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Sunday, January 19, 2020
Friday, January 3, 2020
Unique experiment explores canine 'numerosity'
Date: December 18, 2019
Source: Emory Health Sciences
The results of a new canine numerosity study suggests that a common neural mechanism has been deeply conserved across mammalian evolution.
Biology Letters published the results, which suggest that a common neural mechanism has been deeply conserved across mammalian evolution.
"Our work not only shows that dogs use a similar part of their brain to process numbers of objects as humans do -- it shows that they don't need to be trained to do it," says Gregory Berns, Emory professor of psychology and senior author of the study.
"Understanding neural mechanisms -- both in humans and across species -- gives us insights into both how our brains evolved over time and how they function now," says co-author Stella Lourenco, an associate professor of psychology at Emory.
Such insights, Lourenco adds, may one day lead to practical applications such as treating brain abnormalities and improving artificial intelligence systems.
Lauren Aulet, a PhD candidate in Lourenco's lab, is first author of the study.
The study used functional magnetic resonance imaging (fMRI) to scan dogs' brains as they viewed varying numbers of dots flashed on a screen. The results showed that the dogs' parietotemporal cortex responded to differences in the number of the dots. The researchers held the total area of the dots constant, demonstrating that it was the number of the dots, not the size, that generated the response.
The approximate number system supports the ability to rapidly estimate a quantity of objects in a scene, such as the number of predators approaching or the amount of food available for foraging. Evidence suggests that humans primarily draw on their parietal cortex for this ability, which is present even in infancy.
This basic sensitivity to numerical information, known as numerosity, does not rely on symbolic thought or training and appears to be widespread throughout the animal kingdom. Much of the research in non-humans, however, has involved intensive training of the subjects.
Previous research, for example, has found that particular neurons in the parietal cortex of monkeys are attuned to numerical values. Such studies had not clarified whether numerosity is a spontaneous system in non-human primates, because the subjects underwent many trials and received rewards for selecting scenes with greater numbers of dots in preparation for the experiments.
Behavioral studies in dogs that were trained in the task of discriminating between different quantities of objects have also indicated that dogs are sensitive to numerosity.
The Emory researchers wanted to delve further into the neural underpinnings of canine number perception using fMRI.
Berns is founder of the Dog Project, which is researching evolutionary questions surrounding man's best, and oldest friend. The project was the first to train dogs to voluntarily enter an fMRI scanner and remain motionless during scanning, without restraint or sedation.
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Lourenco primarily researches human visual perception, cognition and development.
Eleven dogs of varying breeds were involved in the current fMRI experiments. The dogs did not receive advance training in numerosity. After entering the fMRI, they passively viewed dot arrays that varied in numerical value. Eight of the 11 dogs showed greater activation in the parietotemporal cortex when the ratio between alternating dot arrays was more dissimilar than when the numerical values were constant.
"We went right to the source, observing the dogs' brains, to get a direct understanding of what their neurons were doing when the dogs viewed varying quantities of dots," Aulet says. "That allowed us to bypass the weaknesses of previous behavioral studies of dogs and some other species."
Humans and dogs are separated by 80 million years of evolution, Berns notes. "Our results provide some of the strongest evidence yet that numerosity is a shared neural mechanism that goes back at least that far," he says.
Unlike dogs and other animals, humans are able to build on basic numerosity in order to do more complex math, drawing primarily on the prefrontal cortex. "Part of the reason that we are able to do calculus and algebra is because we have this fundamental ability for numerosity that we share with other animals," Aulet says. "I'm interested in learning how we evolved that higher math ability and how these skills develop over time in individuals, starting with basic numerosity in infancy."
Additional authors of the study include Veronica Chiu and Ashley Prichard, Emory graduate students in psychology, and Mark Spivak, CEO of Comprehensive Pet Therapy. Spivak and Berns co-founded Dog Star Technologies to develop techniques to study how dogs perceive the world.
The work was supported by the National Institutes of Health, the John Merck Fund and the Office of Naval Research.
Materials provided by Emory Health Sciences. Original written by Carol Clark. Note: Content may be edited for style and length.
