Healthier lifestyle can improve memory

A healthy lifestyle can reduce the risk of delay, and may even prevention chronic diseases like heart disease, diabetes, cancer, stroke and obesity all of which have a profound impact on brain health.

Healthier lifestyle can create the mind that is alert and energetic.   It can improve memory, mental clarity, energy and mood.

By treating the body well, it should be able to enhance the ability at being able to process and recall information. Eating a good diet, minimizing stress, getting enough sleep, cutting down on alcohol and caffeine and throwing away that last pack of cigarette will al help improve brain and memory function.

Taking a regular exercise helps to increase the flow of oxygen to the brain. This, in turn, reduces the risk from suffering from disorders which can lead to memory loss, such as cardiovascular diseases or diabetes.

Research shows that to keep memory in tip-top shape, the body need to get enough rest and good quality sleep, including enough dreaming sleep. Sleeping at least eight hour, will give fresh on the next day with a sharpened memory.
Healthier lifestyle can improve memory 

Guest Post: Apples, oranges, and treating mild hypertension

- Stephen Martin, MD

A recent systematic review published in the Annals of Internal Medicine (and discussed by Dr. Lin in a previous post) revisited the potential efficacy of drug treatment for mild hypertension. The authors concluded that this treatment “in the primary preventive setting is likely to reduce the risk for several important adverse health outcomes.” This is an interesting finding, given that a 2012 Cochrane review found no evidence of mortality or morbidity benefits from drug treatment of mild hypertension. What changed?

The Annals authors explain their different conclusions as follows (italics mine): “Besides the inclusion of persons with diabetes or prior antihypertensive treatment, the disparity between the conclusions of this review and the one immediately preceding it is primarily attributable to statistical power. The present review nearly doubled the number of patients, quadrupled the number of cardiovascular events, and provides data on end points not available in the prior meta-analysis.”

Having recently examined this literature for our BMJ piece, “Mild hypertension in people at low risk,” my interpretation is different. In order to gain statistical power, the new review combined high-risk and low-risk patients with mild hypertension. This is equivalent of mixing apples—e.g., higher-risk people with diabetes and prior treatment—with oranges— people without diabetes or prior treatment of hypertension.

To summarize this systematic review a bit differently, I derived the table below from Annals Appendix Table 3 and assigned the sources of patients as being oranges (Cochrane) or apples (BPLTTC Trials):

	Cochrane (Oranges)	BPLTTC Trials (Apples)	Difference (Apples/Oranges)
Active Participants	4,478	3,364
Diabetes (%)	0	96	∞
Previous antihypertensive treatment (%)	0	62	∞
Total Deaths (#, events per participant)	77 (0.018)	230 (0.068)	3.78 (0.068/0.018)
Cardiovascular Deaths	NA*	96 (0.029)	NC^
Strokes	10 (0.002)	89 (0.026)	13 (0.026/0.002)
Coronary Events	71 (0.016)	114 (0.034)	2.13 (0.034/0.016)
Heart Failure	NA	62	NC

* NA = “Not Available,” which occurred for individual trials in the Cochrane and BPLTTC, more so the former (see Appendix Table 3 link above)

Unfortunately, these subtleties were absent from the journal’s communication to the mainstream media, which simply stated: “Blood pressure drugs likely to prevent stroke and death in patients with mild hypertension.”

There is hope yet. The paper buried a worthy point when it concluded that “… estimation of cardiovascular risk may aid prioritization in this patient group.” Rather than combining apples and oranges, we need to treat them as different fruit. Apples may benefit from treatment of mild hypertension while oranges do not. Blending them serves neither fruit well.

For now, I’ll continue to generally avoid drug treatment for my low-risk patients with mild hypertension.

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Dr. Martin is a family physician and an Assistant Professor at University of Massachusetts Medical School.

Think twice before taking Tamiflu for seasonal influenza

As the Centers for Disease Control and Prevention (CDC) reported that people who received this season's influenza vaccine were only 23 percent less likely to be diagnosed with influenza than unvaccinated persons, CDC director Tom Frieden was publicly urging high-risk patients and their physicians to use antiviral medications to prevent complications and disease transmission:

People who are sick with flu, if they're very sick in the hospital or if they have underlying, chronic medical conditions, like asthma, diabetes, heart disease, women who are pregnant, children under two and people over the age of 65 - all of these people, if they get flu, should get treated with antiviral drugs. The evidence indicates that it will shorten how long you're sick, might keep you out of the hospital and could even save your life. ... There is some evidence that suggests that taking antiviral medications may reduce the risk that you'll spread the disease to others in your family so it may be helpful for others as well as for yourself.

