Chewing Gum May Help Reduce Stress According To New Research

01 Sep 2008

Study presented at the 2008 10th International Congress of Behavioral Medicine

WHAT: "An investigation into the effects of gum chewing on mood and cortisol levels during psychological stress," presented at the 2008 10th International Congress of Behavioral Medicine, found that chewing gum helped relieve anxiety, improve alertness and reduce stress among individuals in a laboratory setting.* The study examined whether chewing gum is capable of reducing induced anxiety and/or acute psychological stress while participants performed a battery of 'multi-tasking' activities. The use of chewing gum was associated with higher alertness, reduced anxiety and stress, and improvement in overall performance on multi-tasking activities.

WHO: Andrew Scholey, Ph.D., professor of Behavioral and Brain Sciences, Swinburne University in Melbourne, Australia led the research study and can discuss the effect of chewing gum on stress relief and focus and concentration.

Gilbert Leveille, Ph.D., executive director, Wrigley Science Institute, will also be available to discuss research on the benefits of chewing gum related to stress relief and alertness and concentration in addition to other areas including weight management and oral health.

WHEN: Study was presented orally on Saturday, August 30 at Rissho University in Tokyo, Japan at the 10th International Congress of Behavioral Medicine.

STUDY BACKGROUND:

In the 40-person study of gum chewers averaging an age of 22 years old, performed on the Defined Intensity Stressor Simulation (DISS), a multi-tasking platform which reliably induces stress and also includes performance measures, while chewing and not chewing gum. Anxiety, alertness and stress levels were measured before and after participants completed the DISS.

• Relieved Anxiety: When chewing gum, participants reported lower levels of anxiety.
  Gum chewers showed a reduction in anxiety as compared to non-gum chewers by nearly 17 percent during mild stress and nearly 10 percent in moderate stress.
  
  
• Increased Alertness: Participants experienced greater levels of alertness when they chewed gum.
  Gum chewers showed improvement in alertness over non-gum chewers by nearly 19 percent during mild stress and 8 percent in moderate stress.
  
  
• Reduced Stress: Stress levels were lower in participants who chewed gum.
  Levels of salivary cortisol (a physiological stress marker) in gum chewers were lower than those of non-gum chewers by 16 percent during mild stress and nearly 12 percent in moderate stress.
  
  
• Improved Performance: Chewing gum resulted in a significant improvement in overall performance on multi-tasking activities. Both gum-chewers and non-chewers showed improvement from their baseline scores; however, chewing gum improved mean performance scores over non-gum chewers by 67 percent during moderate stress and 109 percent in mild stress.

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Article adapted by Medical News Today from original press release.
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WRIGLEY SCIENCE INSTITUTE:

Wrigley is committed to advancing and sharing scientific research that explores the benefits of chewing gum. The Chicago-based Wrigley Science Institute works with independent researchers at leading institutions to learn more about the potential health and wellness benefits of chewing gum. The Wrigley Science Institute's current work is focused on four key scientific areas: how gum can help reduce situational stress; help manage weight; help increase focus, alertness and concentration; and improve oral health.

*Scholey, Andrew. An investigation into the effects of gum chewing on mood and cortisol levels during psychological stress. 10th International Congress of Behavioral Medicine. Tokyo, Japan. August 2008.

Another Kind of Addict

What exactly is sex addiction, and how are those who suffer from the disorder, like actor David Duchovny, treated?

Susanna Schrobsdorff

Newsweek Web Exclusive

Updated: 3:58 PM ET Sep 2, 2008

The term "sex addict" has been used as a punch line on television so often that it's hard to believe that it can actually be a serious addiction, like alcoholism. So when "X Files" star, David Duchovny, announced last week that he was entering rehab for treatment of a sexual addiction, it almost seemed like a fictional plotline for the Showtime series "Californication," on which Duchovny plays a sex-obsessed single dad. But for those affected, the ramifications of a sexual addiction are all too real, often leaving marriages, careers and bank accounts in ruins. For celebrities who are contending with sexual problems, there's often the added humiliation of having their difficulties made public. This summer, the tabloids were filled with lurid stories of out-of-control spending on Internet porn by Peter Cook, husband of model Christie Brinkley. And of course, in Hollywood, tales of actors risking their reputations by picking up street prostitutes are too numerous to mention.

What exactly constitutes a sexual addiction? It's generally described as obsessive sexually related behavior that dominates the addict's life. The compulsive behavior can range from obsessive use of pornography or promiscuity, to use of prostitutes or even sexual violence. Still, the notion that people can be clinically addicted to sex is controversial. Sex addiction, is not recognized by the American Psychological Association as a diagnosable disorder; and when news breaks of yet another philandering celebrity or politician, the public is likely to assume the person is suffering from an extreme case of caddishness rather than a bona fide illness. To learn more about how sexual addictions are treated and diagnosed, NEWSWEEK's Susanna Schrobsdorff spoke to Jill W. Bley, a clinical psychologist and sex therapist in Cincinnati. Excerpts:

NEWSWEEK: The term "sex addiction" isn't universally accepted among psychologists, is it?
Jill Bley: It's been controversial in our field. There's one group of people who have researched this who say that label can only be applied when there's a substance involved. They wouldn't talk about a gambling addiction; they would talk about compulsive gambling behavior. Those of us who do the clinical work, we don't care what you call it. We look at the behavior. I may tell someone they have an obsessive-compulsive sexual need. The only time the label makes a difference is if you go to court or justify something with an insurance company—then you call it obsessive-compulsive behavior.

Some people see the sex-addict label as just an excuse for a guy who cheats. What's the difference between someone who needs psychological help and someone who is just a jerk?
Some are jerks. But there's a huge difference between someone who's cheating and an addict. A person who has a sexual addiction is engaging in obsessive-compulsive sexual behavior, which causes severe stress to the addicted individual and their families, and over which they do not have control.

The statistics say that more men get help for sex addiction than women. Is there a difference between male and female sex addicts?
Male and female sex addicts are pretty much the same. Women tend to get into love addictions more, though men sometimes do too. [A love addiction] may look like a sex addiction, but what they're really in it for is the high of being adored, getting attention. Women may feel they are only valued for their bodies, so they use their bodies to attract attention or love.

