

When I ran for election to my local school board, one of my campaign planks was to promote homework. I lost. Many parents objected to my platform, often because homework would interfere with their kids' extracurricular activities or with their part-time job. One parent said to me, "We don't want any homework. My son needs that time to work at his job." I asked, "Why does he need to work?" She said, "Well, to pay for his truck for one thing." "Why does he need a truck?" I asked. Her reply: "Well, you dufus, to get to his job!"

A Duke University neuroscientist, Harris Cooper, posted in The Sacremento Bee on Jan. 17, 2010 some of his findings from research on this topic. He pointed out that an earlier Associated Press poll found that 57% of parents thought their kids got about the right amount of homework. Another 23% thought there was too little homework and 19% thought there was too much.

Harris was interested, not so much in parent opinion, but about the question of whether or not homework helps test performance. When he and his helpers looked at various published homework studies, they found that the effect varied by grade level. Comparing students who were assigned homework with students assigned no homework but who were similar in other ways suggested that homework can improve students' scores on the class tests that come at the end of a topic. Students assigned homework in second grade did better on math, third- and fourth-graders did better on English skills and vocabulary, fifth-graders on social studies, ninth- through 12th-graders on American history and 12th-graders on Shakespeare.

He finds that practice assignments do improve scores on class tests at all grade levels. A little amount of homework may help elementary school students build study habits. Homework for junior high students appears to reach the point of diminishing returns after about 90 minutes a night. For high school students, the positive line continues to climb until between 90 minutes and 2 1/2 hours of homework a night, after which returns diminish.

What nobody seems to have studied is the question of what kind of homework is most effective. Options include busy work such as filling out work sheets, problems to solve, projects to complete, Web quests, essays to write, and various other kinds of tasks. I would expect that the nature of the homework makes a big difference in the effectiveness of learning and in attitude about school.

All forms of homework can help memory formation. Rehearsal of learned material soon after it is learned is a key to efficient memory formation. In my opinion, failure of a teacher to assign homework is educational malpractice.

Tuesday, January 19, 2010

Unreliable Memory


It is one thing to forget. It is quite another to remember, but remember wrongly. Everyday experience reveals how commonly people remember things wrongly. Discuss with most anybody what each party said in a past argument or controversy, and it typically happens that people remember things differently. Somebody has to have it wrong. Such "false memories" commonly contaminate eye-witness reports of accidents and crimes.

This possibility came up in a recent a court case in Massachusetts, where a Catholic priest was convicted of sexual molestation of a child. The accuser, now an adult, ostensibly had suppressed the memories, which surfaced later in psychological counseling. On the basis of this resurrected memory, the priest was convicted and the conviction was upheld on appeal by the Massachusetts' Supreme Court. Scholarly literature supporting the notion that real memories can be suppressed and later retrieved provided the basis for believing the charges against the priest.

However, there is other scholarly literature, apparently not persuasive in this case, that asserts that this is "junk science" and that false memories are common. I concur with the news release's statement: "Experiments have shown that false memories can be created that feel just as valid as real ones and cannot be distinguished from real memories."

Our legal system has not really come to grips with false memory. But there is a growing trend to be skeptical of eye-witness testimony. It is increasingly hard to get a conviction if the only evidence against the accused is a single eye-witness report. Perhaps, in the interests of justice, that is best. There is a whole scholarly literature on false memory, including books, and I reviewed much of this in my memory book.

So, the real issue in court cases like this is that the resurrected memory may or may not be true. If there is no other evidence and it is only one person's word against another, how can you tell what the truth is? The same problem exists when people have differing recollections of something that happened in the past. Somebody got it wrong. Who got it right?


Source: UPI press release, http://www.upi.com/Top_News/US/2010/01/17/Repressed-memory-conviction-upheld/UPI-93911263709673/

Friday, January 15, 2010

Learning Versus Memory

Versus? Learning and memory are different, but like two sides of the same coin. What is the difference? Learning is the acquiring of new information or skills. Memory is the remembering of what was learned. You can’t have memory without learning. You can, of course, have learning that you forget.