A previous AFP Community Blog post discussed a 2012 Cochrane review which cast doubt on the ability of the neuraminidase inhibitors oseltamivir (Tamiflu) and zanamivir (Relenza) to prevent influenza transmission, noting that after including data from unpublished, industry-sponsored, randomized controlled trials, the difference was not statistically significant.

Also in that year, a meta-analysis by Dr. Mark Ebell and colleagues concluded: "There is no evidence that oseltamivir reduces the likelihood of hospitalization, pneumonia or the combined outcome of pneumonia, otitis media and sinusitis." The authors noted that two large unpublished trials of oseltamivir in older persons and persons with chronic disease did not even show that the drug reduced the duration of symptoms, suggesting that oseltamivir might be less effective at treating influenza in high-risk groups.

In 2014, after gaining access to the complete clinical study reports from the manufacturers, the Cochrane Collaboration updated its previous review and drew the following conclusions: "Oseltamivir and zanamivir have small, non-specific effects on reducing the time to alleviation of influenza symptoms in adults, but not in asthmatic children." Taking either of the drugs did not reduce hospitalizations or serious complications, but did increase risk of nausea, headaches, and psychiatric symptoms. The CDC responded that their recommendations for antiviral medications "remained unchanged," arguing that observational studies not considered in the Cochrane review supported prescribing neuraminidase inhibitors for high-risk patients with influenza. They provided no rationale for dismissing the results of the randomized trials.

The bottom line for influenza sufferers is that at best, antiviral medications have modest benefits that need to be balanced against potential adverse effects (nausea and vomiting) in deciding whether be treated. Also, existing evidence does not support the CDC's contention that antivirals are more likely to be beneficial in high-risk populations.

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This post first appeared in slightly modified form on the AFP Community Blog.

Health Benefits of Resveratrol: New Plaudits

Joe: My doctor told me to give up drinking, smoking, and fatty foods.

Sam: What will you do?

Joe: I think I’ll give up my doctor.

I try not to get too excited about memory benefits of supplements, because too often the claims are not substantiated by studies that are well controlled and peer reviewed. I now think resveratrol may be one of the few supplements that benefits brain function.

When I wrote my first blog on research on resveratrol benefits for brain function and memory, there were over 2,000 scientific papers.[1]Don't worry; I am only going to tell you about a few studies.

Resveratrol is an active ingredient in red wine. This compound has been credited for explaining why red-wine drinkers in France, who drink more wine than most people, are healthier than would be predicted by their lifestyle of little exercise and eating lots of cheese. The problem is most studies suggest you would have to drink a 100 or more glasses of red wine a day to get much resveratrol effect (and that effect would obviously be negated by a toxic dose of alcohol). An obviously more healthful choice is the highly concentrated pill forms of resveratrol that are now on the market.

Most of the protective biological actions associated with resveratrol have been associated with its scavenger properties for free radicals and the protective effects that it confers on the heart and diabetes. 

One important study comes from a diabetes research group in Brazil recently who reported a beneficial effect of resveratrol on diabetic rats.[2]Resveratrol (in a modest rat dose of 10 and 20 mg per kilogram per day for 30 days) prevented the impairment of memory induced by diabetes. Resveratrol may be protecting neuron terminals that diabetes can damage. An earlier study by another group showed resveratrol improved glucose metabolism and promoted longevity in diabetic mice.

Another benefit of resveratrol is the anti-oxidant property. The brain produces more free-radical damage than other organs, because it burns so much oxygen. Compared with other organs, the brain has especially low levels of antioxidant defense enzymes. 

One recent study has revealed 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) per day for 25 days, beginning four days before the toxin injection.[3]

Another recent study examined effects on working memory in mice fed a resveratrol-supplemented diet for four weeks before being injected with a cytokine to induce inflammation and accelerate aging. Resveratrol significantly reduced memory impairment in the aged group, but not in the young adults[4]. The lack of benefit in young adults was a little misleading, in that there was a "ceiling effect" in that the young adults were not impaired by the cytokine injection.

