IQ Changes in Teenagers

Common wisdom asserts that your IQ is fixed. Of course, the various “multiple intelligences” change with personal life experiences and growth, but we usually consider the standard IQ score to be inherent and unchangeable. But even the standard IQ measure changes during different life stages. Clearly, the IQ of young children changes as they mature. Several studies even show that working-memory training can raise the IQ of elementary-school children. More than one analyst claims that a rigorous PhD program can raise IQ in adults. Most obvious is the decline of IQ in those elderly who do not age well because of disease.

A neglected segment along the age spectrum is the teenage years. Now, evidence indicates that this age group experiences IQ changes ranging from a decline to an increase. A study of this issue shows that both verbal and non-verbal IQ scores in teenagers relate closely to the developmental changes that occur in brain structure during the teenage years. Longitudinal brain-imaging studies in the same individuals reveal that either increases or decreases in IQ occur coincident with structural changes in cerebral grey matter that occur in teenagers.

The study conducted MRI brain scans and IQ tests on 33 normal adolescents in early teenage years and then again in late teenage years.  A wide range of IQs were noted, 77 to 135 in the early group and 87 to 143 in the late group. For any given individual, the change in IQ score changed from -20 to +23 for verbal IQ and -28- to +17 for non-verbal IQ. Correlation analysis revealed that increases in IQ were associated with increased in cortical density and volume for brain regions involved in verbal and movement functions.

The implications are profound, especially as they relate to the local environment of a given teenager. What happens during the teenager years apparently changes brain structure and mental ability. Many influences likely damage the brain, such as drug abuse, or social stress, or poor education and intellectual stimulation. Conversely, the data indicate that positive benefits to both brain structure and mental capability can result from a mentally healthy environment and rich educational experience.

The data suggest that all the emphasis on pre-school and “Head Start” initiatives may diminish our attention to the key role played by middle school and early high school. This confirms what many of us always suspected, namely that our society tends to insufficiently nurture “late bloomers.” Maybe the early high achievers who fail to live up to their promise do so, because we wrongly assume they can manage without much help. Parents, educators, and education policy makers need to take notice.

Few books can change a person's future. One of them could be my book, Better Grades, Less Effort, which explains the learning tips and tricks that I used to become valedictorian, when a high school teacher said my modest IQ did not justify the high grades I was making. Teachers predicted I "would have trouble with college." Really? I went on to be an Honors student in three universities -- including graduating early with a D.V.M. degree and securing a PhD in two-and-a-half years. My IQ documented that I was not so smart. I believe that poor learning skills are what hold back most students from superior achievement. This book can change a person's life, as my own experiences with learning how to learn have changed my life. I suspect it helped my brain development as well.

Source:

Ramsden, Sue et al. (2011). Verbal and non-verbal intelligence changes in the teenage brain. Nature. May 17. Doi:10:1038/nature10514.

Lifestyle Effects on Working Memory Ability

On multiple occasions, readers of my learning and memory blog posts asked me what they could do to improve their working memory. This is an important and very practical question. Working memory affects all aspects of life success: personal, educational, and professional. I usually tell them to practice attentiveness and concentration. But I probably should tell them to adapt a healthier lifestyle.

For over a decade a variety of studies have implicated lifestyle in memory function. A rigorous new study confirms these results. An Israeli research team studied 823 participants, aged 22-37 years, using brain scans taken during a difficult memory task, post-scan memory tests, and numerous measures of health and lifestyle. The brain scans identified the brain areas that particularly engage in working memory tasks, most important of which were the dorsolateral prefrontal cortex, parietal cortex, and anterior cingulate cortex. These then served as a frame of reference to check for correlations with health and lifestyle.

The key finding was a strong correlation between activity in working-memory brain areas and health and lifestyle. With all behavior/health variables considered together, the highest positive correlation occurred, in order, with fluid intelligence, reading, spatial orientation, picture vocabulary, several memory tests, and attentiveness.  

They observed an opposite correlation for such specific life-style indicators as large body mass index and a variety of unwise lifestyles such as binge drinking, and regular smoking. Health variables that correlated negatively with working-memory brain areas included high body-mass index, high blood pressure, poor glucose regulation.

The healthy lifestyle variables also correlated with other cognitive functions, such as fluid intelligence, reading/language skills, visuospatial orientation, sustained attention, mental flexibility and emotional intelligence, and physical endurance. Thus, the working memory benefit from healthy lifestyles seems to reflect a general improvement of brain function that good health confers.

