recentpopularlog in

Quercki : brain   26

Is eating behavior manipulated by the gastrointestinal microbiota? Evolutionary pressures and potential mechanisms
Abstract

Microbes in the gastrointestinal tract are under selective pressure to manipulate host eating behavior to increase their fitness, sometimes at the expense of host fitness. Microbes may do this through two potential strategies: (i) generating cravings for foods that they specialize on or foods that suppress their competitors, or (ii) inducing dysphoria until we eat foods that enhance their fitness. We review several potential mechanisms for microbial control over eating behavior including microbial influence on reward and satiety pathways, production of toxins that alter mood, changes to receptors including taste receptors, and hijacking of the vagus nerve, the neural axis between the gut and the brain. We also review the evidence for alternative explanations for cravings and unhealthy eating behavior. Because microbiota are easily manipulatable by prebiotics, probiotics, antibiotics, fecal transplants, and dietary changes, altering our microbiota offers a tractable approach to otherwise intractable problems of obesity and unhealthy eating.
Keywords: cravings, evolutionary conflict, host manipulation, microbiome, microbiota, obesity
diet  health  mood  obesity  microbes  gut  brain 
8 weeks ago by Quercki
How to tell my wonderful 11 year old son, (in a way that won’t tear him down), that the way he has started talking to me (disrespectfully) makes me not want to be around him (I’ve already told him the bad attitude is unacceptable) - Quora
“See, the last part of your brain that gets rewritten is right at the front of your head. It’s called the frontal cortex. And that’s the part of your brain that’s good at decision making and understanding consequences. So you’ve got this powerful adult amygdala hitting you with massive emotions, but you’ve still got a fuzzy child frontal cortex that can’t make decisions or understand consequences as quickly as the amygdala wants you to. It pretty much sucks.”

“So it’s not my fault?”

“No, it’s puberty’s fault your brain works the way it does. But that doesn’t mean it’s not your responsibility to recognise what’s going on and change your actions. It’s not easy, but it’s not impossible, either. Your feelings are your feelings, and they’re always okay. But you get to choose your actions. You get to choose what you do with your feelings. And, when you make a mistake, you get to choose to apologise for that mistake and make amends.”

I paused for dramatic effect. “That’s how you prove that you’re becoming an adult.”
brain  growing  adolescent  11-year-old  boy  disrespect  talking 
december 2018 by Quercki
Every Single Cognitive Bias in One Infographic
WHAT IS A COGNITIVE BIAS?

Humans tend to think in certain ways that can lead to systematic deviations from making rational judgments.

These tendencies usually arise from:

Information processing shortcuts
The limited processing ability of the brain
Emotional and moral motivations
Distortions in storing and retrieving memories
Social influence
Cognitive biases have been studied for decades by academics in the fields of cognitive science, social psychology, and behavioral economics, but they are especially relevant in today’s information-packed world. They influence the way we think and act, and such irrational mental shortcuts can lead to all kinds of problems in entrepreneurship, investing, or management.
cognitive  bias  brain  thinking 
september 2017 by Quercki
Science Says Period Brains Aren't A Thing: Women Are Not Surprised - Our Bodies Ourselves
According to researchers in Switzerland and Germany who collected data on 88 women, there is “no consistent association between women’s hormone levels, in particular, estrogen and progesterone, and attention, working memory, and cognitive bias.”

The study included both healthy women and women with endocrine conditions, primarily endometriosis or polycystic ovary syndrome (PCOS). The women were given a series of neuropsychological tests so researchers could assess their visual memory, attention, and executive functions. Two things set this study apart from others on the topic: the sample size was larger than usual and the women were followed through two consecutive menstrual cycles. Researchers found no replicable data from the first cycle to the second; meaning, there were no universal changes to women’s thinking because of hormonal changes.
women  menstruation  brain 
july 2017 by Quercki
"Male brain" and "female brain": There's really not much of a difference.
Men and women are equal—and so are the architectures of our brains, according to a new study by neuroscientist Lise Eliot of the Rosalind Franklin University of Medicine and Science. According to a write-up in Wired, the study was aimed at evaluating the theory that the hippocampus is larger in women than in men; since the hippocampus is the part of the brain associated with memory and emotion, this has been proposed as an explanation for all those feelings ladies tend to have. Eliot and her team analyzed 6,000 MRI scans and found “no significant difference in hippocampal size between men and women.”