Are there men who say urges are normal male biology and that they can't help pursuing sex all the time?
Sometimes it is the thrill of the chase, which is normal, but not if the pursuit becomes compulsive. This one person I work with, he had about 40 women that he was involved with. He had four cell phones. He'd give different women the numbers so he could figure out which woman was calling and keep them separate. He would tell me all the time, "I can't help it. Women are hitting on me wherever I go; I get on the plane and the flight attendant starts coming on to me." This man even said that my secretary was hitting on him when he came in for a therapy appointment, and I can say definitely that she wasn't.

Are these people unusually egotistical?
There's a lot of narcissism and arrogance with people like this. In therapy you have to help them confront that. They feel like the world revolves around them. But that's really a shield, a protection for an ego that was damaged as they grew up.

Does the kind of guy you were talking about succeed with women, if everyone isn't actually hitting on them as they think?
These kinds of men do get women because they're smooth talkers and they can be very charming. They make women feel like they're the only one, even when she's not. Secrecy is very important—that's a big part of the thrill for them.

That risk-taking thrill sounds like some of the politicians who have been caught up in sex scandals.
Yes. People wonder why [those sorts of] men … would risk everything. What it is, is that they get addicted to the adrenaline flow. The riskier it gets, the more adrenaline they get. Like all addictions, the more they get, the more they need. It may seem stupid from the outside, but that's not what someone is thinking when they're caught up in the addiction cycle. It starts with a preoccupation—they're thinking and thinking of whatever their sexual compulsion is. Then they move to the next level of the cycle, which we call ritualization. It's whatever activity they do that they think will help them find what they're addicted to. Once they get to that second stage, they're probably going to go all the way. They'll get in the car and drive toward a strip club or the street where they pick up prostitutes. Afterwards they may be very ashamed. But eventually the cycle will start all over again.

What makes them seek treatment?
Usually, it's because they get caught. Or the addiction is making it impossible for them to function.

How do you help them stop that cycle of addiction?
We try to help them stop when they are in the thinking-about-it stage, the preoccupation stage. That's when we say, "You have to call your sponsor." The other thing is that there have to be no secrets, not from their sponsor and not from their significant other. It's part of the intimacy work they have to do with their partner.

That sounds like Alcoholics Anonymous.
The treatment is somewhat different from alcoholism or other addiction treatments, yet very much the same. The first step is to acknowledge the problem. Then, if they work the 12 steps to recovery, they will go to 90 [group treatment] meetings in 90 days. It's important that they get a sponsor, too. That's the person you call for the purpose of helping you not act out sexually, and also help[ing] you work through the stresses and anxiety that lead to acting out sexually. Sometimes treatment means checking into a rehab center so [patients] can get out of their normal environment and habits.

But you can't give up sex forever the same way you can give up alcohol, can you?
When they start the process I will ask them for six weeks of total abstinence. Not even masturbation. It's really hard for the addicts, but you can't do anything till they get sober and abstinent. We have their partner agree. During that six weeks, the anxieties that led to the sexual acting out usually become very apparent to the therapist and the partner. Those anxieties are what you want to work on. Then after the six weeks you have them work on having all their sexual behavior directed toward their partner.

And after that?
A huge part of the treatment is to look for the trauma in the person's life that is creating the stress. You want to get at the cause and reprocess what has happened to them. Most of them have been victims of some kind of emotional abuse as children. That means having a parent who derides you, constantly criticizes you or calls you names. And 81 percent of those who come for treatment have been sexually abused, 73 percent physically abused. Most of them deny their abuse history. Or they might not remember it until they've been in therapy for a while.

Does insurance cover treatment for sex addictions?
No, not usually. But patients are often able to work out a payment plan.

High-Aptitude Minds: The Neurological Roots of Genius

Researchers are finding clues to the basis of brilliance in the brain

By Christian Hoppe and Jelena Stojanovic

Within hours of his demise in 1955, Albert Einstein’s brain was salvaged, sliced into 240 pieces and stored in jars for safekeeping. Since then, researchers have weighed, measured and otherwise inspected these biological specimens of genius in hopes of uncovering clues to Einstein’s spectacular intellect.

Their cerebral explorations are part of a century-long effort to uncover the neural basis of high intelligence or, in children, giftedness. Traditionally, 2 to 5 percent of kids qualify as gifted, with the top 2 percent scoring above 130 on an intelligence quotient (IQ) test. (The statistical average is 100. See the box on the opposite page.) A high IQ increases the probability of success in various academic areas. Children who are good at reading, writing or math also tend to be facile at the other two areas and to grow into adults who are skilled at diverse intellectual tasks [see “Solving the IQ puzzel,” by James R. Flynn; Scientific American Mind, October/November 2007].

Most studies show that smarter brains are typically bigger—at least in certain locations. Part of Einstein’s parietal lobe (at the top of the head, behind the ears) was 15 percent wider than the same region was in 35 men of normal cognitive ability, according to a 1999 study by researchers at McMaster University in Ontario. This area is thought to be critical for visual and mathematical thinking. It is also within the constellation of brain regions fingered as important for superior cognition. These neural territories include parts of the parietal and frontal lobes as well as a structure called the anterior cingulate.

But the functional consequences of such enlargement are controversial. In 1883 English anthropologist and polymath Sir Francis Galton dubbed intelligence an inherited feature of an efficiently functioning central nervous system. Since then, neuroscientists have garnered support for this efficiency hypothesis using modern neuroimaging techniques. They found that the brains of brighter people use less energy to solve certain prob­lems than those of people with lower aptitudes do.

In other cases, scientists have observed higher neuronal power consumption in individuals with superior mental capacities. Musical prodigies may also sport an unusually energetic brain [see box on page 67]. That flurry of activity may occur when a task is unusually challenging, some researchers speculate, whereas a gifted mind might be more efficient only when it is pondering a relatively painless puzzle.

Despite the quest to unravel the roots of high IQ, researchers say that people often overestimate the significance of intellectual ability [see “Coaching the Gifted Child,” by Christian Fischer]. Studies show that practice and perseverance contribute more to accomplishment than being smart does.