The principle confirmed here supports the underlying theme of my recent e-book for seniors, which explained how memory serves a function like a canary in the coal mine. Memory decline is a warning signal of a damaged brain. That book explains the healthy life styles that people should be using as they age in order to keep the brain healthy and prevent memory deterioration. Changing lifestyle after the damage has already occurred may be too late. The point is that young people with healthy lifestyles have better brain function, and those lifestyles will help both body and brain to age well.

I recently published a book, “To Tell the Truth: Save Us from Concealment, Half-truths, Misrepresentation, Spin, and Fake News.” It is an inexpensive ($3.99), e-book now available at Amazon. At Smashwords.com you can choose among several e-book formats, including pdf.

Sources:

Klemm, W. R. (2014). Improve Your Memory for a Healthy Brain. Memory Is the Canary in Your Brain's Coal Mine. https://www.smashwords.com/books/view/496252

Moser, D. A. et al. (2017). An integrated brain-behavior model for working memory. Molecular Psychiatry. Doi: 10.1038/mp.2017.247

Memory Training Produces Lasting Effects

I first got interested in memory training at age 15 when my dad was a salesman for the Dale Carnegie leadership course, which included a section on memory training. My dad taught me some tricks that enabled me to memorize the gist of what was on every page of a magazine, by page number, in 30 minutes. I used to put on demonstrations for prospective enrollees. Before the recruitment meeting started, the leader would tell the audience, "Everybody see Billy here. Stand up Billy. I am going to give him this latest magazine issue, which he has never seen, and let him study it for 30 minutes. Then we will interrupt the meeting and you can ask him what is on any given page. Or you can tell him what is on a page, and he can tell you the page number." To my own astonishment, I could do it and it was not that hard. The basic gimmick was first to memorize a number code that converted page numbers into a visual image. For example, the code for 20 was "noose," as in a hangman's noose. Then I would convert the content on page 20 to an image or image series that captured the gist of the content. Then I would link the page-code image and the content image. For example, if the content on page 20 was about Elvis joining the army and his boot camp experiences, I would picture Elvis, guitar and costume, being trucked off in a military truck to a boot camp, where they put him through gymnastic exercises, marching, and simulated combat, and then they hung him. This idea and many other mnemonic devices are explained more fully in my book, Memory Power 101.

At the time, I wondered if this kind of mental exercise would have some sort of spill-over, lasting effect. Hopefully, it would help me in school. I think it did (I never made less than an A), but I never had an objective way to verify that.

Most readers have probably heard about "memory athletes," people who use mental imaging mnemonic devices to accomplish astonishing feats of memory. Such athletes can, for example, memorize in five minutes 550 words or the sequence of four shuffled decks of cards.

Until now, there were few studies of whether the brains of such athletes are changed in any lasting way by the memory training.

One indication of lasting change had been reported in London taxi drivers who were revealed by brain scans to have an enlarged hippocampus, a large paired structure in the brain that forms memories and also maps spatial locations (London streets are convoluted in their layout and notoriously difficult to learn).

A more direct test of brain change has been recently reported. In the first experiment, 23 of the top 50 world-ranked memory athletes were compared with control normals of similar age, gender and IQ.  Brains were scanned in all subjects under two conditions: first, while they were relaxed and letting their minds wander, and second, while they were trying to memorize a list of 72 words.

Not surprisingly, the memory champions missed only two words on average when recalling the list 20 minutes later, whereas their controls missed nearly half. The brain scans revealed patterns of connectivity among various brain regions in the memory champions.

Investigators then wanted to know if memory training of the controls would produce lasting changes in them. Thus, the controls were separated into three groups: one was asked to practice the Method of Loci memory technique for half an hour every day for a total of six weeks. A second group practiced a very challenging working-memory task, the dual N-back, in which they had to memorize a sequence of spoken words while paying attention to the locations of a moving square on the computer screen, and identify when a letter or position matches one that appeared earlier. The last group just lived their normal life without memory training for the test period of six weeks.

When tested right after training on memorizing a random list of words, only the Method of Loci group showed improved memory. Comparison of brain scans before and after the six weeks revealed connectivity changes, much like those of memory champions. Also, the change in connectivity was a reliable predictor how well they performed in the memory test. Moreover, the connectivity changes and improved memory ability persisted for at least four months afterwards.