 The practical issue for us is whether resveratrol will help cognitive function in humans, especially healthy humans. It seems likely because other substances that have strong anti-oxidant properties seem to improve memory capability. Because animal studies have shown promise for resveratrol in preventing or treatment several different conditions associated with aging, several human clinical trials have been initiated.[5]

 An impressive new study of older humans, male and female, has just been reported.[6]Twenty-three healthy, but overweight people completed 6 months of daily resveratrol intake (200 mg ― the commercial brand I take has 300 mg/capsule). A paired control group got placebo pills. A double-blind design assured that neither the subjects nor the experimenters knew which individuals were in each group during data processing. Memory tests of word recall revealed significant improvement in the resveratrol group. Resveratrol also increased brain-scan measures of functional connectivity, which identified linked neural activity between the hippocampus and several areas of cerebral cortex.

Because others had shown that resveratrol increased insulin sensitivity in humans, these authors examine several markers important to diabetes. Resveratrol decreased the standing levels of sugar-bound hemoglobin, a standard marker for glucose control.  

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 much good. Because of the scientifically documented benefits of resveratrol, highly concentrated supplements are now on the market (I have been taking it for a couple of years). 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 high doses of resveratrol are toxic.

---

[1] http://thankyoubrain.blogspot.com/2010/04/resveratrol-red-wine-magic-chemical.htmlApril 4, 2010.

[2] 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.

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

[4] 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

[5]Smoliga, J. M. et al. (2011). Resveratrol and health – a comprehensive review of human clinical trials.  Mol. Nutrition Food Res. 55: 1129-1141

[6] Witte, A. V., et al. (2014) Effects of resveratrol on memory performance, hippocampal functional connectivity, and glucose metabolism in healthy older adults. J. Neuroscience. 34 23): 7862-7870.

"Memory Medic's latest book is for seniors (Improve Your Memory for a Healthy Brain. Memory Is the Canary in Your Brain's Coal Mine," available in inexpensive e-book format at https://www.smashwords.com/books/view/496252.  See also his recent book, "Mental Biology. The New Science of How the Brain and Mind Relate" (Prometheus).

The future of medicine is low-tech and high-touch

A student told me about his experience at TEDMED, the future-oriented medical conference that bills itself as "a celebration of human achievement and the power of connecting the unconnected in creative ways to change our world in health and medicine." He recounted how one speaker showed off the Remote Presence Virtual + Independent Telemedicine Assistant, which news outlets quickly dubbed the "Robo-Doc." This high-priced gadget is designed to provide remote medical services to patients who wouldn't otherwise be able to see real-life doctors, but my student told me that the presentation didn't talk about that much. Instead, he felt, the speaker's message seemed to be: "Robots are cool, so let's make more of them."

Along similar lines, a blog post on the smartphone physical described how a team led by an enterprising Johns Hopkins University medical student created a virtual "checkup" from a combination of smartphone-powered devices. These devices measure standard physical examination parameters such as body mass index, blood pressure, and visual acuity; and less routine tests such as oxygen saturation, electrocardiography, lung function testing, and carotid artery visualization. In addition to collecting far more data than the traditional checkup, the smartphone physical touts the advantage of using devices that are "smaller and less invasive" - no more "fumbling" to take a patient's blood pressure, for example. One commenter gushed, "Getting a smart phone physical was so fun. I got an EKG and an ultrasound of my carotids in under three minutes." So what's not to like?

I'm hardly a Luddite when it comes to adopting the latest in medical technologies, including electronic health records and smartphone apps. But I think it's worth asking how likely it is that high-tech innovations such as robo-docs and smartphone physicals will actually improve patients' health outcomes. For the latter, the answer is not likely at all. A comprehensive review of the evidence on traditional checkups in adults found that they increase the number of diagnoses per patient, but have no effects on hospitalization, disability, worry, absence from work, morbidity, or mortality. Based on other systematic reviews, the U.S. Preventive Services Task Force recommends against doing EKGs, spirometry, or carotid artery ultrasound in healthy adults because the harms of these screening tests outweigh any benefits. False positive results on that 3-minute EKG and ultrasound may lead to an unstoppable cascade of costly cardiovascular stress testing and invasive coronary or carotid angiograms, which can cause serious adverse effects.