Size Matters
In humans, brain size correlates, albeit somewhat weakly, with intelligence, at least when researchers control for a person’s sex (male brains are bigger) and age (older brains are smaller). Many modern studies have linked a larger brain, as measured by magnetic resonance imaging, to higher intellect, with total brain volume accounting for about 16 percent of the variance in IQ. But, as Einstein’s brain illustrates, the size of some brain areas may matter for intelligence much more than that of others does.

In 2004 psychologist Richard J. Haier of the University of California, Irvine, and his colleagues reported evidence to support the notion that discrete brain regions mediate scholarly aptitude. Studying the brains of 47 adults, Haier’s team found an association between the amount of gray matter (tissue containing the cell bodies of neurons) and higher IQ in 10 discrete regions, including three in the frontal lobe and two in the parietal lobe just behind it. Other scientists have also seen more white matter, which is made up of nerve axons (or fibers), in these same regions among people with higher IQs. The results point to a widely distributed—but discrete—neural basis of intelligence.

The neural hubs of general intelligence may change with age. Among the younger adults in Haier’s study—his subjects ranged in age from 18 to 84—IQ correlated with the size of brain regions near a central structure called the cingulate, which participates in various cognitive and emotional tasks. That result jibed with the findings, published a year earlier, of pediatric neurologist Marko Wilke, then at Cincinnati Children’s Hospital Medical Center, and his colleagues. In its survey of 146 children ages five to 18 with a range of IQs, the Cincinnati group discovered a strong connection between IQ and gray matter volume in the cingulate but not in any other brain structure the researchers examined.

Scientists have identified other shifting neural patterns that could signal high IQ. In a 2006 study child psychiatrist Philip Shaw of the National Institute of Mental Health and his colleagues scanned the brains of 307 children of varying intelligence multiple times to determine the thickness of their cerebral cortex, the brain’s exterior part. They discovered that academic prodigies younger than eight had an unusually thin cerebral cortex, which then thickened rapidly so that by late childhood it was chunkier than that of less clever kids. Consistent with other studies, that pattern was particularly pronounced in the frontal brain regions that govern rational thought processes.

The brain structures responsible for high IQ may vary by sex as well as by age. A recent study by Haier, for example, suggests that men and women achieve similar results on IQ tests with the aid of different brain regions. Thus, more than one type of brain architecture may underlie high aptitude.

Low Effort Required
Meanwhile researchers are debating the functional consequences of these structural findings. Over the years brain scientists have garnered evidence supporting the idea that high intelligence stems from faster information processing in the brain. Underlying such speed, some psychologists argue, is unusually efficient neural circuitry in the brains of gifted individuals.

Experimental psychologist Werner Krause, formerly at the University of Jena in Germany, for example, has proposed that the highly gifted solve puzzles more elegantly than other people do: they rapidly identify the key information in them and the best way to solve them. Such people thereby make optimal use of the brain’s limited working memory, the short-term buffer that holds items just long enough for the mind to process them.

Starting in the late 1980s, Haier and his colleagues have gathered data that buttress this so-called efficiency hypothesis. The researchers used positron-emission tomography, which measures glucose metabolism of cells, to scan the brains of eight young men while they performed a nonverbal abstract reasoning task for half an hour. They found that the better an individual’s performance on the task, the lower the metabolic rate in widespread areas of the brain, supporting the notion that efficient neural processing may underlie brilliance. And in the 1990s the same group observed the flip side of this phenomenon: higher glucose metabolism in the brains of a small group of subjects who had below-average IQs, suggesting that slower minds operate less economically.

More recently, in 2004 psychologist Aljoscha Neubauer of the University of Graz in Austria and his colleagues linked aptitude to diminished cortical activity after learning. The researchers used electroencephalography (EEG), a technique that detects electrical brain activity at precise time points using an array of electrodes affixed to the scalp, to monitor the brains of 27 individuals while they took two reasoning tests, one of them given before test-related training and the other after it. During the second test, frontal brain regions—many of which are involved in higher-­order cognitive skills—were less active in the more intelligent individuals than in the less astute subjects. In fact, the higher a subject’s mental ability, the bigger the dip in cortical activation between the pretraining and posttraining tests, suggesting that the brains of brighter individuals streamline the processing of new information faster than those of their less intelligent counterparts do.

The cerebrums of smart kids may also be more efficient at rest, according to a 2006 study by psychologist Joel Alexander of Western Oregon University and his colleagues. Using EEG, Alexander’s team found that resting eight- to 12-hertz alpha brain waves were significantly more powerful in 30 adolescents of average ability than they were in 30 gifted adolescents, whose alpha-wave signal resembled those of older, college-age students. The results suggest that gifted kids’ brains use relatively little energy while idle and in this respect resemble more developmentally advanced human brains.

Some researchers speculate that greater energy efficiency in the brains of gifted individuals could arise from increased gray matter, which might provide more resources for data processing, lessening the strain on the brain. But others, such as economist Edward Miller, formerly of the University of New Orleans, have proposed that the efficiency boost could also result from thicker myelin, the substance that insulates nerves and ensures rapid conduction of nerve signals. No one knows if the brains of the quick-witted generally contain more myelin, although Einstein’s might have. Scientists probing Einstein’s brain in the 1980s discovered an unusual number of glia, the cells that make up myelin, relative to neurons in one area of his parietal cortex.

Hardworking Minds
And yet gifted brains are not always in a state of relative calm. In some situations, they appear to be more energetic, not less, than those of people of more ordinary intellect. What is more, the energy-gobbling brain areas roughly correspond to those boasting more gray matter, suggesting that the gifted may simply be endowed with more brainpower in this intelligence network.

In a 2003 trial psychologist Jeremy Gray, then at Washington University in St. Louis, and his colleagues scanned the brains of 48 individuals using functional MRI, which detects neural activity by tracking the flow of oxygenated blood in brain tissue, while the subjects completed hard tasks that taxed working memory. The researchers saw higher levels of activity in prefrontal and parietal brain regions in the participants who had received high scores on an intelligence test, as compared with low scorers.