Learning involves at least four major processes. It all begins with registering new information. This is the stage when information is detected and encoded in brain. Paying attention obviously facilitates the registration process. Multi-tasking can create an information overload in which much of the information never gets registered. Example: a car driver who is all wrapped up in a cell phone conversation may not realize she just ran a stop sign or cut off the driver behind her in the next lane. Another example comes with reading. Reading comprehension (learning) depends heavily on the eyes actually seeing each cluster of words. The reader needs to focus on words, not letters, and needs to think about what the words mean. Likewise in images, what you learn from an image depends on the details in it that you actually notice and think about.

Next is integration. The brain likes to classify, categorize, and organize its information. Thus, new information has to be fitted into existing learned schema. This is the stage where associations are made with existing memory. Brains are really good at detecting and constructing relationships. If a given relationship is not immediately obvious, the brain may figure it out and remember it. Constructing such relationships is an integral part of the learning process.

Associations can be constructed subconsciously. If two things happen at the same time or go together in some other way, even the simplest of brains can learn the association. Moreover, cueing of relationships can produce what is called conditioned learning. We all have heard about Pavlov’s dogs. But even animals as primitive as flatworms can exhibit conditioned learning. If worms are shown flashes of light, not much happens. If they are given mild electrical shocks to the body, the body contracts. If then a flash of light is delivered just prior to an electrical shock, after enough repetitions, the worm starts contracting when it first detects the light, before any electrical shock is delivered.

Associations are still more powerful when they are consciously constructed. This is the stage where you ask yourself such questions as: Where does this information fit with what I already know? How does this relate to other things I could learn about? What value do I place on this information? How invested in using or remembering it should I be?

Then there is understanding. You can, as I did, pass college calculus by using the right formulas for given problem types, and yet not really understand what is going on with the equations. To understand, you need to answer such questions as: Is this consistent with what I thought I knew? What is missing or still confusing? What can I do with this information? What else does it appoly to, how can it be extended? What is predictable?

Learning is not complete without understanding. Understanding also creates a basis for generate insights and creative syntheses, and these in turn advance the depth and rigor of the original learning. Insights typically come from deduction or induction. Deduction is the Sherlock Holmes process of using one fact or observation to lead logically to another. Induction is the Charles Darwin process of using multiple, apparently unrelated, facts or observations to make a synthesis that accommodates them all.

Finally, there is learning to learn. This is the process of learning the paradigm, the “rules of the game,” that allows you to transfer one learned capability to new learning situations that are related. At this point, one has reached a threshold where the more you know, the more you can know.

One of the first experimental demonstrations of this phenomenon was by H. C. Blodgett in 1929. He studied maze behavior in rats, scoring how many errors they made in running the maze to find the location where a food reward was placed. Rats ran the maze once per day on successive days. The control group ran the maze and found the food, with number of errors decreasing slowly on successive days as they learned where in the maze the food was. Experimental groups ran the maze daily for three or seven days without any food reward. Naturally, they made many errors because there was nothing to learn. However, when they subsequently were allowed access to a food reward, the number of errors dropped precipitously on the very next day’s trial. In other words, the rats had been learning about the maze, its layout, number of turns, etc. during the initial explorations when no reward was available.
Blodgett called this “latent learning,” an idea expanded and formalized some 20 years later in the “Learning Set” theory of Harry Harlow. Harlow studied visual discrimination learning in monkeys and observed that visual and other types of discrimination problems progressed more quickly as a function of training on a series of different, but related problems.

These discoveries were born of necessity, arising from the need to use the same monkeys over and over in a wide variety of experiments because the Harlow lab was so under-funded. Increasing the number of problems on which monkeys were tested led to the observation that the monkeys’ general learning competence improved over time. This of course parallels the general common experience of maturation of children.

Harlow developed the prominent theory that learning any task is associated with implicit learning capabilities that can generalize to other related learning situations. The concept relates simpler trial-and-error learning to more advanced insightful-like learning, which he regarded as a mental ability that depended heavily on prior learning sets. Ability to form learning sets varies with species. Monkeys do it better than dogs or cats, and humans do it best of all.The reasons for human superiority in learning no doubt include the rich connections among various brain areas that can support and integrate more learned associations.