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What “LIES” Beneath…

liedef


The most important fundamental principle in Psychiatry is discovering the content of our “self-talk”. 

cbt

Cognitive behavioral therapy (CBT), introduced by Dr. Aaron Beck, has been established as a very useful therapy for those suffering from a wide range of emotional problems.  The effective application of this therapy has been a powerful tool not only for troubled individuals but for anyone who desires some sort of compass to navigate through the rocky terrain of everyday life.

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The principles are based on uncovering the lies we have learned throughout our lives and how they introduce obstacles when we hold them as truths.  The most valuable aspect of CBT is that it does not require a lifelong therapist. In fact, the pace of healing is centered on those who earnestly acquire the skills to keep their mental dialogue in check.  When we learn how to extract truth in our interpretations of life events, we are able to break free from the anxiety and fear that threaten our freedom to live life fully as intended,

Here, I will share the six basic lies that rob our freedoms.  If you learn how to identify these lies, then you will be in a position to begin replacing your self-dialogue with truths and begin a journey to freedom.

6lies

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Now, Go Reclaim your freedom!

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The Bridge that could not..

 

 

nobridge

 

I have heard it said “if you want friends, do not build walls, build bridges”. But if you have ever felt depressed or under stress, you may have noticed that you did not really feel very sociable.  In fact, you may remember that you avoided being around people. You may even recall how stress impaired your thinking and planning. We tend to become myopic, or near sighted and any task undertaken can seem very energy demanding.

I have been reading an article recently that explains how this experience is actually a part of a neurobiological process ; one that is common not only for times of stress and depression, but it also appears to have a common involvement in most dementias.

You see, the bridgework of social engagement is much like the bridgework that can be found between neurons of our brains.  This bridgework aligns neurons across the a signalling gap between downstream neurons.  The terminal end of one firing neuron (presynapse) communicates with the dendrite (postsynapse)  of the next neuron through a gap known as a synapse.

synapse

synbridge

The alignment of neurons is an important feature for effective communication downstream.  Researchers discovered a structure protein known as Nectin-3 that maintains this alignment to secure connections in place.  Now, what has been found is that when mice were placed in a stressful environment, there was a significant reduction in Nectin-3 in their brains.  This also correlated with the avoidance behaviour observed in these mice from the stress induced.  In order to be certain of this relationship, other experiments were designed to restore  fibronectin-3, which resulted in increased cognitive function and improved  socialization in mice.

When the scientist explored the mechanism behind nectin-3 reduction, an enzyme known as MMP-9 was identified.  During times of stress, high glutamate levels prompt the release of this enzyme which degrades  nectin-3 protein. I think of this as Military Police (MP) that lose their role as peacekeepers, causing mass chaos.

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Normally, this enzyme has an important role, probably in modifying memory like fine tuning a piano to the right tone.  However, stress clearly permits a runaway mechanism to hinder our social interaction and capacity to think clearly.

 

I invite you to read this article below.


Stress Management Makes Us Antisocial Due To Severed Synapses: New Finding Opens Window For Disorder Treatment

grouchy
If you find yourself avoiding human interaction when you’re stressed, be sure to thank an enzyme in your brain. greg westfall, CC BY 2.0

The people who can carry on amiable conversation while also fighting a war inside their heads are few and far between. When we get stressed, we shut down.We recede from the social sphere, if only to count to 10, before rejoining the group with a clearer frame of mind. But what, exactly, is going on between our ears when all this is happening?

New research from the Brain Mind Institute at École polytechnique fédérale de Lausanne (EPFL), in Switzerland, suggests the neural mechanism that makes stress a precursor to antisocial behavior happens at the synaptic level. Specifically, there is a disruption between a key enzyme and a set of proteinsnecessary for sociability. Keeping that relationship intact could open important doors for the treatment of psychiatric disorders.

There’s a type of protein whose main function in the brain is to keep neurons stuck together. They’re called adhesion proteins, and one in particular, the nectin-3 adhesion protein, has been found in prior research to play a vital role in the preservation of cognitive functions. In rats with chronic stress, researchers recently found nectin-3 levels were substantially lower.

In looking for possible causes of the decrease, the researchers ended up at the enzyme MMP-9, known for its role in protein degradation. What they found when they looked at MMP-9 activity in the brain was that during episodes of chronic stress, when the neurotransmitter glutamate is released, the receptors responsible for memory and synaptic plasticity activated MMP-9. Literally like scissors, the enzyme cut the nectin-3 proteins.

“When this happens, nectin-3 becomes unable to perform its role as a modulator of synaptic plasticity” explained lead author and Brain Mind Institute professor Carmen Sandi in a statement. The end result for the rats was decreased sociability, avoidant behavior, and impaired memory and understanding.

By contrast, when EPFL researchers and a team of Polish scientists tried to reverse the effect — in other words, boost sociability through nectin-3 restoration — they found in in vitro and in vivo models that these external treatments yielded positive effects. Cognitive skills improved and memory returned. “The identification of this mechanism is important because it suggests potential treatments for neuropsychiatric disorders related to chronic stress, particularly depression,” Sandi said.