In a 2005 study a team led by neuroscientist Michael O’Boyle of Texas Tech University found a similar brain activity pattern in young male math geniuses. The researchers used fMRI to map the brains of mathematically gifted adolescents while they mentally rotated objects to try to match them to a target item. Compared with adolescent boys of average math ability, the brains of the mathematically talented boys were more metabolically active—and that activity was concentrated in the parietal lobes, the frontal cortex and the anterior cingulate.

A year later biologist Kun Ho Lee of Seoul National University in Korea similarly linked elevated activity in a frontoparietal neural network to superior intellect. Lee and his co-workers measured brain activity in 18 gifted adolescents and 18 less intelligent young people while they performed difficult reasoning tasks. These tasks, once again, excited activity in areas of the frontal and parietal lobes, including the anterior cingulate, and this neural commotion was significantly more intense in the gifted individuals’ brains.

No one is sure why some experiments indicate that a bright brain is a hardworking one, whereas others suggest it is one that can afford to relax. Some, such as Haier—who has found higher brain metabolic rates in more astute individuals in some of his studies but not in others—speculate one reason could relate to the difficulty of the tasks. When a problem is very complex, even a gifted person’s brain has to work to solve it. The brain’s relatively high metabolic rate in this instance might reflect greater engagement with the task. If that task was out of reach for someone of average intellect, that person’s brain might be relatively inactive because of an inability to tackle the problem. And yet a bright individual’s brain might nonetheless solve a less difficult problem efficiently and with little effort as compared with someone who has a lower IQ.

Perfection from Practice
Whatever the neurological roots of genius, being brilliant only increases the probability of success; it does not ensure accomplishment in any endeavor. Even for academic achievement, IQ is not as important as self-discipline and a willingness to work hard.

University of Pennsylvania psychologists Angela Duckworth and Martin Seligman examined final grades of 164 eighth-grade students, along with their admission to (or rejection from) a prestigious high school. By such measures, the researchers determined that scholarly success was more than twice as dependent on assessments of self-discipline as on IQ. What is more, they reported in 2005, students with more self-discipline—a willingness to sacrifice short-term pleasure for long-term gain—were more likely than those lacking this skill to improve their grades during the school year. A high IQ, on the other hand, did not predict a climb in grades.

A 2007 study by Neubauer’s team of 90 adult tournament chess players similarly shows that practice and experience are more important to expertise than general intelligence is, although the latter is related to chess-playing ability. Even Einstein’s spectacular success as a mathematician and a physicist cannot be attributed to intellectual prowess alone. His education, dedication to the problem of relativity, willingness to take risks, and support from family and friends probably helped to push him ahead of any contemporaries with comparable cognitive gifts.

B Vitamins, Folic Acid Do Not Reduce Depression Incidence, Severity CME

Medscape Medical News

News Author: Caroline Cassels
CME Author: Désirée Lie, MD, MSEd

August 25, 2008 — Supplementation with B vitamins appears to be no better than placebo in reducing the incidence of depression or depressive symptoms, new research suggests.

A randomized, double-blind, placebo-controlled trial of 299 older men showed treatment with vitamins B12, B6, and folic acid produced no significant change in mood for 2 years.

"We investigated the association between vitamin use and depression in 3 different ways, none of which showed an advantage of B vitamins compared with placebo over 24 months: change in Beck Depression Index [BDI] scores, incidence of clinically significant depressive symptoms, and remission of depression," the authors write.

With first author Andrew H. Ford, MBBS, from South Metropolitan Health Service, in Perth, Australia, the study is published in the August issue of the Journal of Clinical Psychiatry.

Previous research has linked lower concentrations of B vitamins and folate to depression. However, many of these reports have been observational and or confounded by the fact that participants were receiving antidepressants.

Prospective Design

The purpose of the current study was to prospectively determine whether treatment with B vitamins during an extended period reduced the onset of clinically depressive symptoms in a cohort of men aged 75 years and older.

For the study, investigators recruited a random sample of 299 subjects who were participants in a large population-based study of abdominal aortic aneurysm screening.

All subjects were being treated for or had a history of hypertension. Individuals were excluded from the study if they had a BDI score of 18 or higher and significant cognitive impairment, as determined by a Mini-Mental State Examination (MMSE) score of less than 24. In addition, individuals who were already taking B vitamins were excluded from the study, which was conducted from June 2001 to June 2004.

Participants were randomized to receive a single oral capsule containing 400 µg B12, 2 mg folic acid, and 25 mg B6 or an identical-looking placebo capsule. Study subjects were told to consume 1 capsule every morning for 2 years.

Study subjects and investigators were blinded to group membership until the last follow-up assessment was completed.

The study's primary outcome was changes in BDI scores during the study period. The researchers also examined the proportion of individuals who were free of clinically significant depressive symptoms at baseline, but they became depressed during the trial.

A total of 149 and 150 subjects were in the placebo and active-treatment groups, respectively. With a 19.4% dropout rate, the final analysis was based on the 241 who completed the 2-year trial.

Role as Adjunctive Therapy?

The study revealed that participants in the active-treatment group were 24% more likely to remain free of depression during the trial, but the difference between the groups was not significant.

Among 23 men — 12 in the vitamin group and 11 in the placebo cohort — who had mild to moderate depression, there was no difference between the 2 groups after 24 months of treatment.

Investigators also found that participants in the active-treatment group had increased blood levels of B12 and folate and reduced levels of plasma homocysteine. They also found that these blood levels were similar in men with and without depression, a finding that suggests the potential link between low vitamin B levels, high homocysteine, and depression is not strong.

"It remains to be determined whether vitamin supplementation would be an effective adjunctive antidepressant treatment for people with severe depression, and if women would benefit more than men from this therapeutic approach," they write.

The authors have disclosed no relevant financial relationships.

J Clin Psychiatry. 2008;69:1203-1209.
Learning Objectives for This Educational Activity
Upon completion of this activity, participants will be able to:

1. Describe the effect of vitamin B supplementation on symptoms of depression in elderly men.
2. Describe the effect of vitamin B supplementation on the likelihood of new depressive symptoms in elderly men.