This is more than a matter of abstract interest for Eliot, the author of the 2010 book Pink Brain, Blue Brain, about how dubious theories of sex differences in the brain lead us to raise and educate boys and girls differently. She’s devoted years to decrying these kinds of stereotypes and their frustratingly strong grip on the American approach to childrearing. In 2011, she teamed up with other experts to write an article in the journal Science debunking the work of several same-sex education theorists, and in 2013, she debated conservative pundit Christina Hoff Sommers, author of a book that argues feminism initiated a “war on boys” in American schools.
male  brain  female  gender  science 
november 2015 by Quercki
Should We Believe Survivors? A Primer on the Neurobiology of Trauma — Everyday Feminism
As allies to survivors, we must believe that a survivor’s account of their sexual assault is true. We have absolutely nothing to lose by believing a survivor’s words, and a survivor has everything to gain through the experience of feeling trusted and validated.

Even if the details seem confusing, we must stand firm in knowing that their account of sexual assault is rooted in truth.

Even if we experience their account as disoriented, foggy, or even factually incorrect, we must understand that they are still telling their own deepest truth, and we must honor that.

When someone tells me that they were raped at noon on Tuesday and that the moon was shining and it was pitch black outside, I still believe them, even though I know that, objectively, the moon wasn’t shining at noon.

What I believe is that in that particular moment, their world felt as dark and quiet as the world seems at midnight.

I believe survivors. No matter what. So should you.

And here’s why: The brain literally changes size and shape as the result of a traumatic event. The way a person stores and shares what happened to them is fundamentally altered.
rape  trauma  brain 
january 2015 by Quercki
Males and Females Differ in Specific Brain Structures | LabRoots | Read Science News, Articles and Current Events
Specifically, males on average had larger volumes and higher tissue densities in the left amygdala, hippocampus, insular cortex, putamen; higher densities in the right VI lobe of the cerebellum and in the left claustrum; and larger volumes in the bilateral anterior parahippocampal gyri, posterior cingulate gyri, precuneus, temporal poles, and cerebellum, areas in the left posterior and anterior cingulate gyri, and in the right amygdala, hippocampus, and putamen.

By contrast, females on average had higher density in the left frontal pole, and larger volumes in the right frontal pole, inferior and middle frontal gyri, pars triangularis, planum temporale/parietal operculum, anterior cingulate gyrus, insular cortex, and Heschl's gyrus; bilateral thalami and precuneus; the left parahippocampal gyrus, and lateral occipital cortex.

The results highlight an asymmetric effect of sex on the developing brain. Amber Ruigrok, who carried out the study as part of her PhD, said: "For the first time we can look across the vast literature and confirm that brain size and structure are different in males and females. We should no longer ignore sex in neuroscience research, especially when investigating psychiatric conditions that are more prevalent in either males or females."
male  female  brain  sex  difference  science  research 
february 2014 by Quercki
You can increase your intelligence: 5 ways to maximize your cognitive potential | Guest Blog, Scientific American Blog Network
So—taking all of this into account, I have come up with five primary elements involved in increasing your fluid intelligence, or cognitive ability. Like I said, it would be impractical to constantly practice the dual n-back task or variations thereof every day for the rest of your life to reap cognitive benefits. But it isn’t impractical to adopt lifestyle changes that will have the same—and even greater cognitive benefits. These can be implemented every day, to get you the benefits of intense entire-brain training, and should transfer to gains in overall cognitive functioning as well.

These five primary principles are:

1. Seek Novelty

2. Challenge Yourself

3. Think Creatively

4. Do Things The Hard Way

5. Network
brain  howto 
october 2013 by Quercki
Obesity phenotypes in midlife and cognition in ear... [Neurology. 2012] - PubMed - NCBI
RESULTS:
Of the participants, 31.0% had metabolic abnormalities, 52.7% were normal weight, 38.2% were overweight, and 9.1% were obese. Among the obese, the global cognitive score at baseline (p = 0.82) and decline (p = 0.19) over 10 years was similar in the metabolically normal and abnormal groups. In the metabolically normal group, the 10-year decline in the global cognitive score was similar (p for trend = 0.36) in the normal weight (-0.40; 95% confidence interval [CI] -0.42 to -0.38), overweight (-0.42; 95% CI -0.45 to -0.39), and obese (-0.42; 95% CI -0.50 to -0.34) groups. However, in the metabolically abnormal group, the decline on the global score was faster among obese (-0.49; 95% CI -0.55 to -0.42) than among normal weight individuals (-0.42; 95% CI -0.50 to -0.34), (p = 0.03).
CONCLUSIONS:
In these analyses the fastest cognitive decline was observed in those with both obesity and metabolic abnormality.
cholesterol  mental  diabetes  hypertension  brain 
september 2012 by Quercki
How Your Cat Is Making You Crazy - Magazine - The Atlantic
Starting in the early 1990s, he began to suspect that a single-celled parasite in the protozoan family was subtly manipulating his personality, causing him to behave in strange, often self-destructive ways. And if it was messing with his mind, he reasoned, it was probably doing the same to others.

