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The Brain
Written and researched by Bob Murray, PhD
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Lack of Sleep Can Make You Tipsy
September 21, 2003
Scientists in Australia and New Zealand have come up with proof that you can get tipsy just by staying awake. Dr A M Williamson of the School of Psychology, University of New South Wales and colleagues set out to compare the relative effects on performance of sleep depravation and booze.
The subjects, all in the course of science, of course, were observed first over a period of 28 hours of sleep depravation and then again after they consumed measured doses of alcohol up to about 0.1% blood alcohol concentration (BAC).
The team found that after 17-19 hours without sleep the subjects performance in some tests was worse than when they had a blood alcohol level of 0.05% (too drunk to drive a car). Response times were up to 50% slower and accuracy significantly worse than at that BAC.
After longer periods without sleep their reactions were equivalent to BAC levels of 0.1%.
The researchers concluded that lack of sleep is as much a danger factor on the roads and in industrial settings as alcohol consumption.
Read more in Occupational and Environmental Medicine
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Self-esteem Influenced by Body Language
July 8, 2003
When you nod your head to signal approval or shake your head to show disapproval, it's not just sending a message to others--you may also be influencing yourself.
A new study showed that these simple movements influenced people's agreement with an editorial they heard while nodding or shaking their head. Researchers found that other body movements--such as writing with a non-dominant hand--can also influence attitudes, even about important issues such as self-esteem. And these body movements exert their influence without people being aware of what is happening.
"We think of nodding or shaking our head as something that communicates to other people, but it turns out that it is also communicating to ourselves," said Richard Petty, co-author of the study and professor of psychology at Ohio State University.
In a sense, Petty said, nodding or shaking your head, as well as other body movements, serve as a kind of "self-validation" that confirms to us how we feel about our own thoughts. "If we are nodding our heads up and down, we gain confidence in what we are thinking. But when we shake our heads from side to side, we lose confidence in our own thoughts."
Petty conducted the study with Pablo Brinol, a former doctoral student at Ohio State now at the Universidad Autonoma de Madrid in Spain. The research appears in the Journal of Personality and Social Psychology.
In one study, the researchers told 82 college students that they were testing the sound quality of stereo headphones--particularly how the headphones would perform when they are being jostled, as during dancing or jogging. Half the participants were told to move their heads up and down (nodding) about once per second while wearing the headphones. The other half was told to move their heads from side to side (shaking) while listening on the headphones.
All of the participants listened to a tape of a purported campus radio program that included music and a station editorial advocating that students be required to carry personal identification cards.
After listening to the tape, the participants rated the headphones and gave their opinions about the music and the editorial that they heard. The study found that head movements did affect whether they agreed with the editorial. But the effect is more complicated than might be expected. The study found that nodding your head up and down is, in effect, telling yourself that you have confidence in your own thoughts--whether those thoughts are positive or negative. Shaking your head does the opposite: its gives people less confidence in their own thoughts.
So participants in this study who heard an editorial that made good arguments agreed more with the message when they were nodding in a "yes" manner than shaking in a "no" manner. This is because the nodding movements increased confidence in the favorable thoughts people had to the good arguments compared to shaking.
However, students who heard an editorial that made poor arguments showed the reverse pattern. These students agreed less with the message when they were nodding than when shaking. This is because the nodding movements increased confidence in the negative thoughts they had to the poor arguments compared to shaking.
"Nodding your head doesn't mean you'll agree with whatever you hear. One of the most surprising things we found is that if you're thinking negative thoughts while you're nodding, this actually strengthens your disapproval," Petty said. "What the head nodding is doing is making you more confident in your negative thoughts. In contrast, when the thoughts were mostly positive, then nodding increased confidence in these thoughts and thereby increased persuasion."
Another study found the same results occurred even when participants were evaluating something they knew very well: themselves. And it occurred with a completely different kind of body motion: handwriting.
In this case, the participants were asked to write down three good or bad qualities they thought they had with respect to their planned careers. But some were told to write with their right hand, while others were told to write with their left hand (all were determined to be right-handed). They were then asked to rate how confident they were in the thoughts they had listed.