Clinical Context

Depression is a leading cause of disability, affecting 2% to 5% of the adult population. Some preliminary evidence suggests that deficiencies of vitamin B contribute to the onset and maintenance of depression and its symptoms through an effect on the risk for cerebrovascular disease, and cross-sectional studies suggest that patients with depression may have lower serum levels of B vitamins compared with adults without depression.

This is a 2-year, double-blind, randomized clinical trial conducted in elderly men who were originally recruited as part of a population-based study of abdominal aneurysm screening. The study assesses the role of vitamin B supplementation on depression and new onset depressive symptoms.
Study Highlights

* Included were 299 men aged 75 years or older with a history of hypertension from a pool of 12,203 men in the original abdominal aneurysm screening study in 1 city in Australia.
* The men had been identified from the electronic electoral roll.
* Excluded were those with a BDI score of 18 or higher or significant cognitive impairment defined as MMSE score lower than 24, those with serious illness, and those who were taking vitamin B supplements.
* 150 were randomized to treatment consisting of 1 capsule of 400 μg B12, 2 mg folic acid, and 25 mg B6 daily, previously shown to be effective in lowering homocysteine levels; and 149 were randomized to identical-looking placebo 1 capsule daily for 2 years.
* Assessments occurred at baseline, 6, 12, 18, and 24 months.
* MMSE was used to assess cognitive function.
* Hazardous alcohol intake was defined as more than 4 standard drinks at least 4 times weekly or more than 6 drinks on any single day.
* Primary outcome was BDI score consisting of 21 questions scoring from 0 to 3 each, with scores ranging from 0 to 63.
* BDI scores were categorized in 4 groups of “no to minimal depression,” “mild to moderate depression,” “moderate to severe depression,” and “severe depression.”
* Other outcomes were increase in BDI scores, scores greater than 9 (suggestive of at least mild depressive symptoms), and new onset depressive symptoms.
* Fasting samples were taken for serum B12, total plasma homocysteine, and red cell folate levels.
* Mean age was 79 years, and 8.7% to 13.4% were considered to ingest harmful levels of alcohol.
* The dropout rate was 19.4% with the final analysis based on 241 participants.
* There was no difference between the 2 groups in BDI scores over time or change of scores in each group over time.
* When proportion with BDI scores of 10 or higher were examined, the vitamin B group was 24% more likely to remain free of depressive symptoms (hazard ratio, 1.24), but this was not statistically significant.
* At the end of the study, 79.1% of those receiving vitamin B vs 84.3% of those taking placebo remained free of depression.
* There was no difference in concentrations of B12 and red cell folate or homocysteine levels among men with and without depression.
* The authors concluded that treatment with vitamin B during 2 years was not better than placebo at reducing severity of depressive symptoms or reducing new onset of depressive symptoms in elderly men.
* The authors noted that the effect of vitamin B supplementation as an adjunctive treatment in depression was not known and deserved further investigation.

Pearls for Practice

* Supplementation with vitamin B for 2 years is not associated with reduced depressive symptoms in elderly men.
* Supplementation with vitamin B for 2 years is not associated with lower risk for new onset depressive symptoms in elderly men.

According to this study, which of the following best describes the effect of vitamin B supplementation for 2 years on depressive symptoms in elderly men?
Reduces BDI score
Reduces BDI score only in the first year
No change in BDI score
Reduces BDI score only in the second year

Which of the following best describes the effect of vitamin B supplementation for 2 years on new onset depressive symptoms in elderly men?
Lower risk of new-onset depression
No effect on new-onset depressive symptoms
Lower risk for suicide
Lower risk for depressive symptoms only in those with low folate levels
Instructions for Participation and Credit
There are no fees for participating in or receiving credit for this online educational activity. For information on applicability and acceptance of continuing education credit for this activity, please consult your professional licensing board.

This activity is designed to be completed within the time designated on the title page; physicians should claim only those credits that reflect the time actually spent in the activity. To successfully earn credit, participants must complete the activity online during the valid credit period that is noted on the title page.

FOLLOW THESE STEPS TO EARN CME/CE CREDIT*:

1. Read the target audience, learning objectives, and author disclosures.
2. Study the educational content online or printed out.
3. Online, choose the best answer to each test question. To receive a certificate, you must receive a passing score as designated at the top of the test. Medscape encourages you to complete the Activity Evaluation to provide feedback for future programming.

CME Author

Désirée Lie, MD, MSEd
Clinical Professor, Family Medicine, University of California, Orange; Director, Division of Faculty Development, UCI Medical Center, Orange, California

Disclosure: Désirée Lie, MD, MSEd, has disclosed no relevant financial relationships.

Brande Nicole Martin
is the News CME editor for Medscape Medical News.

Animal Intelligence and the Evolution of the Human Mind

Subtle refinements in brain architecture, rather than large-scale alterations, make us smarter than other animals

By Ursula Dicke and Gerard Roth

As far as we know, no dog can compose music, no dolphin can speak in rhymes, and no parrot can solve equations with two unknowns. Only humans can perform such intellectual feats, presumably because we are smarter than all other animal species—at least by our own definition of intelligence.

Of course, intelligence must emerge from the workings of the three-pound mass of wetware packed inside our skulls. Thus, researchers have tried to identify unique features of the human brain that could account for our superior intellectual abilities. But, anatomically, the human brain is very similar to that of other primates because humans and chimpanzees share an ancestor that walked the earth less than seven million years ago.

Accordingly, the human brain contains no highly conspicuous characteristics that might account for the species’ cleverness. For instance, scientists have failed to find a correlation between absolute or relative brain size and acumen among humans and other animal species. Neither have they been able to discern a parallel between wits and the size or existence of specific regions of the brain, excepting perhaps Broca’s area, which governs speech in people. The lack of an obvious structural correlate to human intellect jibes with the idea that our intelligence may not be wholly unique: studies are revealing that chimps, among various other species, possess a diversity of humanlike social and cognitive skills.

Nevertheless, researchers have found some microscopic clues to humanity’s aptitude. We have more neurons in our brain’s cerebral cortex (its outermost layer) than other mammals do. The insulation around nerves in the human brain is also thicker than that of other species, enabling the nerves to conduct signals more rapidly. Such biological subtleties, along with behavioral ones, suggest that human intelligence is best likened to an upgrade of the cognitive capacities of nonhuman primates rather than an exceptionally advanced form of cognition.

