Monday, May 12, 2008

Mind & Brain - Trauma Memories, Anxiety, Depression, Substance Abuse, and More

All kinds of interesting items on the mind & brain to report today. As always, these are excerpts of longer articles, so follow the links to read the whole article.

From Psychology Today: Love's Loopy Logic

A date makes us both spectator and performer at a two-ring circus: We troll for wit, kindness, curiosity, and "chemistry," hoping that we radiate these same attributes in the right amounts. From strategic winks and blinks to elaborate grooming to gifts of gorgeous baubles, men and women employ an arsenal of tricks in their romantic lives, all in the service of a demanding master at the far reaches of conscious awareness. Eons of evolution have honed our behavior to aid and abet a reproductive payoff. The sum of the stratagems we employ, and the wisdom of nature in crafting them without our explicit awareness, are now the subject of intense study by evolutionary psychologists.

Our sexual calculations and character reconnaissance, it turns out, call for smart, but not always accurate, judgments. That's because mating intelligence is as oxymoronic as the term suggests. We routinely bring both cold reason and outsized misconceptions to a relationship. Both serve a purpose. A woman will accurately gauge her date's personality on first meeting, but she will grow more convinced of his good humor and charm if they stick together. To woo a woman, a guy will grossly exaggerate his income, commitment, and affection for cuddly creatures. But he may have to correctly read microgestures as fine as tea leaves to discern whether she's truly impressed.

Male and female mating intelligence part ways when it comes to each sex's competing procreative goals. Inscrutable though our machinations may be to our partners (and to ourselves), romantic behavior is driven by a deep logic. Our minds have evolved to warp reality. Even so, we have unique skews in the mating realm. We've all got blind spots about the opposite sex. And sometimes that's for the best.

This is a long, but interesting article.

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From Science Daily: Why Emotional Memories Of Traumatic Life Events Are So Persistent

The expression “post-traumatic stress disorder” is once again constantly on everyone’s lips in relation to those returning from the Iraq war or survivors of catastrophes such as the tsunami. This is not a new development, since it always occurs when people experience extreme situations. It is known that emotional memories of both a positive and a negative kind are stored by our brain in a particularly robust way.

Consequently they have a very large effect on our behaviour and, in the case of adverse memories, they can place considerable restrictions on the way we go about our lives. As a result, we avoid places, smells or objects that remind us of the traumatic experience, because they may trigger severe anxieties. Isabelle Mansuy, Professor of Cellular Neurobiology at ETH Zurich and of Molecular and Cognitive Neurosciences at the University of Zurich, and her research group have now shown that the enzyme calcineurin and the gene regulation factor Zif268 decisively determine the intensity of emotional memories. For the first time, this has enabled the regulatory processes at the synapse, which are important for emotional memories, to be linked to the processes in the cell nucleus.

This might finally allow for an effective treatment for PTSD and other trauma related issues. Other approaches, such as EMDR, have also proven successful - and they might work by disrupting memory storage at the cellular level and allowing the emotions to be processed in the therapeutic setting.

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Again, from Science Daily: Are Anxiety Disorders All In The Mind?

The study compared densities of elements of the serotonin and dopamine neurotransmitter systems in the brains of 12 people diagnosed with social anxiety disorder, but who had not taken medication to treat it, and a control group of 12 healthy people who were matched by sex and age.

Both groups were injected with a radioactive compound that binds with elements of the brain's serotonin and dopamine systems. Once administered, the radiotracer revealed functional alterations in these systems by measuring the radioactive binding in the thalamus, midbrain and pons (known to be acted upon by serotonin) and in the striatum (known to be acted upon by dopamine). The altered uptake activity in these regions indicated a greater level of disordered function.

"Our study provides direct evidence for the involvement of the brain's dopaminergic system in social anxiety disorder in patients who had no prior exposure to medication," said Dr. van der Wee, M.D., Ph.D., at the department of psychiatry and the Leiden Institute for Brain and Cognition at the Leiden University Medical Center, Leiden (and previously at the Rudolf Magnus Institute of Neuroscience, University Medical Center in Utrecht, The Netherlands). "It demonstrates that social anxiety has a physical, brain dependent component."

Those of us with social anxiety who have tried all the various non-drug approaches already knew it had a biological basis.

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One more from Science Daily: Young People Are Intentionally Drinking And Taking Drugs For Better Sex, European Survey Finds

The study was conducted by researchers in public health and social sciences from across Europe. More than 1300 people aged between 16 and 35 and who routinely socialise in nightlife settings completed anonymous questionnaires.

Virtually all of the survey participants had drunk alcohol with most having had their first drink when 14 or 15 years old. Three quarters of the respondents had tried or used cannabis, while around 30 percent had at least tried ecstasy or cocaine.

Overall, alcohol was most likely to be used to facilitate a sexual encounter, while cocaine and cannabis were more likely to be utilised to enhance sexual sensations and arousal.