The authors of the study report could not explain why dual N-back training had no lasting effect (other than getting better at N-back tests), as might be expected because it is a very demanding task. But I think the reason is that N-back training involves a different aspect of memory that does not generalize to memorizing word lists.

Anyway, I feel better now that my memory experiences at 16 have served me well in the succeeding years. This is consistent with what I had learned about neuroplasticity as an adult neuroscientist: the brain has to change to store what you learn in memory. How that happens is explained in another book of mine, Mental Biology.

Sources:

http://www.worldmemorychampionships.com/

Dresler, M., et al (2017). Mnemonic training reshapes brain networks to support superior memory. Neuron, 93: 1-9.

Klemm, W. R. (2012) Memory Power 101. New York: Skyhorse.

Klemm, W. R. (2014). Mental Biology: The New Science of How the Brain and Mind Relate. New York: Prometheus.

See rave reviews of "Memory Medic's" books at WRKlemm.com

Available at Amazon, Barnes and Noble, and the publisher web sites.

Training the Brain to Control Negative Emotions

The human brain contains a distinct network that serves as its executive agent. This network is primarily based in the dorsolateral prefrontal, parietal, and cingulate cortices. It regulates the many “top down” neurobehavioral functions that are so characteristic of human brain. Deficiencies in the function of this network underlie numerous neuropsychiatric conditions, but even underlie much of the failings of us all. The ability to regulate emotions and direct rational actions is typically associated with success in life, and inability to do so often leads to dire consequences.

This network can be trained to develop more robust capacity for executive control. This, as we all experience, is what parenting and schooling are about. Such training is especially crucial in early childhood when the challenges of school are first encountered. Even so, such training takes many years and for most of us may never be completed.

The question arises: can such executive control training be expedited? One possibility has recently arisen from several studies showing that working memory capacity can be expanded by a relatively short training time, and in the process general intelligence may be improved. Since the same system that determines intelligence is also operative in executive control, it seems reasonable that working memory training might also enhance executive control. To pursue this possibility in a specific context, researchers have hypothesized that inappropriate or maladaptive behaviors might be reduced by effective working memory training based on emotion-laded stimuli.

In a study by Suaznne Schweizer and colleagues in England, subjects in their early 20s were assessed for emotional control before and after 20 training days of 20-30 minute sessions. The experimental groups received dual n-back training with a simultaneously presented face and a word that was either emotionally negative or neutral. After each picture-word pair, subjects were to press a button to indicate if either or both members of the pair matched the stimulus presented n-positions back. Tests began with n = 1 and increased as subjects gain proficiency.

Not surprisingly, errors in both trained and untrained subjects increased at levels beyond n = 1, and the error rate was comparable for both groups. Results also indicated that subjects reported less distress when they consciously willed to suppress the distress compared with the null state of just attending to negative stimuli. But this distress reduction occurred only in the emotional working memory training group.

No change in neural activity levels was indicated in brain scans as a result of placebo training, but significant increases occurred in the executive control regions of interest as a result of emotional working memory training, irrespective of the level of n-back achievement.

The study also compared emotional responsivity before and after training. Subjects were asked to just pay attention or to pay attention and cognitively suppress their emotional reaction. Subjects rated their emotions on a numerical scale from negative to positive while viewing films that were emotionally neutral (such as weather forecasts) or that were emotionally disturbing (such as war scenes, accidents, etc.). Training caused no change in the group that viewed only neutral images, but in the groups viewing disturbing scenes, training decreased the perceived distress in a group told just to attend the scenes and was even more effective in the group told to suppress emotional reaction.

The emotional working memory training produced benefits that transferred to the emotional response task. Trained subjects not only regulated their emotions better but also developed greater brain-scan activity during the emotional task in the predicted brain regions of interest, the executive control loci. In other words, the training actually changed brain function on a lasting basis. Traditionally, we have always thought that the sole benefit of n-back memory training is to expand the amount of information that can be held in working memory. But now we see that such training can improve our ability to control emotions. Emotional working memory training improves the ability to suppress disturbing emotional responses and does so presumably because the executive control network is more activated. Thus, such training might also enhance many executive control functions, particularly responses to emotionally disturbing circumstances. A new tool for self-control may have been discovered.