Smart Species
Because animals cannot read or speak, their aptitude is difficult to discern, much less measure. Thus, comparative psychologists have invented behavior-based tests to assess birds’ and mammals’ abilities to learn and remember, to comprehend numbers and to solve practical problems. Animals of various stripes—but especially nonhuman primates—often earn high marks on such action-oriented IQ tests. During World War I, German psychologist Wolfgang Köhler, for example, showed that chimpanzees, when confronted with fruit hanging from a high ceiling, devised an ingenious way to get it: they stacked boxes to stand on to reach the fruit. They also constructed long sticks to reach food outside their enclosure. Researchers now know that great apes have a sophisticated understanding of tool use and construction.

Psychologists have used such behavioral tests to illuminate similar cognitive feats in other mammals as well as in birds. Pigeons can discriminate between male and female faces and among paintings by different artists; they can also group pictures into categories such as trees, selecting those belonging to a category by pecking with their beaks, an action that often brings a food reward. Crows have intellectual capacities that are overturning conventional wisdom about the brain.

Behavioral ecologists, on the other hand, prefer to judge animals on their street smarts—that is, their ability to solve problems relevant to survival in their natural habitats—rather than on their test-taking talents. In this view, intelligence is a cluster of capabilities that evolved in response to particular environments. Some scientists have further proposed that mental or behavioral flexibility, the ability to come up with novel solutions to problems, is another good measure of animal intellect. Among birds, green herons occasionally throw an object in the water to lure curious fish—a trick that, ornithologists have observed, has been reinvented by groups of these animals living in distant locales. Even fish display remarkable practical intelligence, such as the use of tools, in the wild. Cichlid fish, for instance, use leaves as “baby carriages” for their egg masses.

Animals also can display humanlike social intelligence. Monkeys engage in deception, for example; dolphins have been known to care for another injured pod member (displaying empathy), and a whale or porpoise may recognize itself in the mirror. Even some fish exhibit subtle kinds of social skills. Behavioral ecologist Redouan Bshary of the University of Neuchâtel in Switzerland and his colleagues described one such case in a 2006 paper. Bony fish such as the so-called cleaner wrasse (Labroides dimidiatus) cooperate and remove parasites from the skin of other fish or feed on their mucus. Bshary’s team found that bystander fish spent more time next to cleaners the bystanders had observed being cooperative than to other fish. Humans, the authors note, tend to notice altruistic behavior and are more willing to help do-gooders whom they have observed doing favors for others. Similarly, cleaner wrasses observe and evaluate the behavior of other finned ocean denizens and are more willing to help fish that they have seen assisting third parties.

From such studies, scientists have constructed evolutionary hierarchies of intelligence. Primates and cetaceans (whales, dolphins and porpoises) are considered the smartest mammals. Among primates, humans and apes are considered cleverer than monkeys, and monkeys more so than prosimians. Of the apes, chimpanzees and bonobos rank above gibbons, orangutans and gorillas. Dolphins and sperm whales are supposedly smarter than nonpredatory baleen whales such as blue whales. Among birds, scientists consider parrots, owls and corvids (crows and ravens) the brightest. Such a pecking order argues against the idea that intelligence evolved along a single path, culminating in human acumen. Instead intellect seems to have emerged independently in birds and mammals and also in cetaceans and primates.

Heavy Thoughts?
What about the brain might underlie these parallel paths to astuteness? One candidate is absolute brain size. Although many studies have linked brain mass with variations in human intelligence, size does not always correlate with smarts in different species. For example, clever small animals such as parrots, ravens, rats and relatively diminutive apes have brains of modest proportions, whereas some large animals such as horses and cows with large brains are comparatively dim-witted. Brain bulk cannot account for human intelligence either: At eight to nine kilograms, sperm and killer whale brains far outweigh the 1.4 kilograms of neural tissue inside our heads. As heavy as five kilograms, elephant brains are also much chunkier than ours.

Relative brain size—the ratio of brain to body mass—does not provide a satisfying explanation for interspecies differences in smarts either. Humans do compare favorably with many medium and large species: our brain makes up approximately 2 percent of our body weight, whereas the blue whale’s brain, for instance, is less than one 100th of a percent of its weight. But some tiny, not terribly bright animals such as shrews and squirrels win out in this measure. In general, small animals boast relatively large brains, and large animals harbor relatively small ones. Although absolute brain mass increases with body weight, brain mass as a proportion of body mass tends to decrease with rising body weight.

Another cerebral yardstick that scientists have tried to tie to intelligence is the degree of encephalization, measured by the encephalization quotient (EQ). The EQ expresses the extent to which a species’ relative brain weight deviates from the average in its animal class, say, mammal, bird or amphibian. Here the human brain tops the list: it is seven to eight times larger than would be expected for a mammal of its weight. But EQ does not parallel intellect perfectly either: gibbons and some capuchin monkeys have higher EQs than the more intelligent chimpanzees do, and even a few pro­sim­ians—the earliest evolved primates alive today—have higher EQs than gorillas do.

Or perhaps the size of the brain’s outermost layer, the cerebral cortex—the seat of many of our cognitive capacities—is the key. But it turns out that the dimensions of the cerebral cortex depend on those of the entire brain and that the size of the cortex constitutes no better arbiter of a superior mind. The same is true for the prefrontal cortex, the hub of reason and action planning. Although some brain researchers have claimed in the past that the human prefrontal cortex is exceptionally large, recent studies have shown that it is not. The size of this structure in hu­mans is comparable to its size in other ­primates and may even be relatively small as compared with its counterpart in elephants and cetaceans.

The lack of a large-scale measure of the human brain that could explain our performance may reflect the idea that human intellect may not be totally inimitable. Apes, after all, understand cause and effect, make and use tools, produce and comprehend language, and lie to and imitate others. These primates may even possess a theory of mind—the ability to understand another animal’s mental state and use it to guide their own behavior. Whales, dolphins and even some birds boast some of these mental talents as well. Thus, adult humans may simply be more intuitive and facile with tools and language than other species are, as opposed to possessing unique cognitive skills.