Results showed that the participants had more confidence in their thoughts when they wrote them with their right (dominant) hand than when they wrote with the left (non-dominant) hand.
"As with the head nodding, using the dominant hand affected how confident participants were in their own thoughts," Petty said.
In all the studies, the participants were questioned afterwards to determine if they suspected their head movements or writing with a non-dominant hand influenced their attitudes. None thought so.
Petty said a whole range of body movements, including things such as smiling, as well as other factors such as mood, influence our attitudes to an extent we are unaware. He said it is significant that these body movements can even affect confidence in thoughts about issues in our lives that are important to us and that we have thought about deeply--like our own self-evaluations.
"The fact that this impacts us on our most important decisions and when we are being very thoughtful, that makes this dangerous in some sense," he said. "We have to be very vigilant when we're evaluating our own thoughts. We need to think about why we are confident or not confident in certain attitudes."
In the Uplift Program we stress the importance of catching it every time you make a self-derogatory remark or think a self-derogatory thought as this re-enforces the neural structure around low self-esteem. This research backs up our own findings. BM
Read more in the Journal of Personality and Social Psychology
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Therapy Can Change Brain Neurobiology
May 25, 2003
Brain changes that occur with cocaine use and the tendency toward relapse
may be reduced by a behavioral treatment using extinction training--a
form of conditioning that removes the reward associated with a learned
behavior.
A recent study by researchers at the University of Texas led by Dr David
Self found that specific kinds of training during cocaine withdrawal produces
changes in brain receptors for glutamate, a brain chemical found in the
nucleus accumbens, the reward center of the brain. A reduction in glutamate
input from chronic cocaine use is thought to contribute to persistent
cravings for the drug.
The researchers trained rats to self-administer cocaine by pressing a
lever and to associate the availability of cocaine with certain environmental
cues (lights and noise). Once the rats had learned to expect cocaine when
they pressed the lever, cocaine and the cues were removed so that the
rats did not receive the cocaine that they were anticipating. One group
of rats received this so-called “extinction” training during
cocaine withdrawal while another group did not.
After the training was over, the researchers exposed the rats to the cocaine-associated
cues and administered cocaine to induce relapse. The researchers found
that the rats given extinction training during withdrawal had more than
a 30 percent increase in glutamate receptors in the outer regions of their
nucleus accumbens. The number of glutamate receptors did not increase
in rats that did not receive the training during withdrawal. When cocaine-related
cues were reinstated, rats showing relatively no response to these stimuli
had a greater increase in receptors than rats that responded to the cues.
These findings indicate that behavioral-based treatment approaches have
the potential to reverse or lessen the harmful neurobiological and behavioral
consequences of chronic drug use. Increasing the number of glutamate receptors
may help ease cravings for cocaine during abstinence and also help prevent
relapse.
That therapy can induce neurobiological, and even structural, changes
in the brain is something that we have been saying for some time. In particular,
we believe, that learning and applying certain relationship techniques--which
we call the “needs process”--can cause profound and beneficial
changes in areas of the brain whose growth was stunted by childhood trauma.
Read more in Nature
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Ghosts “All in the Mind”
May 25, 2003
A chill in the air, low-light conditions and even magnetic fields may
trigger feelings that “a presence” is in a room--but that is
all they are, feelings.
This explanation of ghosts is the result of a large study in which researchers
led hundreds of volunteers around two of the UK's supposedly most haunted
locations--Hampton Court Palace, England, and the South Bridge Vaults
in Edinburgh, Scotland.
Dr Richard Wiseman, of the University of Hertfordshire, and his colleagues
say their work has thrown up some interesting data to suggest why so many
people can be spooked in the same building but provides no evidence that
ghosts are real.
In Hampton Court--the alleged haunting place of the executed Catherine
Howard, 5th wife of Henry VIII--the volunteers were asked to keep a record
of their experiences. Did anything unusual happen, such as hearing footsteps,
feeling cold or a presence in the room? They also had to mark the location
and intensity of the experience on a floor plan. Before this, candidates
were asked to reveal any prior knowledge of hauntings at the site.