Sources:

Banich, M. T., Mackiewicz, K. L., Depue, B. E., Whitmer, A. J., Miller, G. A. , Heller, W. (2009) Cognitive control mechanisms, emotions and memory: a neural perspective with implications for psychopathology. Neurosci. Biobehav. Rev. 33, 613-630.

Beck, A. T. (2008) The evolution of the cognitive model of depression and its neurobiological correlates. Am. J. Psychiatry. 165, 969-977.

Schweizer, S., Grahn, J., Hampshire, A., Mobbs, D., and Dalgleish, T. (2013).  Training the emotional brain: improving affective control through emotional working memory training. J. Neurosci. 33(12), 5301-5311.

Readers of this column can learn more about n-back training and numerous other ways to improve brain function in "Memory Medic's" e-book, Improve Your Memory for a Healthy Brain. For a limited time only, this book is priced at 99 cents, available in all formats from Smashwords.com.

                                                          

Jazz Changes the Brain

To follow up my prior post on jazz, I just read a scientific report published last week that suggests that training of musical creativity in jazz causes long-lasting changes in brain function. In this study, musicians completed a questionnaire that allowed researchers to know the extent of each subject's prior classical and jazz training. Functional MRI brain scans were taken with subjects lying down on their back with a piano keyboard on their lap, playing improvisations with their right hand. Ear phones allowed players to hear their improvisations.

Brain scan showed distinct activity differences in the jazz musicians and that difference was greater in those with longer jazz histories. Past improvisation experience increased the functional bilateral connectivity of the dorsal premotor cortex, the pre-supplemental motor areas of cortex, and the dorsolateral prefrontal cortices. Decreased activity connectivity was noted in executive control frontal-parietal areas. Thus, it would seem that creativity training, in jazz at least, changes the brain at a network level. Presumably, these connectivity changes were created by past histories in learning jazz and no doubt facilitated improvisation by automating some of the neural functions needed to perform it.

How do we interpret the decreased activity in executive-control areas of cortex? Multiple other brain-scan studies in other contexts have indicated that as a brain becomes proficient in a certain task, apparently less neural tissue is needed to perform the task. Decreased activity can therefore indicate task mastery.
Scientists have known for a decade or more that learning and memory in general change both brain anatomy and function. Such changes are typically linked to the neural requirements for performing specific kinds of tasks. This study of classical and jazz musicians follows on prior studies showing that musical training does change the brain. For example, violin players have enhanced neural activity in the motor cortex controlling hand movements. The relative size of the left and right motor cortex differs between piano and string players.

The importance of this present study is that it demonstrates that the brain change depends on the kind of musical training and appears to be selective for improvisation. Moreover, musical improvisational training affects more than just control over movements and extends to cognitive functions needed to improvise. Improvisation is a creative act that apparently recruits cortical circuits to support it and in the process rewires the brain to facilitate improvisation.

Improvisation relies heavily on memory of previously learned musical patterns and implementation strategies. Jazz players call this "musical vocabulary." Thus, jazz players have to become musicians first, then learn how to improvise. Because memory is a "process in a population, not a thing in a place," neural representation of musical vocabulary is probably widely distributed, and the brain must learn how to recruit connections from multiple brain areas and integrate them in real time in the prefrontal and movement-control parts of the brain, which apparently generate creative ideas and implement them.


Source:

Pinho, A. L. et al. (2014) Connecting to create: expertise in musical improvisation is associated with increased functional connectivity between premotor and prefrontal areas. J. Neuroscience. 34 (18): 6156-6163. doi: 10.1523/JNEUROSCI.4769.13-2014.

                         Memory Medic has a new book being distributed by Random House: 

                         Mental Biology. The New Science of How the Brain and Mind Relate.

Cursive Writing Makes Kids Smarter

Ever try to read your physician’s prescriptions? Children increasingly print their writing because they don’t know cursive or theirs is unreadable. I have a middle-school grandson who has trouble reading his own cursive. Grandparents may find that their grandchildren can’t read the notes they send. Our new U.S. Secretary of the Treasury can’t (or won’t) write his own name on the new money being printed.

When we adults went to school, one of the first things we learned was how to write the alphabet, in caps and lower case, and then to hand-write words, sentences, paragraphs, and essays. Some of us were lucky enough to have penmanship class where we learned how to make our writing pretty and readable. Today, keyboarding is in, the Common Core Standards no longer require elementary students to learn cursive, and some schools are dropping the teaching of cursive, dismissing it as an “ancient skill.”[1]

The primary schools that teach handwriting spend only just over an hour a week, according to Zaner-Bloser Inc., one of the nation's largest handwriting-curriculum publishers. Cursive is not generally taught after the third grade (my penmanship class was in the 7^th grade; maybe its just coincidence, but the 7^th grade was when I was magically transformed from a poor student into an exceptional student).