Networking
Fittingly, researchers have found the best correlates for intelligence by looking at a much smaller scale. Brains consist of nerve cells, or neurons, and supporting cells called glia. The more neurons, the more extensive and more productive the neuronal networks can be—and those networks determine varied brain functions, including perception, memory, planning and thinking. Large brains do not automatically have more neurons; in fact, neuronal density generally decreases with increasing brain size because of the additional glial cells and blood vessels needed to support a big brain.

Humans have 11.5 billion cortical neurons—more than any other mammal, because of the human brain’s high neuronal density. Humans have only about half a billion more cortical neurons than whales and elephants do, however—not enough to account for the significant cognitive differences between humans and these species. In addition, however, a brain’s information-processing capacity depends on how fast its nerves conduct electrical impulses. The most rapidly conducting nerves are swathed in sheaths of insulation called myelin. The thicker a nerve’s myelin sheath, the faster the neural impulses travel along that nerve. The myelinated nerves in the brains of whales and elephants are demonstrably thinner than they are in primates, suggesting that information travels faster in the human brain than it does in the brains of nonprimates.

What is more, neuronal messages must travel longer distances in the relatively large brains of elephants and whales than they do in the more compact human brain. The resulting boost in information-processing speed may at least partly explain the disparity in aptitude between humans and other big-brained creatures.

Among humans’ cerebral advantages, language may be the most obvious. Various animals can convey complex messages to other members of their species; they can communicate about objects that are not in sight and relay information about individuals and events. Chimpanzees, gorillas, dolphins and parrots can even understand and use human speech, gestures or symbols in constructions of up to about three words. But even after years of training, none of these creatures develops verbal skills more advanced than those of a three-year-old child.

In humans, grammar and vocabulary all but explode at age three. This timing corresponds with the development of Broca’s speech area in the left frontal lobe, which may be unique to humans. That is, scientists are unsure whether a direct precursor to this speech region exists in the nonhuman primate brain. The absence of an intricately wired language region in the brains of other species may explain why, of all animals, humans alone have a language that contains complex grammar. Researchers date the development of human grammar and syntax to between 80,000 and 100,000 years ago, which makes it a relatively recent evolutionary advance. It was also one that probably greatly enhanced human intellect.

Chips Coming to a Brain Near You

By Lakshmi Sandhana

In this era of high-tech memory management, next in line to get that memory upgrade isn't your computer, it's you.

Professor Theodore W. Berger, director of the Center for Neural Engineering at the University of Southern California, is creating a silicon chip implant that mimics the hippocampus, an area of the brain known for creating memories. If successful, the artificial brain prosthesis could replace its biological counterpart, enabling people who suffer from memory disorders to regain the ability to store new memories.

And it's no longer a question of "if" but "when." The six teams involved in the multi-laboratory effort, including USC, the University of Kentucky and Wake Forest University, have been working together on different components of the neural prosthetic for nearly a decade. They will present the results of their efforts at the Society for Neuroscience's annual meeting in San Diego, which begins Saturday.

The hippocampus of the intact brain (left) receives neural impulses from the environment. The microchip (right), which may be able to help humans build long-term memories, processes the signals from the brain as electrical impulses and sends them back into the hippocampus.

While they haven't tested the microchip in live rats yet, their research using slices of rat brain indicates the chip functions with 95 percent accuracy. It's a result that's got the scientific community excited.

"It's a new direction in neural prosthesis," said Howard Eichenbaum, director of the Laboratory of Cognitive Neurobiology at Boston University. "The Berger enterprise is ambitious, aiming to provide a prosthesis for memory. The need is high, because of the prevalence of memory disorder in aging and disease associated with loss of function in the hippocampus."

Forming new long-term memories may involve such tasks as learning to recognize a new face, or remembering a telephone number or directions to a new location. Success depend on the proper functioning of the hippocampus. While this part of the brain doesn't store long-term memories, it re-encodes short-term memory so it can be stored as long-term memory.

It's the area that's often damaged as a result of head trauma, stroke, epilepsy and neurodegenerative disorders such as Alzheimer's disease. Currently, no clinically recognized treatments exist for a damaged hippocampus and the accompanying memory disorders.

Berger's team began its research by studying the re-encoding process performed by neurons in slices of rat hippocampi kept alive in nutrients. By stimulating these neurons with randomly generated computer signals and studying the output patterns, the group determined a set of mathematical functions that transformed any given arbitrary input pattern in the same manner that the biological neurons do. And according to the researchers, that's the key to the whole issue.

"It's an impossible task to figure out what your grandmother looks like and how I would encode that," said Berger. "We all do a lot of different things, so we can't create a table of all the things we can possibly look at and how it's encoded in the hippocampus. What we can do is ask, 'What kind of transformation does the hippocampus perform?'

"If you can figure out how the inputs are transformed, then you do have a prosthesis. Then I could put that into somebody's brain to replace it, and I don't care what they look at -- I've replaced the damaged hippocampus with the electronic one, and it's going to transform inputs into outputs just like the cells of the biological hippocampus."

Dr. John J. Granacki, director of the Advanced Systems Division at USC, has been working on translating these mathematical functions onto a microchip. The resulting chip is meant to simulate the processing of biological neurons in the slice of rat hippocampus: accepting electrical impulses, processing them and then sending on the transformed signals. The researchers say the microchip is doing exactly that, with a stunning 95 percent accuracy rate.

"If you were looking at the output right now, you wouldn't be able to tell the difference between the biological hippocampus and the microchip hippocampus," Berger said. "It looks like it's working."

The team next plans to work with live rats that are moving around and learning, and will study monkeys later. The researchers will investigate drugs or other means that could temporarily deactivate the biological hippocampus, and implant the microchip on the animal's head, with electrodes into its brain.

"We will attempt to adapt the artificial hippocampus to the live animal and then show that the animal's performance -- dependent in these tasks on an intact hippocampus -- will not be compromised when the device is in place and we temporarily interrupt the normal function of the hippocampus," said Sam A. Deadwyler, "thus allowing the neuro-prosthetic device to take over that normal function." Deadwyler, a professor at Wake Forest University, is working on measuring the hippocampal neuron activity in live rats and monkeys.