Despite these perceived sexual "benefits", drunkenness and drug use were strongly associated with an increase in risk taking behaviour and feeling regretful about having sex while under the influence of alcohol or drugs. Thus, participants who had been drunk in the past four weeks were more likely to have had five or more partners, sex without a condom and to have regretted sex after drink or drugs in the past 12 months. Cannabis, cocaine or ecstasy use was linked to similar consequences.

[Emphasis added.] Is anyone surprised by these findings? These people are probably going to end up in some form of treatment at some point. At least I hope so (and I can say that because I have been where they are now).

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From Medical News Today: Untreated Depressed People Have Fewer Serotonin & Opioid Receptors, And Variation Is Linked To Symptoms And Treatment Response
Depressed people may have far fewer of the receptors for some of the brain's "feel good" stress-response chemicals than non-depressed people, new University of Michigan Depression Center research shows.

And even among depressed people, the numbers of these receptors can vary greatly. What's more, the number of receptors a depressed person has appears to be linked with the severity of their symptoms - and the chances that they'll feel better after taking a medication.

These preliminary findings, presented at the American Psychiatric Association's annual meeting in Washington, D.C., amplify a growing understanding of depression as a condition that affects different people in different ways, and is solidly rooted in genetic and molecular factors that are unique to each individual.
Yep.

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From EurekAlert, more on substance abuse: Men are more likely than women to crave alcohol when they feel negative emotions

Women and men tend to have different types of stress-related psychological disorders. Women have greater rates of depression and some types of anxiety disorders than men, while men have greater rates of alcohol-use disorders than women. A new study of emotional and alcohol-craving responses to stress has found that when men become upset, they are more likely than women to want alcohol.

Results will be published in the July issue of Alcoholism: Clinical & Experimental Research and are currently available at OnlineEarly.

“We know that women and men respond to stress differently,” said Tara M. Chaplin, associate research scientist at Yale University School of Medicine and first author of the study. “For example, following a stressful experience, women are more likely than men to say that they feel sad or anxious, which may lead to risk for depression and anxiety disorders. Some studies have found that men are more likely to drink alcohol following stress than women. If this becomes a pattern, it could lead to alcohol-use disorders.”

As part of a larger study, the researchers exposed 54 healthy adult social drinkers (27 women, 27 men) to three types of imagery scripts – stressful, alcohol-related, and neutral/relaxing – in separate sessions, on separate days and in random order. Chaplin and her colleagues then assessed participants’ subjective emotions, behavioral/bodily responses, cardiovascular arousal as indicated by heart rate and blood pressure, and self-reported alcohol craving.

“After listening to the stressful story, women reported more sadness and anxiety than men,” said Chaplin, “as well as greater behavioral arousal. But, for the men … emotional arousal was linked to increases in alcohol craving. In other words, when men are upset, they are more likely to want alcohol.”

Again, is anyone surprised by these findings? Traditionally, men have not been taught how to sit with "hard" feelings, only that they aren't supposed to show them. So what do they do? They make them go away any way they can. Been there, done that.

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Finally, from The Daily Mail: The REAL brain drain: Modern technology - including violent video games - is changing the way our brains work, says neuroscientist

What would such aspirations to be "perfect" or "better" do to our notions of identity, and what would it do to those who could not get their hands on the pills? Would some finally have become more equal than others, as George Orwell always feared?

Of course, there are benefits from technical progress - but there are great dangers as well, and I believe that we are seeing some of those today.

I'm a neuroscientist and my day-to-day research at Oxford University strives for an ever greater understanding - and therefore maybe, one day, a cure - for Alzheimer's disease.

But one vital fact I have learnt is that the brain is not the unchanging organ that we might imagine.

It not only goes on developing, changing and, in some tragic cases, eventually deteriorating with age, it is also substantially shaped by what we do to it and by the experience of daily life.

When I say "shaped", I'm not talking figuratively or metaphorically; I'm talking literally.

At a microcellular level, the infinitely complex network of nerve cells that make up the constituent parts of the brain actually change in response to certain experiences and stimuli.

The brain, in other words, is malleable - not just in early childhood but right up to early adulthood, and, in certain instances, beyond.

The surrounding environment has a huge impact both on the way our brains develop and how that brain is transformed into a unique human mind.

Of course, there's nothing new about that: human brains have been changing, adapting and developing in response to outside stimuli for centuries.

What prompted me to write my book is that the pace of change in the outside environment and in the development of new technologies has increased dramatically.

This will affect our brains over the next 100 years in ways we might never have imagined.

Our brains are under the influence of an ever- expanding world of new technology: multichannel television, video games, MP3 players, the internet, wireless networks, Bluetooth links - the list goes on and on.

One of the central premises of Clare Graves's theory -- that became Spiral Dynamics -- is that the life conditions individuals face (environment) have a marked impact on brain chemistry and evolution. This article supports that once-rejected point of view. The evolution of neurostructures can occur within a single generation, and the fact that we are messing with these chemicals and structures both directly and indirectly might have profound implications for our future as a species.


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