The parasite, which is excreted by cats in their feces, is called Toxoplasma gondii (T. gondii or Toxo for short) and is the microbe that causes toxoplasmosis—the reason pregnant women are told to avoid cats’ litter boxes. Since the 1920s, doctors have recognized that a woman who becomes infected during pregnancy can transmit the disease to the fetus, in some cases resulting in severe brain damage or death. T. gondii is also a major threat to people with weakened immunity: in the early days of the AIDS epidemic, before good antiretroviral drugs were developed, it was to blame for the dementia that afflicted many patients at the disease’s end stage. Healthy children and adults, however, usually experience nothing worse than brief flu-like symptoms before quickly fighting off the protozoan, which thereafter lies dormant inside brain cells—or at least that’s the standard medical wisdom.

But if Flegr is right, the “latent” parasite may be quietly tweaking the connections between our neurons, changing our response to frightening situations, our trust in others, how outgoing we are, and even our preference for certain scents. And that’s not all. He also believes that the organism contributes to car crashes, suicides, and mental disorders such as schizophrenia. When you add up all the different ways it can harm us, says Flegr, “Toxoplasma might even kill as many people as malaria, or at least a million people a year.”
cats  parasites  brain  science  mental 
february 2012 by Quercki
The Creative Brain On Exercise | Fast Company
As Dr. John Ratey noted in his seminal work Spark: The Revolutionary New Science of Exercise and the Brain (2008), exercise isn't just about physical health and appearance. It also has a profound effect on your brain chemistry, physiology, and neuroplasticity (the ability of the brain to literally rewire itself). It affects not only your ability to think, create, and solve, but your mood and ability to lean into uncertainty, risk, judgment, and anxiety in a substantial, measurable way, even though until very recently it's been consistently cast out as the therapeutic bastard child in lists of commonly accepted treatments for anxiety and depression.
In 2004 the esteemed New England Journal of Medicine (NEJM) published a review of treatments for generalized anxiety disorder that noted thirteen pharmaceuticals, each with a laundry list of side effects, but nothing about exercise. In response, NEJM published a letter by renowned cardiologists Richard Milani and Carl Lavie, who had written more than seventy papers on the effect of exercise on the heart, eleven of them focused on anxiety. That letter criticizes the original article for omitting exercise, which, the writers note, "has been shown to lead to reductions of more than 50 percent in the prevalence of the symptoms of anxiety. This supports exercise training as an additional method to reduce chronic anxiety."
anxiety  brain  exercise  creativity 
october 2011 by Quercki
Your Brain on Politics: The Cognitive Neuroscience of Liberals and Conservatives | The Intersection | Discover Magazine
Can neuroscience provide evidence for a liberal and conservative thinking style?
It may seem like a stretch to say that one could predict whether you lean left or right by looking at a brain scan—no questions asked, no opinions voiced—purely based on your neuroanatomy. However, this might not be too far from reality—at least insofar as predicting thinking style, which has been shown to be somewhat distinct based on party association.
Does brain structure determine your beliefs, or do your beliefs change your brain structure? What about those who switch parties at some point? How do they fit in to this model? We’ll be discussing all of this. It’s a complicated issue with lots of variables in play, so we’re going to take a pretty deep look into this topic from all angles, so we can draw the most accurate conclusions.
Please keep in mind from the beginning that this is not an endorsement of any one political party. This is science—we’ll just be discussing the data. Ready?
neuroscience  politics  brain  conservative 
september 2011 by Quercki
Complex and Hidden Brain in Gut Makes Stomachaches and Butterflies - New York Times
Details of how the enteric nervous system mirrors the central nervous system have been emerging in recent years, said Dr. Gershon, who is considered one of the founders of a new field of medicine called neurogastroenterology.

Nearly every substance that helps run and control the brain has turned up in the gut, Dr. Gershon said. Major neurotransmitters like serotonin, dopamine, glutamate, norepinephrine and nitric oxide are there. Two dozen small brain proteins, called neuropeptides, are in the gut, as are major cells of the immune system. Enkephalins, one class of the body's natural opiates, are in the gut. And in a finding that stumps researchers, the gut is a rich source of benzodiazepines -- the family of psychoactive chemicals that includes such ever popular drugs as Valium and Xanax.

In evolutionary terms, it makes sense that the body has two brains, said Dr. David Wingate, a professor of gastrointestinal science at the University of London and a consultant at Royal London Hospital. The first nervous systems were in tubular animals that stuck to rocks and waited for food to pass by, Dr. Wingate said. The limbic system is often referred to as the "reptile brain."