The research is admittedly early for any clinical application. So far, no drugs have been developed using nectin-3 as their primary target. Sandi and her team hope the findings can be repeated in future studies. Given the success with MMP-9, they also hope to exploit its benefits for other neurological diseases, like amyotrophic lateral sclerosis or epilepsy.

“This result opens new research avenues on the still unknown consequences of chronic stress,” Sandi said.

Source: Sandi C, et al. Nature Communications. 2014.

 

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Cats on the Brain

Does the Cat have your tongue? How about your brain?

Does the Cat have your tongue? How about your brain?

I remember from Medical School that there are dangers related to infections from some pets.  One, in particular, was the risk of pregnant women having exposure to cat waste.  It is well established that cats carry toxoplasmosis can be very harmful to the developing fetus.  Birth defects and death can result from exposure to the parasite, often abundant in cat waste.

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I also recall that some people suffering from compromised immunity are also susceptible to the same parasite which can spread throughout the body and especially the brain.

However, I have been reading about how this parasite has a greater range of impact on its host.  Apparently, this microbe has a very practical function as well for our feline companions.  It seems that mice become susceptible to the parasite, which erodes their natural defenses.  Mice have a particular agility and acuity to avoid entrapment.  But this infection makes mice less anxious and careless about being discovered.  In fact, mice can become allured to the waste of their predators, allowing them to be easy prey,

The articles below will describe this study and further present concerns about the similar mechanism of infection that can have a profound impact on human behavior. Some people can be influenced by a subacute infection that is just attributed to nothing more than a trait of character. A question we have to consider is ‘just how much can mental and behavioral management can be manipulated beyond our conscious knowledge or Will’?


Sep 18

Cat poop parasite controls minds early — and permanently, study finds

STORY BY MAGGIE FOX
WENDY INGRAM AND ADRIENNE GREENE
Even after infection with Toxoplasma gondii has been removed from rodents’ brains, they continue to behave as if unafraid of the smell of cat urine, suggesting that the infection causes long-term changes in the brain.
A parasite that changes the brains of rats and mice so that they are attracted to cats and cat urine seems to work its magic almost right away, and continues to control the brain even after it’s gone, researchers reported on Wednesday.

The mind-controlling parasite, called Toxoplasma gondii, might make permanent changes in brain function as soon as it gets in there, the researchers report. They aren’t sure how yet.

“The parasite is able to create this behavior change as early as three weeks after infection,” says Wendy Ingram of the University of California, Berkeley, who worked on the study.

T. gondii has captured the imaginations of scientists and cat lovers ever since it was learned it can control the behavior of rodents. It changes their brains so they lose their innate fear of the smell of cat urine. In fact, it precisely alters their fear reaction so that they love the smell of cat pee.

This makes infected rodents much more likely to be caught by cats, which eat them and their mind-controlling parasites. T. gondii can only reproduce in the guts of cats, so its behavior directly affects its own survival.

It doesn’t just affect cats. People can be infected too — pregnant women are told to stay away from cat feces for this very reason. It normally doesn’t bother people, but it can cause brain inflammation, called encephalitis, in some — especially those with compromised immune systems like pregnant women.

“More than 60 million men, women, and children in the U.S. carry the Toxoplasma parasite, but very few have symptoms because the immune system usually keeps the parasite from causing illness,” the Centers for Disease Control and Prevention says on its website.

WENDY INGRAM AND ADRIENNE GREENE
Chronic infection with the parasite Toxoplasma gondii can make mice lose their innate, hard-wired fear of cats.

Studies have linked toxoplasmosis with a range of human mental diseases, including schizophrenia, bipolar disease, obsessive-compulsive disorder and even clumsiness. This study doesn’t answer questions about people, Ingram points out.

“It does not necessarily explain crazy cat ladies or why there are LOLCATS online,” she says.

But it does begin to hint at a potential mechanism for how and when the parasite changes the mouse brains.

“I want to know how the behavioral change is happening,” Ingram says.

Her team used a specially genetically engineered version of the parasite, made by a team at Stanford University.

Normal T. gondii parasites form a cyst in neurons. “It was assumed that the cysts … were doing something biologically that is actively changing the behavior,” Ingram told NBC News.

But the genetically engineered parasite wasn’t able to make cysts. And it was so weak that the rats’ immune systems were able to clear it from their brains. But even so, rats infected with this weakened form of the parasite just loved the smell of cat urine, Ingram and colleagues report in the Public Library of Science journal PLoS ONE.

“This suggests the parasite is flipping a switch rather than continually changing the behavior,” says Ingram.

She suspects it’s somehow activating the immune system in a way that then alters brain function. “That’s one of the very first things I am going to be checking,” Ingram says.

First published September 18th 2013, 7:03 pm

 

 
 

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Slideshow Presentation: Revealing your Child’s behavior in Context

Presentation Given to Parents in Atibia, Brazil.