Thursday, December 26, 2019
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Discovery creates the possibility scientists can someday develop treatments to curb impulsive eating
University of Georgia
A team of researchers has now identified a specific circuit in the brain that alters food impulsivity.
You're on a diet, but the aroma of popcorn in the movie theater lobby triggers a seemingly irresistible craving.
Within seconds, you've ordered a tub of the stuff and have eaten several handfuls.
Impulsivity, or responding without thinking about the consequences of an action, has been linked to excessive food intake, binge eating, weight gain and obesity, along with several psychiatric disorders including drug addiction and excessive gambling.
A team of researchers that includes a faculty member at the University of Georgia has now identified a specific circuit in the brain that alters food impulsivity, creating the possibility scientists can someday develop therapeutics to address overeating.
The team's findings were published recently in the journal Nature Communications.
"There's underlying physiology in your brain that is regulating your capacity to say no to (impulsive eating)," said Emily Noble, an assistant professor in the UGA College of Family and Consumer Sciences who served as lead author on the paper. "In experimental models, you can activate that circuitry and get a specific behavioral response."
Using a rat model, researchers focused on a subset of brain cells that produce a type of transmitter in the hypothalamus called melanin concentrating hormone (MCH).
While previous research has shown that elevating MCH levels in the brain can increase food intake, this study is the first to show that MCH also plays a role in impulsive behavior, Noble said.
"We found that when we activate the cells in the brain that produce MCH, animals become more impulsive in their behavior around food," Noble said.
To test impulsivity, researchers trained rats to press a lever to receive a "delicious, high-fat, high-sugar" pellet, Noble said. However, the rat had to wait 20 seconds between lever presses. If the rat pressed the lever too soon, it had to wait an additional 20 seconds.
Researchers then used advanced techniques to activate a specific MCH neural pathway from the hypothalamus to the hippocampus, a part of the brain involved with learning and memory function.
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Results indicated MCH doesn't affect how much the animals liked the food or how hard they were willing to work for the food. Rather, the circuit acted on the animals' inhibitory control, or their ability to stop themselves from trying to get the food."Activating this specific pathway of MCH neurons increased impulsive behavior without affecting normal eating for caloric need or motivation to consume delicious food," Noble said. "Understanding that this circuit, which selectively affects food impulsivity, exists opens the door to the possibility that one day we might be able to develop therapeutics for overeating that help people stick to a diet without reducing normal appetite or making delicious foods less delicious."
Wednesday, December 18, 2019
|Learn more about the astonishing human brain.|
Early-life exposure to dogs may lessen risk of developing schizophrenia
Findings do not link similar contact with cats to either schizophrenia or bipolar disorder
Johns Hopkins Medicine
And while Fido may help prevent that condition, the jury is still out on whether or not there's any link, positive or negative, between being raised with Fluffy the cat and later developing either schizophrenia or bipolar disorder.
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The study was largely supported by grants from the Stanley Medical Research Institute.
Saturday, December 14, 2019
By David Balog, Author of Healing the Brain: Stress, Trauma and LGBT/Q Youth
When he is interviewed by the media, Pete Buttigieg elicits strangely personal stories that reveal more about the author or interviewer than about the candidate. There's a lot of what I call "lightning rod" defensive talk. Buttigieg is a lightning rod for individual's feelings about gay rights, the gay community, their own sexuality. Rachel Maddow, in her first interview with Buttigieg, hemmed and hawed her way into discussing his relatively late coming out age. She was a bit too nosy and disrespectful when she asked him why it took him a decade longer than her to come out. It came across as an invasion of the man’s privacy. (The short of it: There is no prescribed time, no age factor for coming to terms with being gay.) Ms. Maddow is clearly more comfortable talking with more conventional candidates who appear on her show.
A wise commentator once said, "Permutations and combinations of self hatred...all minorities have them." Homophobia and self-homophobia are thriving in America and around the world. And what the media--straight and gay--doesn't get about Pete Buttigieg is that he does not conform to labels and preconceived ideas that have to do with being gay in America's heteronormative society. He has coped well with the reality of being gay and refuses to be stereotyped. He stands proudly with his husband, Chasten, and speaks his mid-western values. That he is not radical, angry, and loud puzzles the culture observers.