The researchers then examined the distribution of unusual experiences.
In a “normal” setting, you would expect the ghostly encounters
to be evenly spaced, but in classic haunting, they would be clustered
around certain places.
The results were striking: participants did record a higher number of
unusual experiences in the most classically haunted places of Hampton
Court, areas such as the Georgian rooms and the Haunted Gallery. And in
the Edinburgh vaults, the result was the same--the vaults considered most
haunted were the locations where the most unusual encounters occurred
during the study.
The researchers interpret this as evidence that hauntings are a real
phenomenon because they are concentrated in specific places over time.
“Hauntings exist, in the sense that places exist where people reliably
have unusual experiences,” Wiseman said. “The existence of
ghosts is a way of explaining these experiences.”
But are the ghosts real? Dr Wiseman and his colleagues are not so sure.
They claim, somewhat paradoxically, that the hauntings exist but the ghosts
do not.
“People do have consistent experiences in consistent places, but
I think that this is driven by visual factors mainly, and perhaps some
other environmental cues,” he said. Making detailed measurements
at each place, such as temperature, light intensity and room space, Dr
Wiseman thinks that people are responding unconsciously to environmental
cues and the general "spookiness" of their surroundings.
He cites examples of mediums successfully indicating haunted areas of
buildings with no prior knowledge of them. Spiritualists interpret this
as evidence that the ghosts are there, but another explanation is that
the mediums are simply more sensitive to the environmental cues that result
in haunted feelings--not sensitivity to the ghosts themselves.
Sceptics have long maintained that ghostly encounters are influenced
by a person's knowledge of the place and its history, the “prior
knowledge hypothesis.” But this study refutes that explanation,
as the statistics showed that prior knowledge did not affect the areas
in which strange experiences were recorded. "We found little if no
evidence that people's prior knowledge mattered," said Dr Wiseman.
"If anything, it made them veer away from having experiences in the
known haunted sites."
Read more in the British Journal of Psychology, Dr Wiseman's paper (pdf)
Read more in BBC News
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Smokers Get Timing Wrong
May 25, 2003
New research indicates there's good for the observed phenomenon that
for smokers trying to quit time seems to stand still. It turn out that
time perception, one of the simplest indicators of a person's ability
to concentrate, is severely impaired after just one day without cigarettes,
according to a study in the Psychopharmacology Bulletin.
In the study, 22 nonsmokers and 20 smokers were asked--after 45 seconds--how
much time they thought had passed. Nonsmokers and active smokers were
generally within five seconds of being right. But smokers tested the morning
after a day without cigarettes overestimated the time by an average of
50 percent.
"We had some people (who) thought it was three minutes," said
Laura Cousino Klein, an assistant professor of biobehavioral health who
conducted the study with two Penn State University colleagues.
Timothy B Baker, associate director of the University of Wisconsin's
Center for Tobacco Research and Intervention, said the study might help
smokers better cope with withdrawal. If smokers mistakenly estimate how
long they're experiencing urges, "they may be mis-estimating all
sorts of things that may be making quitting seem more burdensome,"
he said.
Read more in Psychopharmacology Bulletin
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TV News: We Remember What We're Programmed to Remember
April 23, 2003
One of the most unusual, yet persistent, problems television broadcasters face is what researcher Tom Grimes calls "unitentional defamation."
"This takes place when TV news viewers' memory plays tricks on them and they end up 'remembering' the facts of a TV news story in a way that defames an innocent person portrayed in the news story," said Grimes of Kansas State University.
"People tend to use stereotypes to remember a person's role in a news story," Grimes said. "So if a black policeman is shown arresting a white criminal, some viewers may remember the black policeman as the criminal, and the white criminal as the policeman, thus defaming the black policeman."
Grimes said instances in which this type of mistake has happened have led to several defamation suits against both TV stations and networks over the past three decades.
Grimes documented for the first time the components of human memory and information processing that result in this interesting, yet annoying, phenomenon. His research appears this month in the latest issue of the Journal of Broadcasting & Electronic Media.