Yet scientists are discovering that learning cursive is an important tool for cognitive development, particularly in training the brain to learn “functional specialization,”[2] that is capacity for optimal efficiency. In the case of learning cursive writing, the brain develops functional specialization that integrates both sensation, movement control, and thinking. Brain imaging studies reveal that multiple areas of brain become co-activated during learning of cursive writing of pseudo-letters, as opposed to typing or just visual practice.

There is spill-over benefit for thinking skills used in reading and writing. To write legible cursive, fine motor control is needed over the fingers. Students have to pay attention and think about what and how they are doing. They have to practice. Brain imaging studies show that cursive activates areas of the brain that are not affected by keyboarding.

Much of the benefit of cursive writing comes simply from the self-generated mechanics of hand- printing letters. During one study at Indiana University to be published this year,[3] researchers conducted brain scans on pre-literate 5-year olds before and after receiving different letter-learning instruction. In children who had practiced self-generated printing by hand, the neural activity was far more enhanced and "adult-like" than in those who had simply looked at letters. The brain’s “reading circuit” of linked regions that are activated during reading was activated during cursive writing, but not during typing. This lab has also demonstrated that writing letters in meaningful context, as opposed to just writing them as drawing objects, produced much more robust activation of many areas in both hemispheres.

In learning to write by hand, even if it is just printing, a child’s brain must:

•            Locate each stroke relative to other strokes.
•            Learn and remember appropriate size, slant of global form, and feature detail characteristic of each letter.
•       Develop categorization skills.

Cursive writing, compared to printing, is even more beneficial because the movement tasks are more demanding, the letters are less stereotypical, and the visual recognition requirements create a broader repertoire of letter representation. Cursive is also faster and more likely to engage students by providing a better sense of personal style and ownership.

Other research highlights the hand's unique relationship with the brain when it comes to composing thoughts and ideas. Virginia Berninger, a professor at the University of Washington, reported her study of children in grades two, four and six that revealed they wrote more words, faster, and expressed more ideas when writing essays by hand versus with a keyboard.[4]

There is a whole field of research known as “haptics,” which includes the interactions of touch, hand movements, and brain function.[5] Cursive writing helps train the brain to integrate visual, and tactile information, and fine motor dexterity. School systems, driven by ill-informed ideologues and federal mandate, are becoming obsessed with testing knowledge at the expense of training kids to develop better capacity for acquiring knowledge.

The benefits to brain development are similar to what you get with learning to play a musical instrument. Not everybody can afford music lessons, but everybody has access to pencil and paper. Not everybody can afford a computer for their kids−maybe such kids are not as deprived as we would think.

Take heart. Some schools just celebrated National Handwriting Day on Jan. 23. Cursive is not dead yet. Parents need to insist that cursive be maintained in their local school.

Readers who want an easy way to acquire a neuroscience background will want to know about the 2nd Edition of my e-book, “Core Ideas in Neuroscience.” Check my web site for available formats and sources (thankyoubrain.com/neurobook). Also check out the Neuro-education discussion group I just created on Linkedin (type “Neuro-education" in Linkedin’s search field).

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[1] Slape, L. “Cursive Giving Way to Other Pursuits as Educators Debate Its Value.” The Daily News, Feb. 4,

2012. http://tdn.com/news/local/cursive-giving-way-to-other-pursuits-as-educators-debate-its/article_c0302938-4f94-11e1-af3a-0019bb2963f4.html

[2] James, Karin H. an Atwood, Thea P. (2009).The role of sensorimotor learning in the perception of letter-like forms: Tracking the causes of neural specialization for letters. Cognitive Neuropsychology.26 (1), 91-100.

[3] James, K.H. and Engelhardt, L. (2013). The effects of handwriting experience on functional brain

development in pre-literate children. Trends in Neuroscience and Education. Article in press.

[4] Berninger, V. “Evidence-Based, Developmentally Appropriate Writing Skills K–5: Teaching the

Orthographic Loop of Working Memory to Write Letters So Developing Writers Can Spell Words

and Express Ideas.” Presented at Handwriting in the 21st Century?: An Educational Summit,

Washington, D.C., January 23, 2012.