From the beginning of his campaign the progressive left media and gay media have derided Buttigieg, the first gay person with a legitimate shot at the presidency, as too conservative, too accommodating. Gay writers call him "not gay enough" or "the wrong type of gay." He says, to little avail, that he is not running to be the president of gay America, but the president of America. He wants to build or rebuild a Democratic coalition to win, one that reminds me of the FDR coalition that had a successful 50-year run. The coalition included Democratic party organizations, big city machines, labor unions , religious and ethnic identity groups-- Catholics, Jews and Blacks, liberal farm groups, intellectuals, and unfortunately, Southern segregationists.
More disturbingly, Buttigieg’s policy positions have been routinely misrepresented and distorted. CNN's Anderson Cooper chided Buttigieg in a Town Hall Event for not having a single policy plan on his Web site. From early on, Buttigieg has had detailed proposals and they were on his Web site. a secondary site. Too polite or not understanding Cooper's misstatement, Buttigieg moved on. He’s been assigned a spot in the ultra-white privileged class by a group called The Young Turks for his “fancy Ivy League” education. The Young Turks has relentlessly produced harsh videos about Buttigieg, with no corroboration from second-hand news organizations. He has been met by the soft bigotry of low expectations with commentators saying he's just way too young (age 37) and is angling just to get a cabinet appointment. Media figures like David Pakman, Sam Seder, and Cenk Uygar barely contain their contempt when discussing Buttigieg.
Michael Harriot, African-American author at the Root.com, shocked everybody recently by calling Buttigieg a “lying mother-fucker,” (an all-time low mark in political commentary) for words said eleven years ago on the lack of education equality for Blacks. Buttigieg was discussing only one aspect of the education system that has failed Blacks, the lack of role models to tell the story of the benefits of education. By not mentioning larger societal failures. Buttigieg was complicit in them, according to to Herriot.
Buttigieg has been credited by many with a revitalization of the city of South Bend, not a city of "elite privilege," in the shadow of Notre Dame University (which is not even within the city limits) but a struggling Midwest industrial city. If Michael Harriot has such low thoughts about Buttigieg, one must wonder what words the author would need to describe the current occupant of the White House.
One gay writer for the New Republic called Buttigieg "Mary Pete," a gay slur for his presumed lack of gay sexual experience and presumed sexual activities. (The story was immediately retracted by the New Republic.) Others instinctively focus on mainstream media tropes about his lack of support from the
African-American community, a story that is deeper and more complicated than a dated 0% showing in a South Carolina poll, a poll that is fluctuating in a primary for which campaigning has just begun.
Buttigieg does not deserve automatic support from the gay community, but neither does he deserve automatic disdain or character distortion.
As the late former Texas governor Ann Richards once said, politics can be a contact sport. If this was a boxing match, Buttigieg should have been declared loser by technical knockout in the early rounds.
But the Mayor is surviving the onslaught and is so far leading the field. He polls at the top in the key first two states, Iowa and New Hampshire, has raised a large amount of money, put in place a well-running national organization, offers policies and ideas that appeal to many, and by all accounts is incredibly intelligent, a fast thinker, and an effective communicator. He’s young, energetic, and has accomplished much in his short career.
So, how else to explain the unreasonableness and unfairness of his treatment?
Buttigieg upsets people by defying gay stereotypes.
Buttigieg upsets people by defying gay stereotypes.
Watching the “Only Bernie can fix it” messaging by the Young Turks, Hill TV, the Pakman show, and related others, can be deeply unsettling. It requires a willingness to suspend critical thinking and embrace a well-known message from the likes of Rush Limbaugh and Fox News: Don't think, listen to us only. We’ll give you the answers. Support the clear candidate of choice, Bernie Sanders, at the expense of all others.
One answer to the far-left messaging is the Dunning-Kruger effect, a cognitive bias in which people assess their own cognitive ability as greater than it is. It is related to the cognitive bias of illusory superiority and comes from the inability of people to recognize their own lack of ability. They think they have nothing to learn from anyone else, which produces an exceptionally arrogant and contemptuous manner. If you are already perfect, why would you ever listen to other people outside your limited political sphere?