Here I discussed importance of knowing your child in context. I also discussed a brief method of Psychiatry in assessing cognitive emotional function.  Further, I touched on aspects of attention problems and the role of anxiety in obstructing focus and its contribution to disease. I ended with a brief overview of neuroscience and the important role of keeping anxiety in check.  I believe this presentation can be useful to many, as it is to my daily self maintenance.

philos1

Revealing Your Childs Behavior in Context

 

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Making Scents of Fear

smellfear          "Don't smell of fear(??)!"

 

micepupsMany years ago, I had the pleasure to work as a research scientist in Germany.  I remember a profound discovery discussed in one of our lectures.  It was about an experiment conducted where a young adult female mouse was removed from a cage with her pups and placed in a stressful situation. Following the stress, the mother was returned to her pups. When the stress hormone was measured in the the adult mouse later, the resting stress level (cortisol) was elevated.  However, when the pups stress level was measured, it was found that their levels of cortisol were elevated from baseline measures as well. Some speculated that there was a change in the mother’s milk, that conveyed the change in fear threshold of her pups.  However, there was no chemical change discovered.  The mother’s initial aggitation would recover in a short time, yet there seemed to be a sustained change in cortisol level of the mother and the pups. Even though the pups were not exposed to the same stress.  Further, the pups  continued to possess an elevated stress level for a significant duration of time. Now based on this study, we see more clearly how the very scent of moms can reset the fear threshold of their infants.  Here is another great example of epigenetics.  There remains a mystery as how this information is related. Read the following article for more details.  

 


Learning the smell of fear: Mothers teach babies their own fears via odor, research finds

Research in rats may help explain how trauma’s effects can span generations

ANN ARBOR, Mich. — Babies can learn what to fear in the first days of life just by smelling the odor of their distressed mothers, new research suggests. And not just “natural” fears: If a mother experienced something before pregnancy that made her fear something specific, her baby will quickly learn to fear it too — through the odor she gives off when she feels fear.

In the first direct observation of this kind of fear transmission, a team of University of Michigan Medical School and New York University studied mother rats who had learned to fear the smell of peppermint – and showed how they “taught” this fear to their babies in their first days of life through their alarm odor released during distress.

In a new paper in the Proceedings of the National Academy of Sciences, the team reports how they pinpointed the specific area of the brain where this fear transmission takes root in the earliest days of life.

Their findings in animals may help explain a phenomenon that has puzzled mental health experts for generations: how a mother’s traumatic experience can affect her children in profound ways, even when it happened long before they were born.

The researchers also hope their work will lead to better understanding of why not all children of traumatized mothers, or of mothers with major phobias, other anxiety disorders or major depression, experience the same effects.

“During the early days of an infant rat’s life, they are immune to learning information about environmental dangers. But if their mother is the source of threat information, we have shown they can learn from her and produce lasting memories,” says Jacek Debiec, M.D., Ph.D., the U-M psychiatrist and neuroscientist who led the research.

“Our research demonstrates that infants can learn from maternal expression of fear, very early in life,” he adds. “Before they can even make their own experiences, they basically acquire their mothers’ experiences. Most importantly, these maternally-transmitted memories are long-lived, whereas other types of infant learning, if not repeated, rapidly perish.”

Peering inside the fearful brain

Debiec, who treats children and mothers with anxiety and other conditions in the U-M Department of Psychiatry, notes that the research on rats allows scientists to see what’s going on inside the brain during fear transmission, in ways they could never do in humans.

He began the research during his fellowship at NYU with Regina Marie Sullivan, Ph.D., senior author of the new paper, and continues it in his new lab at U-M’s Molecular and Behavioral Neuroscience Institute.

The researchers taught female rats to fear the smell of peppermint by exposing them to mild, unpleasant electric shocks while they smelled the scent, before they were pregnant. Then after they gave birth, the team exposed the mothers to just the minty smell, without the shocks, to provoke the fear response. They also used a comparison group of female rats that didn’t fear peppermint.

They exposed the pups of both groups of mothers to the peppermint smell, under many different conditions with and without their mothers present.

Using special brain imaging, and studies of genetic activity in individual brain cells and cortisol in the blood, they zeroed in on a brain structure called the lateral amygdala as the key location for learning fears. During later life, this area is key to detecting and planning response to threats – so it makes sense that it would also be the hub for learning new fears.

But the fact that these fears could be learned in a way that lasted, during a time when the baby rat’s ability to learn any fears directly was naturally suppressed, is what makes the new findings so interesting, says Debiec.

The team even showed that the newborns could learn their mothers’ fears even when the mothers weren’t present. Just the piped-in scent of their mother reacting to the peppermint odor she feared was enough to make them fear the same thing.

And when the researchers gave the baby rats a substance that blocked activity in the amygdala, they failed to learn the fear of peppermint smell from their mothers. This suggests, Debiec says, that there may be ways to intervene to prevent children from learning irrational or harmful fear responses from their mothers, or reduce their impact.

From animals to humans: next steps

The new research builds on what scientists have learned over time about the fear circuitry in the brain, and what can go wrong with it. That work has helped psychiatrists develop new treatments for human patients with phobias and other anxiety disorders – for instance, exposure therapy that helps them overcome fears by gradually confronting the thing or experience that causes their fear.

