Tag: medicine

Animals can lie to themselves too

Like Humans, Crayfish Talk a Tough Game

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Self-deception like this seems very human. Now, thanks to a recent study led by an Arizona State University biologist, for the first time we know that it happens in the animal kingdom, too.

Crayfish are some of the most aggressive creatures on earth. They fight with big claws capable of doing real damage. But sometimes there’s not much muscle under the bravado.

“What males are doing is making as little crappy muscle as possible, which is energetically saving,” said Michael Angilletta, a biology professor in the School of Life Sciences.

It’s like buying designer knockoffs. You save a lot of money, and most people can’t tell the difference. In the case of crayfish, you make a big claw without much muscle, and you put crappy muscle on it to boot. Everyone sees you wave your big claw and they presume that you’re a powerful crayfish.

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“Since they signal to each other before fighting, this is a way they can convince someone to back down without fighting,” Angilletta said. “Importantly, this only works if there’s enough crayfish out there that have big claws that are actually strong. If you accidentally fight one of those and call a bluff, you’re going to lose a claw.”

In the crayfish world, losing a claw is a disaster: It takes up to two years for a claw to regenerate. In the meantime, no one is mating with anyone who has a puny claw. 

Angilletta and his co-authors have been studying self-deception in crayfish for about 10 years. In 2006 they accidentally discovered that many crayfish with big claws were quite weak. There was about a tenfold variation.

“You would go, ‘Oh, this (pinch) is going to hurt,’ but it doesn’t hurt at all,” Angilletta said. “The question is are they not trying, or are they really not strong? And it’s repeatable from day after day with the same individuals.”

They combined mathematical modeling with an experiment to show that crayfish meet the criteria for self-deception. This approach opens up the possibility of studying self-deception in nonhuman animals, without being able to talk to them. They used 97 adult males, staging fights between 20 select crayfish and 77 opponents.

“How do we know what a crayfish would do if it knows whether it’s weak or it’s strong?” Angilletta asked. “If it knows that (it has a weak claw), it should actually be less aggressive.”

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It might escalate up to the point of a fight, and then run away. The probability that a crayfish engaged in a fight depended on two factors: the relative size of its claws and the expected difference in force. How do they know how strong (or not) they are? Crayfish use claws to deter predators, defend territory and capture prey. They have a pretty good idea of how strong their own claws are. They’re also skilled at assessing their size versus an opponent’s. They can even recognize previous opponents.

So natural selection has given them an ability to detect size and identity. Given that they have those abilities, it naturally follows that they have an ability to gauge strength when knowing it will improve decisions.

“In our population of crayfish, deceptive signalers largely ignored their own strength when escalating or evading aggression,” Angilletta said. “If this benefit of heightened aggression outweighs any long-term cost, natural selection should favor individuals who escalate aggression through self-deception.”

In other words, they buy into their own bluff. Angilletta teaches a biology course on human behavior called “Why people steal, cheat, and lie,” which explores the ecological and evolutionary causes of selfishness and cooperation in human societies.

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“What’s new about this study is that if you’re ever in a situation where I’m lying to you, there’s also a possibility I’m selling my lie exceptionally well because I’ve convinced myself that it’s true,” he said. “That’s because of self-deception. It’s very common in psychology but it’s not really that much in biology because we’re usually thinking about nonhuman animals and we don’t know what they’re thinking. We have a hard time understanding what they know and don’t know.”

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The paper was published last summer in Behavioral Ecology.

Video Credits:  Ken Fagan, ASU

Photo Credit: Charlie Leight, ASU

About ASU

Arizona State University has developed a new model for the American Research University, creating an institution that is committed to access, excellence and impact. ASU measures itself by those it includes, not by those it excludes. As the prototype for a New American University, ASU pursues research that contributes to the public good, and ASU assumes major responsibility for the economic, social and cultural vitality of the communities that surround it.

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Medicinal Cannabis Research

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Researchers will look at how CBD might help remedy schizophrenia, rheumatoid arthritis, insomnia, alcohol dependence and anorexia anxiety

The Center for Medicinal Cannabis Research (CMCR) at University of California San Diego School of Medicine, the nation’s oldest research center for scientific inquiry into the safety and efficacy of cannabis, has announced $3 million in research grants to explore new applications of cannabis for a number of novel medical applications.

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The cannabis plant produces a number of compounds called cannabinoids, the most widely known of which are tetrahydrocannabinol (THC), its principle psychoactive agent, and cannabidiol (CBD), which has been linked to reduced pain, anxiety and inflammation in previous studies. The five new studies all focus on CBD.

“Within the medical community, there is a lot of interest in the role of medical cannabis and CBD,” said Igor Grant, MD, Distinguished Professor in the Department of Psychiatry and CMCR director. “There is a hope that it could be yet another useful agent in some of these conditions, which are difficult to treat or disabling.”