Similarly, gay people can internalize their own homophobia as a survival tool and can direct their anger at each other. It's part of the set of toxic"survival" skills learned while hiding oneself in the closet.
Pete Buttigieg is different, special, highly intelligent...unlike the dull pudding of elected officials and pundrity controlling our current discourse. He answers questions in complete sentences and paragraphs so well constructed as to leave reporters with no tedious, time-filling, follow-up questions.
One way Buttigieg seems to have coped with his time alone in the closet, discovering and coming to terms with being gay, was to develop his innate substantial intellect. He read voraciously, became a skilled musician, and learned seven languages (another reason for ridicule by leftist media).
His delayed but now current openness about his sexual orientation confuses the pundits. He expresses a rare comfort about it; he does not focus on being gay, but he does not hide it or show anything but self-confidence. Buttigieg confounds everyone except audiences who hear his thoughtful, well-crafted, easy-to-understand speeches and answers. He talks neither above nor below audiences. It is no coincidence that his candidacy rose sharply in an extended interview format on a CNN Town Hall.
Buttigieg has been accused by his critics of benefiting from "white privilege" and the ability to hide, until age 33 when he "came out" of the ephemeral "closet." But the story of gay life in America is not simple.
Despite the the legalization of marriage equality in this country in 2015, homophobia and gay discrimination are still the de facto laws of the land.
Writing in “Public Health Implications of Same-Sex Marriage”, American Journal of Public Health 101, no. 6 (June 1, 2011), Dr. Bill Buffie debunks the idea that we live in a post-gay world of full equality.
"One only has to consider the rash of recent teen suicides resulting from anti-gay bullying to begin to comprehend the magnitude of the public health problem faced by this country and its LGBT sexual minority. Despite the prevalence of same-sex households and campaigns to protect human rights, gay persons find the very nature of their being constantly debated within our legislative bodies, the courts, and the mainstream media. They are subject to ridicule and are commonly the targets of demeaning and derogatory slang terms or insensitive jokes. Their morality and value as human beings are frequently questioned by individuals and organizations ignorant or unaccepting of current medical and social science literature concerning the gay population...."
"Being cast in such a light strongly contributes to the phenomenon known as 'minority stress,' which members of this community experience in their struggle for validation and acceptance in our heterosexist society.
"Unique to the LGBT form of minority stress—as opposed to minority stress engendered by societal prejudice based upon race, ethnicity, gender, or disability—is that one's sexual orientation usually is invisible to others. As a result, in addition to being the target of overt discrimination, LGBT individuals are constantly subject to subtle, inadvertent, or insensitive attacks on the core of their very nature, even by people who profess no disdain or disrespect for them."
Being a member of a marginalized group requires extra effort. Buttigieg has mastered coping with the stress.
Being a member of a marginalized group requires extra effort. Buttigieg has mastered coping with the stress.
Pete Buttigieg got punched the same ticket that 30 million or so LGBTQ Americans receive. He made the most he could of a situation that overwhelms many of us. Monied or not (and neither his parents or Buttigieg and his husband are particularly wealthy), privileged by education or not (and he earned his way into Harvard and Oxford), Buttigieg figured his way to cope and live well through a highly stigmatized social and deeply personal aspect of his life. Not only do gay people have to do a lot of extra emotional work and answer all these internal questions, we also have to do it utterly alone, without being able to talk to our friends or parents about it.
“The trauma for gay men is the prolonged nature of it,” says William Elder, a sexual trauma researcher and psychologist. “If you experience one traumatic event, you have the kind of PTSD that can be resolved in four to six months of therapy. But if you experience years and years of small stressors—little things where you think, "'Was that because of my sexuality?'—that can be even worse.”
In my work studying the brain and behavior, I learned one strong fact: constant stress greatly diminishes one's physical and emotional health. In his book "Why Zebras Don't Get Ulcers,” Dr. Robert Sapolsky documents that the stress hormone, cortisol, when activated over long periods, damages every part of our bodies. Cortisol is a steroid. It can shrink parts of our brain and diminish learning, reduce our immune system function, and stunt our normal growth.