He and his fellow researchers showed that the phenomenon is a function of stereotyping, and that it can be defeated by activating what psychologists call "semantic elaboration."
"That means making viewers think about what they are seeing and hearing so that they remember the message better," Grimes said. "We also discovered that by showing viewers a photo of a wrong-doer's face before a video new story about that wrong-doer, a viewer's tendency to mis-remember who did what to whom is aborted. This can be done by showing a still shot of the wrong-doer's face next to the news anchor as the news anchor reads the introduction to the video taped news story that contains the wrong-doer. This is an otherwise common production practice in TV news, and is known as a box-wipe."
They discovered that placing a box-wipe of a wrong-doer's face next to the news anchor is especially important when women or minorities are the principal actors in TV news stories in which stereotyping might put them in the role of a wrong-doer.
Read more in the Journal of Broadcasting & Electronic Media
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Is Chronic Fatigue Caused by a Neurological Breakdown?
December 2, 2002
The research shows that subtle changes in a hormonal stress response system called the hypothalamus-pituitary-adrenal (HPA) axis could be a factor in chronic fatigue syndrome. The HPA axis uses three hormones to help the body remain stable during physiological and psychological stress. The hypothalamus secretes a hormone that stimulates the pituitary gland to secrete a second hormone, which then prompts the adrenal gland to produce cortisol. A problem anywhere along that chain can result in a variety of diseases, and that may include chronic fatigue syndrome, the researchers say.
People with chronic fatigue syndrome experience debilitating fatigue and may also have muscle aches, low-grade fever and sleep disturbances.
This study included about 40 people between the ages of 30 and 50. Half of them suffered from chronic fatigue and the other half were healthy. All the study participants filled out questionnaires that measured fatigue, depression and coping skills. The participants were given stress tests and then had blood, cardiovascular and saliva tests to check on their HPA axis.
The study found that people with chronic fatigue syndrome had significantly lower response levels of one of the HPA hormones called ACTH before and during the stress tests.
Read more in Psychosomatic Medicine
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Talk For Your Life
November 12, 2002
A new set of studies suggests that it may be just part of the solution. Simply talking to people, the researchers say, appears to keep mental skills sharp.
Humans are social animals, and new studies are bringing researchers to the conclusion that indulging our genetically-based social instincts are the best medicine we can take. The studies, by psychologists from the University of Michigan and the University of Denver, argue that ordinary day-to-day contact is at least as useful, for example, as more formal intellectual activities in preserving mental acuity.
"When people interact with others, basic processes such as working memory, speed of processing and verbal knowledge come into play," the authors wrote. "But social interaction also entails responding to others with our vision, hearing, touch and even smell. It is hard to conceive of a math problem or a novel affecting us in all these ways."
Still, it is not simply a matter of more social contacts leading to a sharper mind. People in better shape mentally are probably more inclined to be social in the first place, the study said. Which is cause and which is effect is not clear, and each may be a bit of both.
"I think in the end it's going to be dynamic," said the lead author, Dr Oscar Ybarra of the University of Michigan. The study was reported in The New York Times. Dr Ybarra said he and his colleagues were responding to a widespread assumption that to keep the brain sharp people needed to engage in intellectual activities. But with many elderly people isolated, the researchers said, it was important not to overlook other factors in mental decline.
The studies were based on earlier research that did not look directly at the association between social activity and cognitive ability, but nevertheless produced data that shed light on the issue. In all the studies, researchers asked participants about social lives and assessed mental skills with simple tests. Dr Barra and his colleagues took that information and correlated it.
They found a close connection between how much social contact people reported and how well they did when asked to do tasks like count backward by three or recall something. "The main findings," the authors wrote, "can be summarized as follows: The more people are socially engaged, the better off they are cognitively."
Read more in The New York Times
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Nature or Nurture Revisited
November 12, 2002
According to an article published recently in The New York Times, neuroscientists have found an evocative solution to a classic problem: which is more important in shaping the human brain, nature or nurture?
The answer they have come up with is: both. The brain is not primarily the product of genes, they say, but neither is it simply the sum of one's experiences. Rather, they say, each human brain is constructed of complex neural circuits that start taking shape before birth and continue to grow and change throughout life as genes and cells are influenced by environment, experience and culture.