If you really want to see the future of medicine, skip TEDMED and head over to Camden, New Jersey, where a family physician named Jeffrey Brenner showed that providing intensive primary care to patients with the most complex illnesses dramatically improved disease outcomes, quality of life, and health care costs. Then hit the road for Lancaster, Pennsylvania, where a similar program empowers "super-utilizer" patients to take control of their health care by providing them with comprehensive, multi-disciplinary case management and social support. On your way, stop by Health Quality Partners in Doylestown, PA, which has improved outcomes and reduced hospitalizations and costs for the sickest Medicare patients through the revolutionary innovation of - wait for it - regular nurse home visits. Here's what Dr. Brenner told Washington Post Wonkblog columnist Ezra Klein when asked what he thought of the Doylestown program:

"There is a bias in medicine against talking to people and for cutting, scanning and chopping into them. If this was a pill or or a machine with these results it would be front-page news in the Wall Street Journal. If we could get these results for your grandmother, you’d say, ‘Of course I want that.’ But then you’d say, what are the risks? Does she need to have chemotherapy? Does she need to be put in a scanner? Is it a surgery? And you’d say, no, you just have to have a nurse come visit her every week."

Later in the column, Klein reflects:

We’ve been conditioned by “Grey’s Anatomy” and hospital rooms to believe that saving lives is a complicated, heroic business. And it is — after people get very sick. But keeping them from getting very sick doesn’t necessarily require the discovery of new molecules. It requires someone who has a relationship with them to stop by once a week to see how they’re doing. The problem is, it’s hard to make money off it.

Pop culture and perverse financial incentives inherent in fee-for-service payment reinforce a bias for health care services that are high-tech and low-touch. Yes, robots and smartphones can and will play vital roles in the future of medicine. But if we really want sick patients to have the best chance to get better - and healthy patients to avoid getting sick in the first place - then we should do everything in our power to support low-tech and high-touch interventions too.

Remembering Dr. King

I have a dream that my four little children will one day live in a nation where they will not be judged by the color of their skin, but by the content of their character.

Of all the forms of inequality, injustice in health care is the most shocking and inhuman.

- Martin Luther King, Jr.

Screening for hepatitis C and lung cancer: proceed with caution

Most of my patients don't know (or if they know, don't particularly care) that I blog, but after practicing for nearly three years at the same Washington, DC practice, I am starting to see a few who specifically chose me to be their doctor because of something I wrote in Common Sense Family Doctor or my health care philosophy of "conservative medicine." It isn't that I am averse to doing screening tests; for example, I still order PSA tests for men and mammograms for women in their 40s, provided that they have been informed of the likely harms as well as the possible benefits. What I can't abide are physicians who bully patients into having these tests, or in the case of prostate cancer screening, order the test without even bothering to tell them.

Speaking of screening tests, my first video commentary for Medscape Family Medicine addressed the key issues that primary care physicians will need to review with patients eligible for CT lung cancer screening. Recognizing that the decision to screen or not screen will be a close call for many, the Centers for Medicare & Medicaid Services plans to pay physicians to have a discussion about pros and cons. Although I am concerned that these discussions may not happen, I hope that my commentary makes a difference. Non-clinicians who don't have access to Medscape can read about the issues in one of my previous blog posts.

This week also saw the publication of the analysis, "Is widespread screening for hepatitis C justified?" that I co-authored in BMJ with Ron Koretz, John Ioannidis, and Jeanne Lenzer. In this paper, we argued that the rush to expand screening to all persons born between 1945 and 1965 (the "Baby Boomer" generation) regardless of health status or risk factors could do more harm than good because 80 percent of people with chronic hepatitis C do not develop liver complications and, therefore, cannot benefit from treatment; and the surrogate marker ("sustained viral response" after 12 weeks) that persuaded the U.S. Food and Drug Administration to approve the fantastically expensive new drugs may correlate imperfectly with the health outcomes that patients really care about:

Given the uncertainty about the validity of the surrogate markers, the lack of evidence regarding clinical outcomes of treatment or of screening strategies, and the adverse events caused by the newer regimens, screening may be premature. ... Given the converging recommendations from major organisations for widespread screening, the pressure on practitioners to adopt this policy is mounting. We have a limited window of opportunity to collect appropriate evidence on whether this is a good idea. Until then, physicians should not be pressured to enforce birth cohort screening strategies out of enthusiasm for new treatments that have not yet been shown to cause long term clinical improvement.

For additional context, or if you prefer listening to reading, Jeanne and I recorded a 15-minute podcast to accompany the article which nicely summarized these arguments.

Can treating mild hypertension be too much medicine?