In much the same way, Debiec hopes that exploring the roots of fear in infancy, and how maternal trauma can affect subsequent generations, could help human patients. While it’s too soon to know if the same odor-based effect happens between human mothers and babies, the role of a mother’s scent in calming human babies has been shown.

Debiec, who hails from Poland, recalls working with the grown children of Holocaust survivors, who experienced nightmares, avoidance instincts and even flashbacks related to traumatic experiences they never had themselves. While they would have learned about the Holocaust from their parents, this deeply ingrained fear suggests something more at work, he says.

Going forward, he hopes to work with U-M researchers to observe human infants and their mothers — including U-M psychiatrist Maria Muzik, M.D. and psychologist Kate Rosenblum, Ph.D., who run a Women and Infants Mental Health clinic and research program and also work with military families. The program is currently seeking women and their children to take part in a range of studies; those interested in learning more can call the U-M Mental Health Research Line at (734) 232-0255.

The research was supported by the National Institutes of Health (DC009910, MH091451), and by a, NARSAD Young Investigator Award from the Brain and Behavior Research Foundation, and University of Michigan funds. Reference: http://www.pnas.org/cgi/doi/10.1073/pnas.1316740111

 

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The Edge of Good Bye, balancing the choice to live on


suicidepro

The edge of Goodbye


We may have a biochemical marker in the near future which can help flag those who are prone to suicidal attempts.  Researchers at John Hopkins University have discovered a gene that helps regulate the stimulation of cortisol.  When pressures mount, this gene, (known as SKA) apparently helps to limit the cortisol impact on the cortical receptors within the forebrain. Those individuals prone to suicidal activity were found to consistently have low SKA expression.

 

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Cortisol: the train

A good way for me to conceptualize this process is to think of cortisol as a speeding train moving through the brain.  It is set in motion by a perceived  stress we are experiencing.  Ideally, the cortisol prepares our bodies for a “get up and go” necessary to meet our challenges.  However, the brakes are necessary to slow the train down in order to remain in control of the moment. So if the cortisol is the train, then the SKA gene is the brakes.

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SKA:the breaks of the train

Studies have shown that the SKA gene remains unchanged in our makeup.  However, our life experiences can influence the expression of this SKA gene (known as epigenetic regulation). As you may grasp, when the expression of SKA is hindered, the cortisol released during periods of stress has no way to regulate activity downstream.  Cortisol becomes a runaway train. Life can become a train wreck.

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Train wreck


See attached Article

A blood test for suicide?

Alterations to a single gene could predict risk of suicide attempt

Johns Hopkins researchers say they have discovered a chemical alteration in a single human gene linked to stress reactions that, if confirmed in larger studies, could give doctors a simple blood test to reliably predict a person’s risk of attempting suicide.

The discovery, described online in The American Journal of Psychiatry, suggests that changes in a gene involved in the function of the brain’s response to stress hormones plays a significant role in turning what might otherwise be an unremarkable reaction to the strain of everyday life into suicidal thoughts and behaviors.

“Suicide is a major preventable public health problem, but we have been stymied in our prevention efforts because we have no consistent way to predict those who are at increased risk of killing themselves,” says study leader Zachary Kaminsky, Ph.D., an assistant professor of psychiatry and behavioral sciences at the Johns Hopkins University School of Medicine. “With a test like ours, we may be able to stem suicide rates by identifying those people and intervening early enough to head off a catastrophe.”

For his series of experiments, Kaminsky and his colleagues focused on a genetic mutation in a gene known as SKA2. By looking at brain samples from mentally ill and healthy people, the researchers found that in samples from people who had died by suicide, levels of SKA2 were significantly reduced.

Within this common mutation, they then found in some subjects an epigenetic modification that altered the way the SKA2 gene functioned without changing the gene’s underlying DNA sequence. The modification added chemicals called methyl groups to the gene. Higher levels of methylation were then found in the same study subjects who had killed themselves. The higher levels of methylation among suicide decedents were then replicated in two independent brain cohorts.

In another part of the study, the researchers tested three different sets of blood samples, the largest one involving 325 participants in the Johns Hopkins Center for Prevention Research Study found similar methylation increases at SKA2 in individuals with suicidal thoughts or attempts. They then designed a model analysis that predicted which of the participants were experiencing suicidal thoughts or had attempted suicide with 80 percent certainty. Those with more severe risk of suicide were predicted with 90 percent accuracy. In the youngest data set, they were able to identify with 96 percent accuracy whether or not a participant had attempted suicide, based on blood test results.

The SKA2 gene is expressed in the prefrontal cortex of the brain, which is involved in inhibiting negative thoughts and controlling impulsive behavior. SKA2 is specifically responsible for chaperoning stress hormone receptors into cells’ nuclei so they can do their job. If there isn’t enough SKA2, or it is altered in some way, the stress hormone receptor is unable to suppress the release of cortisol throughout the brain. Previous research has shown that such cortisol release is abnormal in people who attempt or die by suicide.

Kaminsky says a test based on these findings might best be used to predict future suicide attempts in those who are ill, to restrict lethal means or methods among those a risk, or to make decisions regarding the intensity of intervention approaches.