There is widespread agreement that genes and environment interact in brain development, said Dr. Terrence J. Sejnowski, a neuroscientist at the Salk Institute in San Diego, and a leading proponent of the new synthesis. The new idea, he said, is that human cultures, which teach children what to believe and what to expect in life, interact with cell biology and molecular genetics to assemble the highly social human brain.
Though everyone's brain begins with "a basic scaffold of connectivity that is formed according to genetic blueprints," said Dr Carla Shatz, a developmental neurobiologist at Harvard Medical School, "a baby's brain is not a miniature of the adult's, but rather is a dynamically changing structure." Experience alters brain structure, chemistry and gene expression to sculpture immature neural circuits into adult circuitry, she said. In short, the theory's advocates say, while the brain directs people's activities in everyday life, the activities themselves shape the brain throughout life.
"The attempt to separate genes and environment is a mistake," said Dr Steven R Quartz, a scientist at the California Institute of Technology. "What makes us who we are is a complex interplay of early experiences, parenting, birth order, friends, genes and how these forces interact."
Humans are born with temperaments arising from genetic variations in brain chemicals called neuromodulators, Dr. Quartz was quoted in the Times as saying. These differences may lead one baby to avoid novelty and another to seek it. But the experiences that result help construct the growing brain. Humans are also born with a very large prefrontal cortex, a higher brain region involved in planning that taps into an ancient system for predicting what is rewarding and making decisions to maximize rewards and avoid punishments.
Neuroscientists are finding that this circuit, which fully matures in late adolescence, is an internal guidance system that fills each person's world with values, meaning and emotional tone, taking shape according to a person's culture. In other words, culture contributes not just to the brain's contents but to its wiring as well.
Funnily enough, we have been saying much the same thing for the last five years. It just seemed obvious from the previous research. BM
Read more in The New York Times
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Stress Illness Linked to Brain Shape
October 22, 2002
The chances of combat veterans, civilian victims of war and disaster survivors experiencing psychological damage may be determined by the shape of their brains before the trauma hits them, scientists have found.
Researchers in the US looked at 40 pairs of identical twins where one twin had seen combat in Vietnam and the other had stayed at home. More than 40% of the Vietnam veterans suffered from post-traumatic stress disorder, and a clear link was found between the size of a region of their brains, the hippocampus, and which veterans were affected.
Previously it was thought the hippocampus, which is in a central part of the brain, had been damaged by the disorder. But the US researchers found that the stay-at-home siblings of PTSD-suffering veterans also had smaller than average hippocampi. In other words, say the scientists in the latest online edition of Nature Neuroscience, some GIs sent into combat were doomed to suffer the harsh consequences of PTSD.
People with the disorder experience flashbacks and nightmares. PTSD sufferers display emotional numbness or outbursts and problems with memory and concentration. Sometimes their symptoms are complicated as they turn to drugs such as alcohol in a form of self-treatment. It affects not only victims of war and natural disasters but those who have suffered violence, sexual abuse, bullying and other situations of extreme stress.
Much work will need to be done before the new findings are widely accepted, but if they are, they may lead to brain screening in recruitment for jobs like soldiering or police work which involve experiencing extreme events.
The PTSD study, led by Mark Gilbertson of the Veterans Administration Medical Centre in New Hampshire, tried to account for factors like the tendency towards alcoholism among sufferers. They admitted there were flaws, however, such as the fact that small hippocampi have been observed only in those who have suffered PTSD after sustained periods of high-stress experience, not in those who have suffered a single high-stress episode, like a serious car accident.
Previous studies have shown that depression is linked to a smaller hippocamput and that childhood trauma is probably the cause. BM
Read more in Psychport
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About the Author
Dr Bob Murray is a widely published psychologist and expert on emotional health and optimal relationships. Together with his wife and long-term collaborator Alicia Fortinberry, he is founder of the highly successful Uplift Program, and author of Raising an Optimistic Child (McGraw-Hill, 2006) and Creating Optimism (McGraw-Hill, 2004).
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