The team expects it will take two to three years to develop the mathematical models for the hippocampus of a live, active rat and translate them onto a microchip, and seven or eight years for a monkey. They hope to apply this approach to clinical applications within 10 years. If everything goes well, they anticipate seeing an artificial human hippocampus, potentially usable for a variety of clinical disorders, in 15 years.

Overall, experts find the results promising.

"We are nowhere near applicability," said Boston University's Eichenbaum. "But the next decade will prove whether this strategy is truly feasible."

"There is a big gap in making the microchip work in a slice preparation and getting it to work in a human being," added Norbert Fortin, a neuroscientist from the Cognitive Neurobiology Lab at Boston University. "However, their approach is very methodical, and it is not unreasonable to think that in 15 to 20 years such a chip could help, to some degree, a patient who suffered from hippocampal damage."

Free Will vs. the Programmed Brain

If our actions are determined by prior events, then do we have a choice about anything—or any responsibility for what we do?

By Shaun Nichols

Many scientists and philosophers are convinced that free will doesn’t exist at all. According to these skeptics, everything that happens is determined by what happened before—our actions are inevitable consequences of the events leading up to the action—and this fact makes it impossible for anyone to do anything that is truly free. This kind of anti-free will stance stretches back to 18th century philosophy, but the idea has recently been getting much more exposure through popular science books and magazine articles. Should we worry? If people come to believe that they don’t have free will, what will the consequences be for moral responsibility?

In a clever new study, psychologists Kathleen Vohs at the University of Minnesota and Jonathan Schooler at the University of California at Santa Barbara tested this question by giving participants passages from The Astonishing Hypothesis, a popular science book by Francis Crick, a biochemist and Nobel laureate (as co-discoverer, with James Watson, of the DNA double helix). Half of the participants got a passage saying that there is no such thing as free will. The passage begins as follows: “‘You,’ your joys and your sorrows, your memories and your ambitions, your sense of personal identity and free will, are in fact no more than the behavior of a vast assembly of nerve cells and their associated molecules. Who you are is nothing but a pack of neurons.”
The passage then goes on to talk about the neural basis of decisions and claims that “…although we appear to have free will, in fact, our choices have already been predetermined for us and we cannot change that.” The other participants got a passage that was similarly scientific-sounding, but it was about the importance of studying consciousness, with no mention of free will.

After reading the passages, all participants completed a survey on their belief in free will. Then comes the inspired part of the experiment. Participants were told to complete 20 arithmetic problems that would appear on the computer screen. But they were also told that when the question appeared, they needed to press the space bar, otherwise a computer glitch would make the answer appear on the screen, too. The participants were told that no one would know whether they pushed the space bar, but they were asked not to cheat.

The results were clear: those who read the anti-free will text cheated more often! (That is, they pressed the space bar less often than the other participants.) Moreover, the researchers found that the amount a participant cheated correlated with the extent to which they rejected free will in their survey responses.

Varieties of Immorality

Philosophers have raised questions about some elements of the study. For one thing, the anti-free will text presents a bleak worldview, and that alone might lead one to cheat more in such a context (“OMG, if I’m just a pack of neurons, I have much bigger things to worry about than behaving on this experiment!”). It might be that one would also find increased cheating if you gave people a passage arguing that all sentient life will ultimately be destroyed in the heat death of the universe.

On the other hand, the results fit with what some philosophers had predicted. The Western conception idea of free will seems bound up with our sense of moral responsibility, guilt for misdeeds and pride in accomplishment. We hold ourselves responsible precisely when we think that our actions come from free will. In this light, it’s not surprising that people behave less morally as they become skeptical of free will. Further, the Vohs and Schooler result fits with the idea that people will behave less responsibly if they regard their actions as beyond their control. If I think that there’s no point in trying to be good, then I’m less likely to try.

Even if giving up on free will does have these deleterious effects, one might wonder how far they go. One question is whether the effects extend across the moral domain. Cheating in a psychology experiment doesn’t seem too terrible. Presumably the experiment didn’t also lead to a rash of criminal activity among those who read the anti-free will passage. Our moral revulsion at killing and hurting others is likely too strong to be dismantled by reflections about determinism. It might well turn out that other kinds of immoral behavior, like cheating in school, would be affected by the rejection of free will, however.

Is the Effect Permanent?

Another question is how long-lived the effect is. The Vohs and Schooler study suggests that immediately after people are made skeptical of free will, they cheat more. But what would happen if those people were brought back to the lab two weeks later? We might find that they would continue to be skeptical of free will but they would no longer cheat more.

There is no direct evidence on this question, but there is recent evidence on a related issue. Philosopher Hagop Sarkissian of the City Univeristy of New York and colleagues had people from Hong Kong, India, Colombia and the U.S. complete a survey on determinism and moral responsibility. Determinism was described in nontechnical terms, and participants were asked (in effect): whether our universe was a deterministic universe and whether people in a deterministic universe are morally responsible for their actions.
Across cultures, they found that most people said that our universe is not deterministic and also that people in the deterministic universe are not responsible for their actions. Although that isn’t particularly surprising—people want to believe they have free will—something pretty interesting emerges when you look at the smaller group of people who say that our universe is deterministic. Across all of the cultures, this substantial minority of free will skeptics were also much more likely to say that people are responsible even if determinism is true. One way to interpret this finding is that if you come to believe in determinism, you won’t drop your moral attitudes. Rather, you’ll simply reverse your view that determinism rules out moral responsibility.

Many philosophers and scientists reject free will and, while there has been no systematic study of the matter, there’s currently little reason to think that the philosophers and scientists who reject free will are generally less morally upright than those who believe in it. But this raises yet another puzzling question about the belief in free will. People who explicitly deny free will often continue to hold themselves responsible for their actions and feel guilty for doing wrong. Have such people managed to accommodate the rest of their attitudes to their rejection of free will? Have they adjusted their notion of guilt and responsibility so that it really doesn’t depend on the existence of free will? Or is it that when they are in the thick of things, trying to decide what to do, trying to do the right thing, they just fall back into the belief that they do have free will after all?