He says that it might make sense for use in the military to test whether members have the gene mutation that makes them more vulnerable. Those at risk could be more closely monitored when they returned home after deployment. A test could also be useful in a psychiatric emergency room, he says, as part of a suicide risk assessment when doctors try to assess level of suicide risk.

The test could be used in all sorts of safety assessment decisions like the need for hospitalization and closeness of monitoring. Kaminsky says another possible use that needs more study could be to inform treatment decisions, such as whether or not to give certain medications that have been linked with suicidal thoughts.

“We have found a gene that we think could be really important for consistently identifying a range of behaviors from suicidal thoughts to attempts to completions,” Kaminsky says. “We need to study this in a larger sample but we believe that we might be able to monitor the blood to identify those at risk of suicide.”

Along with Kaminsky, other Johns Hopkins researchers involved in the study include Jerry Guintivano; Tori Brown; Alison Newcomer, M.Sc.; Marcus Jones; Olivia Cox; Brion Maher, Ph.D.; William Eaton, Ph.D.; Jennifer Payne, M.D.; and Holly Wilcox, Ph.D.

The research was supported in part by the National Institutes of Health’s National Institute of Mental Health (1R21MH094771-01), the Center for Mental Health Initiatives, The James Wah Award for Mood Disorders, and The Solomon R. and Rebecca D. Baker Foundation.

More information:

http://www.hopkinsmedicine.org/profiles/results/directory/profile/5411152/zachary-kaminsky

http://www.hopkinsmedicine.org/news/media/releases/genetic_predictors_of_postpartum_depression_uncovered_by_johns_hopkins_researchers

Johns Hopkins Medicine (JHM), headquartered in Baltimore, Maryland, is a $6.7 billion integrated global health enterprise and one of the leading health care systems in the United States. JHM unites physicians and scientists of the Johns Hopkins University School of Medicine with the organizations, health professionals and facilities of The Johns Hopkins Hospital and Health System. JHM’s vision, “Together, we will deliver the promise of medicine,” is supported by its mission to improve the health of the community and the world by setting the standard of excellence in medical education, research and clinical care. Diverse and inclusive, JHM educates medical students, scientists, health care professionals and the public; conducts biomedical research; and provides patient-centered medicine to prevent, diagnose and treat human illness. JHM operates six academic and community hospitals, four suburban health care and surgery centers, and more than 30 primary health care outpatient sites. The Johns Hopkins Hospital, opened in 1889, was ranked number one in the nation for 21 years in a row by U.S. News & World Report.

Media Contact:

Lauren Nelson
410-955-8725; lnelso35@jhmi.edu

Helen Jones
410-502-9422; hjones49@jhmi.edu

 

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Gender Minds

argue

 

My wife and I are united in purpose, convictions and moral character.  We share values which are regarded as essential.  We love each other and grow in our love for each other.  Though united in common points, we are clearly different people. Her capacity to multitask, her broad social connections, her depth of emotional investment are clearly not built into my design.  I am unable to handle more than one tasks at a given time. Though happy in the community of friends, I often prefer seclusion and research in a corner somewhere. I am more apt to lean on logic and determine a clear course of action than rehash emotional dialogue, and try to forecast how my actions may stir emotional turbulence.   I have a son and daughter under in their early teens.  After school I ask, “how was your day?” . My son will just say, “fine”.  The rest of the ten minute ride home, my daughter will give me a moment by moment narrative, including emotional tones , appearance of her involved friends that day; detailing every sequential step with her relationships.  I love them both.  But, I have to admit, it is much easier on my concentration to accept “fine” than to labor with my focus on elaborative reenactments.  I would not change either one, and I know these are rare and prized moments I will cherish.  But this vast difference between their modality of life is more than just personality.  It is more about their gender design.  One prominent theory states that testosterone, the male hormone is produced at a critical period of a boy’s development, shrinks the bundle of nerve fibers that ties the right and left brain hemispheres together.  This narrowing results in males becoming more left hemisphere logic dominant in cognition. While females evolve into whole brain cognition, laden with emotional content prominence. The woman’s intuition (whole brain summation) is accredited to this wiring design.  This leads to a challenging dialogue with their male counterparts asking,”..but tell me why you don’t like John Smith (give me a logical reason)? The spouse replies “I can not explain it, but I do not trust him (whole brain summation)”. Often, the suspicious woman will be found more accurate than what reason could provide.  I have often shared with couples in counseling that we (males) are just half brained,  Many marriages could avoid erosion if it could be understood up front that the design differences and not willful acts are behind the actions we display.

Here are some articles on this topic.  Enjoy!

Greg E. Williams, MD

Reference
Clearly. “Sex Differences.” About Gender: Sex Differences. Gender, n.d. Web. 26 July 2014.http://www.gender.org.uk/about/07neur/77_diffs.htm.

(http://www.gender.org.uk/about/07neur/77_diffs.htm)


 

Sex Differences

The Nervous System Nerves. The Brain The Cerebral Cortex Theories About Thinking Sex Differences

Corpus callosum.

The corpus callosum itself has attracted the attention of biologists searching for sex differences. It will be remembered that it was surgery to sever it that drew attention to the differing organisation of the two sides of the cortex.