As part of a plan to improve our practice's quality of care for patients with high blood pressure, my office's nurse announces at every morning huddle which patients on that day's schedule had a blood pressure measurement of greater than 140/90 at their last visit. Most of these patients have measurements consistent with mild hypertension (systolic blood pressure less than 160 mm Hg and/or diastolic blood pressure less than 100 mm Hg). However, a previous AFP Community Blog post pointed out that the few randomized trials of anti-hypertensive medications in this population did not show improvements in cardiovascular outcomes or mortality.

In fact, some have gone as far to suggest that the identification and treatment of mild hypertension in persons at low cardiovascular risk may be "too much medicine," given the poor accuracy of office blood pressure measurements and that these patients typically receive drugs (and their accompanying side effects) rather than lifestyle change counseling. Last year's JNC 8 Guideline for the Management of High Blood Pressure in Adults added fuel to this controversy by acknowledging that no randomized trial evidence supports any systolic blood pressure treatment threshold in adults younger than 60 years, and recommending that adults 60 years and older receive medication only if their blood pressure is higher than 150/90.

In the first of a series of AFP editorials about overscreening, overdiagnosis, and overtreatment, Drs. Mark Ebell and Jessica Herzstein highlighted several examples of screening that does not improve patient-oriented outcomes: too-short intervals between screening colonoscopies; Pap smears in women after a hysterectomy for benign disease; and mammography in older women with dementia. Does looking for hypertension in adults without cardiovascular risk factors fall into this category as well?

A new meta-analysis published in the Annals of Internal Medicine could tip the scales in favor of medicating adults with mild hypertension. Combining individual-patient data from a collaboration of blood pressure treatment trials with that from a previous Cochrane review, Dr. Johan Sundstrom and colleagues concluded that pharmacotherapy for mild hypertension reduced the relative risk of strokes, cardiovascular deaths, and total deaths by 22 to 28 percent after 5 years. (They estimated, however, that absolute risk reductions in contemporary primary care populations would be a modest 0.6 to 1.2 percent, or a number needed to treat of 83 to 167.)

Key take-home points are that the absolute benefits of treating otherwise healthy persons with mild hypertension are relatively small; lifestyle modification should generally precede medication; and blood pressure measurement should be performed and repeated carefully to ensure accurate identification of hypertensive patients. In a draft recommendation statement, the U.S. Preventive Services Task Force recently advised routine home blood pressure monitoring to confirm new hypertension diagnoses, which should hopefully limit overdiagnosis and overtreatment.

**

This post first appeared on the AFP Community Blog.

Creative imagination

There is a constant need of imagination. Synthetic imagination is the manipulation of effects. Creative imagination is causal that produce effects.

Creative imagination is more than mere memory. It takes the elements of the past as reproduced by memory and rearranges them.

Creative imagination plays a vital role in human daily life. Creative imagination is not inborn trait and it can be acquired with constant exercise.

The creative imagination galvanizing the mind propels it on a quest that transforms the already being constituted reality. It activates the minds radius of propensities and a fulgurating variation of virtualities.

Creative imagination is an essential aspect for achieving success. One needs to practice it incessantly in the same way they do anything else. Imagination can be sharpened largely if one practices creative thinking.
Creative imagination

Why every screening test is a gamble

I'm in Las Vegas for the first time in 15 years to attend the International Consumer Electronics Show, and earlier today participated in a panel of "early-adopter" family physicians discussing our perspectives on consumer (patient) health technology such as apps and wearable health data collection devices. I'm staying at one of Vegas's many combination hotel and casinos, with a layout designed to funnel guests and other visitors through the gaming floor to get practically anywhere. While walking past a row of pulsating slot machines in the lobby this morning, I remembered the title of a terrific New York Times editorial I read a few years ago, "You Have to Gamble On Your Health."

Courtesy of www.lasvegas.com

In this editorial, Dr. H. Gilbert Welch (whom I've lauded before for his work on the subject of overdiagnosis) explained why even though most people who receive screening tests for cancer think that they are playing it safe, every test has tradeoffs. Just as a gambler rarely hits the jackpot in Vegas, a patient who undergoes cancer screening is rarely the lucky one whose life is extended from the test, and much more likely to figuratively lose his or her shirt. Common harms of screening include false positive results, risks associated with subsequent diagnostic procedures, and possible unnecessary treatment (and associated side effects) for "cancer" that looks dangerous under the microscope but is actually destined to never cause health problems.

Courtesy of www.lasvegas.com

The good news is that for a few very well-studied screening tests such as mammography, an informed patient can assess the odds of all of these outcomes and decide whether screening is a better choice for her than no screening. A mammography screening decision aid by Dr. Jill Jin that appeared in last month's JAMA did a great job of illustrating these tradeoffs, and may help to explain why a prominent health journalist recently announced that she had decided to forego mammography because she believed that "the numbers are in my favor."