[5] Mangen, A., and Velay, J. –L. (2010). Digitizing literacy: reflections on the haptics of writing. In Advances in Haptics, edited by M. H. Zadeh. http://www.intechopen.com/books/advances-in-haptics/digitizing-literacy-reflections-on-the-haptics-of-writing

Is Lack of Sleep Causing Your Brain to Shrivel?

Snore a lot? Get up frequently at night to urinate? Wake up at 2 A.M. with bright ideas or worries? All these disruptions of sleep are common and more so as we get older. Does it matter? Well, of course such awakenings disrupt our sleep, and maybe it is just inconvenient. But disrupted sleep not only is more likely with age, it may promote deterioration in mental functioning. A recent study compared the effects of sleeping behavior in young adults and seniors. The study involved assessing the memory after sleeping of 18 young adults in their 20s and 15 older adults in their 70s. The subjects were tested on 120 word sets before they went to bed, and an EEG machine monitored their brain activity while they slept. Upon awakening, they were tested once again on the word pairs, but this time they took the tests while undergoing functional  magnetic resonance imaging (fMRI) scans.

The quality of deep sleep among the older adults was 75 percent lower than the younger ones, and their memory was significantly worse the next day−55 percent worse. The scans suggested deterioration of the frontal lobe. Shrunken brains can occur from aging and shrunken brains impair thinking and memory. But is it possible we have the cause and the effect backwards. Maybe what happens in the environment, such as impaired sleeping, causes both the shrunken brain and the impaired memory. Or in other words, what causes older brains to shrink?

Scientists consider a decrease of about 2% shrinkage every 10 years as normal. That may not be normal, just what most people experience because they are not taking care of their brains. There is abundant research that shows that exercises for both the brain and body help to reduce brain atrophy.

Of course, anything that damages neurons can reduce the number of their tree-like processes and the density of their contact points with other neurons. The list of such causes is long, including: alcohol abuse, brain inflammation, certain infections, concussion, impaired blood supply, lack of intellectual stimulus, vitamin B12 deficiency. It now appears that we should add fragmented sleep to the list.

Common natural causes of fragmented sleep in older humans are alcohol abuse and sleep apnea. Also, in males, enlarged prostate causes a need for frequent urination. As I have explained in my learning and memory blog posts (thankyoubrain.blogspot.com), learning events during the day are consolidated into lasting form during the sleep at night of the same day. We don’t know exactly how sleep helps, but obviously, you have far fewer mental distractions during sleep — unless, of course you keep waking up.

Alzheimer’s Disease also causes fragmented sleep. So, it is no surprise that the brain degeneration by the disease would cause memory problems. But maybe, just maybe, it is the fragmented sleep that accelerates onset of Alzheimer’s disease. Now, this seemingly ridiculous possibility has to be taken seriously in light of new research showing that sleep-disordered breathing, as in sleep apnea, seems to increase the risk of mental decline and even dementia in older women.

Disrupted sleep may also accelerate normal aging. This is certainly true when the cause is sleep apnea, which raises blood pressure and increases the cardiovascular damage that high blood pressure causes. Blood clotting is promoted, increasing the likelihood of strokes. Obesity and diabetes are often associated with sleep apnea, and it seems that sleep apnea not only results from obesity but can promote obesity and the diabetes that often accompanies obesity. Diabetes is toxic for nerve terminals. Similar neuropathy may also be occurring in their brain. Sleep apnea causes daytime sleepiness, and that it turn reduces attentiveness and mental activity, which when sustained over many years reduces the mental stimulus and promotes atrophy of neuronal processes.

Obviously, blood oxygen drops during sleep apnea. Normally, blood is 94% to 98% saturated with oxygen. But not breathing for 30 seconds or more during sleep causes oxygen level to drop to 80% or less. Any level below 90% oxygen level is dangerous, especially to the brain which demands nearly 20% of all the body’s oxygen supply. The adult brain can only survive about four minutes once oxygen is completely cut off.

So it is entirely possible that the slipping memory we see in so many elderly is a warning sign of something much more serious. But by the time the memory deficits show up, much of the damage has already been done. Prevention is the best hope.