There is a great deal of dispute about whether there are reliable average differences between the sexes. Originally, it was claimed that it was larger overall in women, relative to brain size. Later the claim was that the posterior portion, the splenium was larger.

Fausto-Stirling(1,2) is extremely critical of studies in this area. Since 1982 there have been at least seventeen papers published. Since no two approach the problem in the same way, she suggests that none of them corroborate each other. What does appear is that there are changes with age, yet only one of the studies used age-matched subjects. Also, if there any sex differences at all, they show up after birth, possibly not until after adolescence.

Considering the millions of axons which must traverse this region, there is no total picture of their path. Larger nerve bundles can be traced leading to the front and back but, though a reasonable general rule is for them to take the shortest path, this is by no means inflexible..

The result of differences in the corpus callosum are said to result in a greater relative fluency of thought and speech. Reminding ourselves that no-one has actually counted the number of axons, nor traced their connections, we are told that this results in greater communication between the cerebral hemispheres of women. It is suggested that women’s greater sensitivity to emotional, non verbal communication, even their intuition, comes from the greater connectivity in their minds. A man is more purpose orientated. Emotions are kept on the right side of his brain, which, being less connected to the left, mean that he can, less easily, express emotions. Clearly, biological effects are not the whole story, for men are expected to be relatively unemotional.

There is another structure that connects between the cerebral hemispheres, the anterior commissure. It communicates visual, olfactory and auditory information and is larger in women than men. Allen has demonstrated that it is also larger in homosexual men.

Size isn’t everything.

A myth that surfaces, from time to time, is one from the nineteenth century that purported to show that women have smaller brains than men. It had been put forward in the nineteenth century in an effort to prove that women (and black people) were inferior. The authors of that time had not taken account of the fact that women are, or were, in general smaller overall than men. Even then it was pointed out that there was such a wide variation, an enormous sample size would needed to show a significant difference.

Was it, then, true? And why did it matter? Fausto-Sterling answers the first question fairly effectively. “the average male/female difference in brain weight for all ages is 9.8%. when charted as a function of either height or weight, however, the difference in adults virtually disappeared.” This from a study of over four thousand subjects.(3)

What matters is the complexity of the cortex. If overall size was all that mattered, elephants would have a considerable intellect. The human cerebral cortex contains some ten to fifteen thousand million neurons, with four times as many glial cells, and one million billion synaptic connections. Spread out, the total surface area would cover about three quarters of a square metre.

Sex and lateralisation.

Where the gender debate first arose, was from claims about differences between men and women in the way they use the two halves of the cortex.

The original hypothesis was that men used their logical left side while women used the emotional irrational right side. However, the argument soon arose that, if language was a function of the left side, how was it that women were better at expressing themselves verbally?

This is rather a simplistic view of the controversy, however, the theory was modified to suggest men have greater lateralisation, that their abilities are more compartmentalised, while, in women utilisation of the two halves is more diffuse.

From the sixties onward, Landsell was working with people who had damage to one side of the cortex or the other. The knowledge of the time indicated that damage to the left hemisphere should lead to deficits in verbal tasks, while right-side damage should produce deficits in visuospatial tasks. This proved particularly true for men, but the prediction was not borne out well for women. It led him to speculate that the abilities of the two hemispheres overlapped to an extent.

Electroencephalogram measurements have also shown a difference. When given abstract problems to work out, men showed a great deal of activity in the right side of their brain, while for women the activity was more generalised to both sides. Similar studies with teenage boys and girls gave similar results.

With women who had Turner’s syndrome, which comes about because they have only one X chromosome, XO, and are considered to behave in a very feminine manner, this diffusion of organisation was particularly marked. The phenomenon has also been found in men whose exposure to androgens in the womb was reduced.

Workers following hormonal hypotheses have found that in rats given testosterone at birth, the females developed a larger corpus callosum. Others have found that male rats showed a thicker right hemisphere, except when they were very old. One developmental theory is that high levels of prenatal testosterone slow neuron growth in left hemisphere.

However, Shute(4) analysed blood samples from groups of males and females whose hormones were within the normal range. For spatial tests, females with high androgen levels performed better than their lower androgen counterparts. However, low testosterone men performed better than high testosterone men, leading the researchers to conclude that high androgens may inhibit the acquisition of spatial skills, and that there may a low optimum level.

Other tests have claimed that females are superior in language, verbal fluency, speed of articulation and grammar, also arithmetic calculation. Their perceptual speed, for instance in matching items is better, and so is their manual precision. Males are reckoned to be better at tasks that are spatial in nature, such as maze performance and mental rotation tasks. Also mechanical skills, mathematical reasoning and finding their way through a route. Certainly, among brain injury patients, after damage to the left hemisphere, long term speech difficulties occur three times more often in males.

Some critics asked why, after a hundred years of research, these findings have only just appeared. One reason may be that most of the subjects studied originally were male war veterans. But, in any case, nobody had looked for sex differences. What we are discussing are average differences which are statistically significant but their effect is very small within a very wide range of individual variation. The investigator must be specifically looking for them, using a large number of subjects.