Yes, every screening test is a gamble, but I give credit to my fellow physicians for providing increasingly sophisticated support for these tough decisions that you'd never get in Vegas.

Happy Thoughts Can Make You More Competent

“Life, liberty, and the pursuit of happiness:” some people might argue that the U.S. Constitution endorses hedonism, and indeed many politicians want to ignore or get rid of the Constitution, but not necessarily because of hedonism. We should not be dismissive about encouraging people to pursue happiness. Happiness can be good for your brain. Depression is surely bad for your brain.

Positive mood states promote more effective thinking and problem solving. A recent scholarly report[1] reviews the literature demonstrating that positive mood broadens the scope of attentiveness, enhances semantic associations over a wider range, improves task shifting, and improves problem-solving capability. The review also documents the changes in brain activation patterns induced by positive mood in subjects while solving problems. Especially important is the dopamine signaling in the prefrontal cortex.

Published studies reveal that a variety of techniques are used to momentarily manipulate mood. These have included making subjects temporarily happy or sad by asking subjects to recall emotionally corresponding past experiences or to view film clips or hear words that trigger happy or sad feelings,

The effect of happiness on broadened attentiveness arises because the brain has better cognitive flexibility and executive control, which in turn makes it easier to be more flexible and creative. Happy problem solvers are better able to select and act upon useful solutions that otherwise never consciously surface. Happiness reduces perseverative tendencies for errant problem-solving strategies. The broadened attentiveness, for example, allows people to attend to more stimuli, both in external visual space and in internal semantic space, which in turn enables more holistic processing. For example, in one cited study, experimenters manipulated subjects’ momentary mood and then measured performance on a task involving matching of visual objects based on their global versus local shapes. Happy moods yielded better global matching.

Other experiments report broader word association performance when subjects are manipulated to be happier. For example, subjects in a neutral mood would typically associate the word “pen” as a writing tool and would associate it with words like pencil or paper. But positive mood subjects would think also of pen as an enclosure and associate it with words like barn or pigs. This effect has been demonstrated with practical effect in physicians, who, when in a happy mood, thought of more disease possibilities in making a differential diagnosis.
The review authors reported their own experiment on beneficial happy mood effects on insightfulness, using a task in which subjects were given three words and asked to think of a fourth word that could be combined into a compound word or phrase. For example, an insightful response to “tooth, potato, and heart” might be “sweet tooth, sweet potato, and sweetheart.” Generating such insight typically requires one to suppress dominant “knee jerk” responses such as associating tooth with pain and recognize that pain does not fit potato while at the same time becoming capable of switching to non-dominant alternatives.

Other cited experiments showed that happy mood improved performance on “Duncker’s candle task.”  Here, subjects are given a box of tacks, a candle, and a book of matches, and are asked to attach a candle to the wall in a way that will burn without dripping wax on the floor. Subjects in a happy mood were more able to realize that the box could be a platform for the candle when the box is tacked to the wall.  

Such effects of happy moods seem to arise from increased neural activity in the prefrontal cortex and cingulate cortex, areas that numerous prior studies have demonstrated as crucial parts of the brain’s executive control network. Similar effects have been observed in EEG studies. Other research suggests that the happiness effect is mediated by increased release of dopamine in the cortex that serves to up-regulate executive control.
The review authors described a meta-analysis of 49 positive-psychology manipulation studies showing that momentary happiness is readily manipulated by such strategies as deliberate optimistic thinking, increased attention to and memory of happy experiences, practicing mindfulness and acceptance, and increasing socialization. The effect occurs in most normal people and even in people with depression, anxiety, and schizophrenia. Biofeedback training, where subjects monitor their own fMRI scans or EEGs, might be an even more effective way for people to train themselves to be happier.

The main point is that people can be as happy as they choose to be.

For more on how positive mood influences memory ability, see my new book, Memory Power 101 (http://skyhorsepublishing.com ). Memory Medic's latest book explores the biology of mind. See "Mental Biology. The New Science of How the Brain and Mind Relate" (Prometheus).

[1] Subramaniam, K. and Vinogradov, S. (2013). Improving the neural mechanisms of cognition through the pursuit of happiness. Frontiers in Human Neuroscience. 7 August. Doi: 10.3389/fnhum.2013.00452