Source:

Mander, B. A., Rao, V.,  Brandon, B. L., Saletin, J. M.,  et al. (2013). Prefrontal atrophy, disrupted NREM slow waves and impaired hippocampal-dependent memory in aging. Nature Neuroscience  doi:10.1038/nn.3324 

http://www.livestrong.com/article/161959-what-are-the-causes-of-brain-atrophy/

Yaffe, K., Laffan, A. M., Harrison, S. L. et al. (2011). Sleep-disordered breathing, hyupoxia, and risk of mild cognitive impairment and dementia in older women. JAMA. 306 (6), 613-619. doi:10.1001/jama.2011.1115

For those who want to learn more about the brain, Dr. Klemm has just released the second edition of his e-book, “Core Ideas in Neuroscience.” See http://thankyoubrain.com/neurobook/index.htm

Behavioral Therapy Erases Bad Memories: Timing Matters

It has taken 50 years, but memory research has finally put it all together to provide practical guidance to reduce forgetting of what we need to remember and promote forgetting of useless or disturbing memories.

I have blogged before about animal studies showing that bad memories can be erased. Bad memories are often created like conditioned reflexes in Pavlov’s dogs. That is, the situational context in which bad things occur act as associational cues that help cement the memory. If the cues are repeatedly present but the bad event is not, the learned associated tends to go away.

But in both animals and humans, this “extinction” as it is called is not really permanent and the bad memories can recur.  

Memory researchers have recently discovered that when a memory is recalled, whether good or bad, there is a short time where it can be modified by new thought or experience, and then it is put back in storage (called “reconsolidation”). When this phenomenon was discovered, it raised the possibility that timing of extinction trials might influence effectiveness of treatments for anxiety. That is, better treatment results might occur if extinction is attempted during the vulnerable reconsolidation stage. In 2009, Joseph LeDoux and his colleagues demonstrated in rodents that timing of extinction trials did in fact influence the erasure of fear memory.  

This modifiable stage provides a way to treat even really bad memories, like post-traumatic stress disorder. When a soldier, for example, recalls a bomb killing a buddy, that terrible memory is subject to modification before it is re-stored. A typical modern treatment for PTSD is to inject an anxiety-reducing drug just before the bad memory is triggered that interferes with reconsolidation of memory. This process may have to be repeated many times before the bad memory is finally gone. Now a new study from the Uppsala University in Sweden has shown that bad memories can be erased without drug.

Investigators created bad memories in human volunteers by giving them an electric shock each time a certain picture was flashed on a computer screen. They repeated this experience 16 times to establish a conditioned fear response. The next day after such training, the subjects were brought back into the test room, and the fear-of-shock memory re-triggered by showing the picture that had been associated with shock. This was repeated eight times without associated shock, as a way to produce extinction. Half of the subjects received their extinction treatments at 10 minutes later in which the fearful stimulus was repeated without any shock. The other half of the subjects were given the same extinction treatment but delayed six hours, when it was presumably too late to interfere with reconsolidation.

To measure the amount of fear evoked by later presentations of the picture, investigators objectively measured the amount of fear, using a skin conductance test that measured essentially how sweaty the palms were. Signs of fear were absent in the group given extinction trials at 10 minutes when reconsolidation was still in progress. But signs of fear persisted in the six-hour group.

To pursue questions about what was happening in the brain, investigators used brain imaging, and particularly noticed activity changes in the amygdala, a structure deep within the brain that is hyperactive in the presence of fear memories. On the third day, all subjects were brought back to the lab and brain scans run when the fearful image was shown. In those subjects in the six-hour group, activity in the amygdala predicted whether signs of fear (skin conductance) would return. No such prediction occurred in the 10-min group. In other words, people who lost their fear memory, as indicated by skin sweating, also lost the signs of the memory in the amygdala. Similar effects were seen in the network of other brain areas linked to the amygdala in the processing of fear memories.

None of this should have been surprising. Back in the 1960s, I and many others conducted studies in animals that showed memory of a learning event depended on what happened shortly after the learning. We knew that this short window of time was vulnerable to other mental events that could prevent memory consolidation. Implications for education were obvious: multi-tasking, for example, introduces mental events that interfere with memory consolidation. But one wonders why it took science 50 years to apply what we knew about consolidation to the treatment of anxiety disorders. The key was the recent discovery that recall of a memory puts it back in the vulnerable position of having to be reconsolidated.

Source:

Agren, T. et al. (2012). Disruption of reconsolidation erases a fear memory trace in the human amygdala. Science. 337 (6101): 1550-1552.