Anatomy.

Differences in brain anatomy have included the length of the left temporal plane, which is usually longer than the right. Of those showing a reversal, which was assumed to reflect a lesser degree of lateralisation, most were female. However, as Springer and Deutsch(5) warn us: “the link between anatomical asymmetries and functional hemispheres is an untested assumption.”

Cerebral blood flow is used as a measure of cerebral activation and, in a mental rotation task, women scored significantly lower. Both men and women showed greater right hemisphere activity, though with men it was greater in the right frontal lobe, and with women it was greater in the temporal-parietal region. Other differences have been found in other tasks, but there is no way of telling whether they are due to a difference in structural organisation, or simply the use of different strategies.

Some of the results are difficult to compare with others. For instance in recognising melodies and familiar sounds, women have had a left ear advantage, while in men, the difference was very small. Some workers have suggested that lateralisation for certain nonverbal auditory stimuli may be greater in women, rather than less.

Another problem is that the degree of lateralisation for auditory and visual tests do not always correlate for one individual. It may be that different individuals have different organisation for different tasks, or they are bringing in strategies that the experimenter didn’t intend, thus confounding the results. Repeating the tests at a later date, with the same subject, does not always produce the same result, as though on each occasion the problem has been approached in a slightly different way.

Unlearning learning.

We have seen how plastic cortical development is. Even with laboratory rats, it has been shown that those reared in a stimulating environment develop a much more intricate cerebral organisation than those reared in nothing more than a bare cage. Development is not either predicted by biology or learning.

Brain development goes on for many years after birth. It clearly must be influenced as much by the environment after birth as it was before. Exactly how and why, and by how much, is something that psychologists and biologists generally are very reticent to explore. They continue to work on independently following their separate paradigms, and do not cross the boundary. Psychologists use the general assumption that memory is composed of patterns of neuron firing. Biologists tend to work with permanent structures. It is thought that if a particular synapse is active often enough, it becomes more permanent, operating in preference to other possible synapses.

Others(6) have made suggestions based on the assumption that the degree of myelinisation of a particular area of the nervous system is a measure of its maturity – or, conversely, its loss of plasticity.

Clearly the social experience of a young baby is limited, but even then it is interacting, soaking up experience like a sponge. In an astonishingly short time it becomes proficient in a complicated, not entirely logical language. Even before an infant begins to talk, it understands sentences containing quite complex sequences.

Socialisation begins when it meets other children. In the days of the tribal group, this may have been from its first steps. In recent England, school began at five, and its primary experience would have been its parents, its siblings, relatives and visitors, perhaps next-door’s children.

The author has, from time to time, met counsellors, and other, who claim that transvestites can be cured. Gender reassignment is seen by a prejudiced National Health Service as elective cosmetic surgery. Gay people choose their way of life. Can anyone become other than who they really are? Something that is learned can be unlearned surely? Perhaps it is in reaction to such attitudes that certain groups of TV’s and others are so insistent about the biological model – otherwise they could ‘help’ being who they are.

It is assumed that much of one’s personality is learned, with an Eysenckian biological substrate, yet it is also assumed that any extensive personality change means trouble. It’s a question that psychology has not really addressed, perhaps developmental neurobiology will, one day, provide some answers, if it can, once and for all, free itself from political gender bias.

Conclusion.

Many critics have complained of the prevalence of what psychologists call the type 1 error in a number of these studies. That is, the differences are real when the results are actually due to chance. The problem is in extracting common features in a area where individual people vary greatly.

On balance, Springer and Deutsch(7) accept that there is a very small but consistent greater degree of lateralisation in male humans. They conclude “Our review of the lateralisation literature in general has given us a healthy respect for the type 1 error . . . . the consistency of reports of sex differences . . . . lead us to accept their reality, at least as a working hypothesis . . . . . there are true differences that are small in magnitude and easily masked by individual variability or other factors that are not controlled.”

Such differences as have been found have been labelled by most writers as differences in cognitive style. Given the difference in socialisation between girls and boys, it is hardly surprising that this occurs.

Witleson concluded that people use their ‘preferred cognitive strategy’ based on the faculties they have. It is suggested that men and women may tend to think in different ways, but every individual thinks in his, or her, individual way – each of us uses our preferred mental strategy. Let us not come to believe that all women think in one way and all men in the other.

Certainly, a study of adult male-to-female transsexuals found that they were better in verbal memory, and worse in mental rotation tasks than a control group of men. Groups of both male and female transsexuals groups also did not show a clear degree of lateralisation. Apart from the fact that, once again, they were possibly extreme cases, it does not necessarily show that their minds were ‘opposite sexed’ for biological reasons. It could just as well be argued that they acquired transsexual minds because of their conflict with the cultural criteria demanded of them.

The theory must be able to accommodate itself to allow for general differences, not stigmatising or clinicising those who do not conform. Men and women, perhaps, follow careers that utilise their individual abilities in the most satisfying and successful way. In spite of the predictions of biological determinism, there are female artists, designers, even mathematicians, and we are not short of male communicators.