Now that would seem to be indisputable science, but some would dispute it nonetheless. For example, some in the gay community would say that you need to take complete responsibility for your behavior. But can you act with free will when compromised by depression, substance abuse, and physical and emotional abuse? Hiding can be necessary in dangerous situations, but never succeeds emotionally. For example, how do you teach a five-year-old to reduce stress how to cope with the stress response from harsh homophobic language heard at home, at school, or on television?
Ironically, at the very place where I learned about stress, a private foundation in New York City, at least half of the staff of 30 people were lesbian or gay. Two presidents in a row, were gay men. But you dared not speak about the orientation that dare not speak its name. A woman who was the secretary or administrative assistant to the whole organization, to the president, deftly changed conversations if ever they came
close to feelings or experiences that I had that were related to anything to do with being gay. She was masterful at keeping conversation remote and distant when it involved the gay co-workers. So in the 1990s, and early 2000s, the gay staff spoke in code, carefully guarding any traces of our personal lives. For example, a co-worker’s weekend at a lesbian song festival became a few days in the Berkshires with friends. My participation in a groundbreaking gay hockey league, became just hockey with the boys, nothing more nothing less. A few of us saw the humor, saying while we may do research about stress, and cortisol, and we may write about it, we have oceans of it running through the hallways of the place we worked.
Which is why the popularity of Pete Buttigieg, at least in the early states, shows his remarkable ability to transcend stereotypes and misconceptions. Before large crowds in Iowa and New Hampshire he remarkably communicates his humanity, his personality, his hopes, his values to audiences on an equal level all without denying who he is. No matter what comes of his campaign, and I for one certainly hope that he succeeds and makes it to the White House, he has broken new ground and advanced the cause of gay rights tenfold with his historic campaign. For nothing else he needs to be admired and supported for this.
In his paper, Dr. Buffie describes a core concept that as a gay man Buttigieg must navigate.
"LGBT individuals, stigmatized by negative societal attitudes directed at the essence of their being, struggle on a daily basis to balance the dual dangers of publicly engaging their need for equality and validation and remaining closeted to find some calm through an escape from public scrutiny. Many gay persons internalize such discrimination and prejudice. Fractured social-support mechanisms and minority-stress–associated low self-esteem contribute to a high prevalence of self-destructive behaviors, such as substance abuse, suicide, and risky sexual behavior. Hatzenbuehler et al. studied more than 34,000 lesbian, gay, and bisexual participants and found empirical evidence of the negative health effects of discriminatory policies relative to marriage equality. They surveyed participants in 2001 and 2002 on a range of psychological health indicators, and they administered the same survey in 2004 and 2005, after 14 states approved constitutional amendments limiting marriage to opposite-sex unions. In the second set of responses, participants reported significantly higher rates of psychiatric disorders, with increases of 36% for any mood disorder, 248% for generalized anxiety disorder, 42% for alcohol use disorder, and 36% for psychiatric comorbidity. In the comparable control group from states without such amendments during the same time period, there were no significant increases in these psychiatric disorders.
"Although causality may be difficult to establish, the association and prevalence of these disorders suggest that institutionalized stigma and its attendant internalized prejudice (i.e., minority stress) stand at the forefront of this cycle, begetting higher rates of sexually transmitted diseases, depression, suicide, and drug use—all of which, when combined with suboptimal access to health care and fractured family-support systems, eventually contribute to higher overall mortality as well as morbidity from various cancers, cirrhosis, hypertension, and heart disease..."
That Pete Buttigieg confounds society's expectations and norms frustrates the punditocracy and distorts their interpretation of him. From afar they cannot grasp his growing popularity and rely on stale, preconceived ideas from elections and eras past. But as Buttigieg himself has said, despite the sharply divided country, technology, Americans’ attitudes and lives are changing rapidly. When a reporter asked him if he foresaw any problems dealing with nations that treat homosexuality harshly, Buttigieg replied confidently that "they will get used to it quickly."
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