As life evolved, animals needed a more complex brain for finding food and sex and so developed a central nervous system. But the gut's nervous system was too important to put inside the newborn head with long connections going down to the body, Dr. Wingate said. Offspring need to eat and digest food at birth. Therefore, nature seems to have preserved the enteric nervous system as an independent circuit inside higher animals. It is only loosely connected to the central nervous system and can mostly function alone, without instructions from topside.
gut  brain  bacteria  neuroscience 
may 2011 by Quercki
The Neuroscience of the Gut: Scientific American
Consistent with these behavioral findings, two genes implicated in anxiety -- nerve growth factor-inducible clone A (NGF1-A) and brain-derived neurotrophic factor (BDNF) -- were found to be down-regulated in multiple brain regions in the germ-free animals. These changes in behavior were also accompanied by changes in the levels of several neurotransmitters, chemicals which are responsible for signal transmission between nerve cells. The neurotransmitters dopamine, serotonin and noradrenaline were elevated in a specific region of the brain, the striatum, which is associated with the planning and coordination of movement and which is activated by novel stimuli, while there were there were no such effects on neurotransmitters in other brain regions, such as those involved in memory (the hippocampus) or executive function (the frontal cortex).

When Pettersson’s team performed a comprehensive gene expression analysis of five different brain regions, they found nearly 40 genes that were affected by the presence of gut bacteria.
brain  science  bacteria 
april 2011 by Quercki
The Neuroscience of the Gut: Scientific American
Princeton University scientist Bonnie Bassler compared the approximately 30,000 human genes found in the average human to the more than 3 million bacterial genes inhabiting us, concluding that we are at most one percent human. We are only beginning to understand the sort of impact our bacterial passengers have on our daily lives.
...
The scientists raised mice lacking normal gut microflora, then compared their behavior, brain chemistry and brain development to mice having normal gut bacteria. The microbe-free animals were more active and, in specific behavioral tests, were less anxious than microbe-colonized mice.
brain  science  bacteria 
april 2011 by Quercki
2 Distinct Circuits in the Brain Believed Involved in Doing Math / One for exact calculations, one for rough estimates
The ability to do mathematics -- everything from simple arithmetic to thinking up equations that explain an expanding universe -- may stem from the interaction of two brain circuits that handle numbers differently, two scientists have found.
In a series of experiments involving bilingual college students, the researchers discovered that one circuit gives names to numbers and carries out exact calculations. A second circuit operates intuitively and is used for estimating quantities and other numerical relationships.

Dr. Stanislas Dehaene, a neuroscientist at the National Institute for Health and Medical Research (known as Inserm) in Orsay, France, and Dr. Elizabeth Spelke, a cognitive psychologist at the Massachusetts Institute of Technology in Cambridge, Mass., described the results of their study in last week's issue of Science magazine.
math  brain 
december 2010 by Quercki
How Prozac sent the science of depression in the wrong direction - The Boston Globe
It is jarring to think of depression in terms of atrophied brain cells, rather than an altered emotional state. It is called "depression," after all. Yet these scientists argue that the name conceals the fundamental nature of the illness, in which the building blocks of the brain - neurons - start to crumble. This leads, over time, to the shrinking of certain brain structures, like the hippocampus, which the brain needs to function normally.
depression  brain  exercise 
october 2010 by Quercki
Why Music Moves Us: Scientific American
Some scientists conclude that music’s influence may be a chance event, arising from its ability to hijack brain systems built for other purposes such as language, emotion and movement. As Harvard University psychologist Steven Pinker famously put it in his 1997 book How the Mind Works (W. W. Norton), music is “auditory cheesecake,” a confection crafted to tickle the areas of the mind that evolved for more important functions. But as a result of that serendipity, music seems to offer a novel system of communication rooted in emotions rather than in meaning. Recent data show, for example, that music reliably conveys certain sentiments: what we feel when we hear a piece of music is remarkably similar to what everybody else in the room is experiencing.
music  psychology  science  brain  research  cognition  neuroscience  mind 
july 2009 by Quercki
Language Log: David Brooks, Neuroendocrinologist with links to other articles about sex differences
In my opinion, the most important insight in this area right now is Deena Skolnick's demonstration of the power of neuroscience to cloud people's minds. She took explanations of psychological phenomena that had been crafted to be "awful", and which (in their plain form) were recognized as bad both by novices and by experts, and added some (totally irrelevant) sentences about brain anatomy and physiology. With the added neuroscientific distraction, the bad explanations were perceived as satisfactory ones. [Update 6/6/2007: the paper has now been published, and is discussed here. ]
brain  gender  language  statistics  women 
january 2009 by Quercki

Copy this bookmark:





to read