As Sayers(8) says: “If boys are more able in Mathematics and girls have a greater verbal ability, it is hard to see how men can be better fitted for political life and their dominant role there.” What we have discovered should not be a prohibition against a man or a woman from entering a career normally viewed as being the province of the other gender, because of the way we suggest he, or she, ‘ought’ to think.

Afterword.

Throughout this chapter the difference between the cerebral hemispheres has been described as being between verbal versus spatial abilities, with a qualitative difference between women and men. Most workers believe this to be far too simple an idea. It may be that we are labelling the mental organisation in terms of the rather limited tests we are applying – we look for something, so we find it.

Considering the whole range of thought processes to which humans bring a whole range of strategies, it is possible that each problem that an individual’s brain attends to is unique, happening for the first time in human history.

What else can be said about the features of brain lateralisation? A more realistic way of describing the situation may be to suggest that each hemisphere approaches a task in a different way. Thus the left side may analyse the problem while the right considers it as a whole. This division has created a whole raft of hypotheses, such as rational vs intuitive, and western versus eastern thinking.

In turn there has been a rash of claims like “Unleash the power of your right brain. Send £50 for our five-day course.” Another is quizzes in popular journals which claim to test whether readers think like a man or a women. Naturally those completing the questionnaire already know how they ought to think, as men or women, and even know the ‘correct’ answers to the questions.

As one group of writers(9) suggest “hemispheric specialisation has become a sort of trash can for all sorts of mystical speculation.”

Nevertheless some insights have come from some more reputable sources. One needs to describe first the difference between conscious and automatic behaviours. Once we have learned to walk or ride a bicycle, we never forget. Current thinking is that such knowledge is transferred to the cerebellum. Probably, the automatic actions in manipulating the controls of a motor car are stored there also.

However, in our daily round we develop what are called action scripts, habitual procedures like making a cup of tea. If one goes to one’s bedroom to change for an outing and, instead, puts on one’s nightclothes and get into bed, it is the confusion of two action scripts. So, some workers believe that the right hemisphere handles processes for which there is an established routine, while the left side deals with novel situations. Perhaps the right brain handles more familiar tasks for which an action script is already available, while the left analytical side is better equipped to handle new situations.

This leads to an interesting speculation. We have all been cursed with the driver on the motorway, hogging the middle lane, operating on right side ‘autopilot’ mode, while his attentional left hemisphere is chatting to his passenger. If women have better communication between the hemispheres, perhaps they can switch control more easily, and they really are better drivers than men. Perhaps insurance companies should calculate premiums on the basis of brain scans taken while the person is performing a series of standardised tasks. Crazy, perhaps, but no more outlandish than the claims in some ‘pop’ psychology books.

Another hypothesis includes the function of the corpus callosum, which connects each side of the brain topographically – that is each fibre from a neuron in one side connects to its equivalent in the opposite side. This is described more fully in Springer and Deutsch,(10) but the idea is that an image in the left half, say a cow, inhibits the image in the right half, which allows it to conjure up associated images, like milk or a field.

Psychology students will be familiar with the words “Top down, bottom up,” but other speculations have included distinctions between analysis and insight, while another compares the right hemisphere to Freud’s seat of the unconscious

It has been suggested that, not only is the human brain more complex than we think, it is more complex than we can comprehend.

No doubt the debate about sex differences in general will continue ad nauseum. One study will suggest “the difference in size between the sexes has not escaped the notice of sociobiologists.” Another will point out that the size dimorphism in humans is less than for any other primate. It all depends on which side of the bread you like to spread your butter.

Bibliography and good reading.

  1. Fausto Sterling, A., (1992) Myths of Gender, Biological Theories about Women and Men, New York: Basic Books (bookshelf)
  2. Fausto Sterling, A., (1999) Sexing the Body: Gender Politics and the Construction of Sexuality, New York: Basic Books (bookshelf)
  3. Dekaban, A., (1978) Changes in Brain Weights during the span of Human Lives: relation of brain weights to body heights to body weights, Annals of Neurology 4(1978):345-56 in Fausto Sterling, A., (1992) Myths of Gender, Biological Theories about Women and Men, (p227) New York: Basic Books
  4. Springer, S.P., Deutsch, G., (1993) Left Brain Right Brain (Fourth ed. p215), New York: W.H.Freeman. (bookshelf)
  5. Springer, S.P., Deutsch, G.,
  6. Gibson, K.R., (1985) Myelinisation and Behavioural Development: A Comparative Perspective on Questions of Neoteny, Altricity and Intelligence, in Gibson, K.R., Petersen, A.C., Brain Maturation and Cognitive Development, New York: Aldine De Gruyter.
  7. Springer, S.P., Deutsch, G.,(p212),
  8. Sayers, J., (1982) Biological Politics, London: Tavistock
  9. Rose.S, Lewontin.R.C, Kamin.L.J, (1990) Not In Our Genes: Biology, Idealogy and Human Nature. (p146) Harmondsworth: Penguin Books. (bookshelf)
  10. Springer, S.P., Deutsch, G., (p299)

Taken from: http://www.gender.org.uk/about/07neur/77_diffs.htm

 

 

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