The five grants are funded by California Proposition 64, which was passed on the November 8, 2016 ballot and legalized recreational marijuana in the state. The measure allocated tax revenue for research on potential new drugs, treatment and health and safety programs related to marijuana and medical cannabis.

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This year marks CMCR’s first such funding. All five grants are for proof-of-principle studies that would seek to establish the basis for future research.

Effects of Cannabidiol versus Placebo as an Adjunct to Treatment in Early Psychosis

The $825,000 grant was awarded to Kristin Cadenhead, MD, professor of psychiatry at UC San Diego School of Medicine, and colleagues, who will explore whether medical cannabis could serve as an alternative treatment for patients facing early psychosis, a time when traditional treatments, such as antipsychotic medications, are moderately effective but produce debilitating side effects.

Therapeutic Response of Cannabidiol in Rheumatoid Arthritis

The $825,000 grant was awarded to Veena Ranganath, MD, a rheumatologist at UCLA Medical Center. Ranganath’s research focuses on CBD’s use an anti-inflammatory agent, an application she hopes to exploit in treating rheumatoid arthritis, a chronic autoimmune condition that affects an estimated 1.5 million persons in the United States.

Cannabidol for Sedative/Hypnotic-sparing Management of Insomnia in Adults

The $825,000 grant was awarded to Mariana Cherner, PhD, professor of psychiatry at UC San Diego School of Medicine, and colleagues, who will investigate whether CBD might be a viable alternative for sleeping pills among patients with chronic sleep disorders.

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“Sleeping pills are moderately safe but they can also be habit-forming and they do have side effects, particularly in older people,” said Grant. “So many people are prescribed sleeping pills so there’s good reason to look for something that might be safer and not have that side effect profile.”

Cannabidiol as a Strategy to Treat Alcohol Dependence

The $300,000 grant was awarded to Giordano de Guglielmo, PhD, assistant adjunct professor in the UC San Diego Skaggs School of Pharmacy and Pharmaceutical Sciences, and colleagues. This study is the only one of the five using an animal model. It will look at the role CBD might play in reducing alcohol cravings and withdrawal syndromes among alcohol-addicted rats, with findings perhaps applicable to future human research.

The Role of Cannabidiol in Regulating Meal Time Anxiety in Anorexia Nervosa

The $300,000 grant was awarded to Emily Gray, MD, associate clinical professor of psychology at UC San Diego School of Medicine, and colleagues, who will explore whether CBD can help reduce a core symptom of anorexia — anxiety about food — and whether or not that reduction helps patients also reduce their food aversions overall.

A second round of CMCR grants is scheduled for 2020.

Sweating People

Photo by Food Photographer | Jennifer Pallian

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When people become stressed, their bodies can respond by sweating. Now, researchers at the University of Missouri are monitoring how much adolescents severely affected by autism sweat in order to better understand when behavioral issues, such as aggression, are likely to occur.

Bradley Ferguson analyzed the stress levels of eight adolescents who are severely affected by autism spectrum disorder at The Center for Discovery, a residential facility in New York that provides advanced care and research for individuals with complex conditions. Using wrist and ankle monitors, Ferguson found that there was a rise in the body’s electrodermal activity – which results from increased levels of sweat – 60% of the time before an individual showed behavioral issues.

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“A spike in electrodermal activity is telling us that the individual’s body is reacting physiologically to something that is stressful, which could be their internal state, something in the environment, or a combination of the two,” said Ferguson, assistant research professor in the departments of health psychology, radiology and the Thompson Center for Autism and Neurodevelopmental Disorders. “If parents or caregivers are notified ahead of time that their child’s stress levels are rising, they might have a chance to intervene and de-escalate the situation before problem behaviors occur.”

Ferguson explained that possible intervention methods could include removing the child from the environment or activity that is causing the stress, as well as providing access to an item that the child enjoys interacting with in an effort to calm them.

“Individuals who are severely affected by autism spectrum disorder are often unable to verbally communicate their discomfort when they become stressed,” Ferguson said. “However, their body still responds to stressors just like anyone else. Therefore, being alerted of increases in electrodermal activity can allow parents and caregivers to intervene prior to engagement in problem behavior with the goal of ensuring the health and safety of those involved.”

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Ferguson collaborated on the study with David Beversdorf, a professor of radiology, neurology and psychology in the MU College of Arts and Science as well as principal investigator of the Cognitive Neuroscience Laboratory in the MU School of Medicine. Ferguson also collaborated with Theresa Hamlin, Johanna Lantz, and Tania Villavicencio at The Center for Discovery, and John Coles at Calspan-University of Buffalo Research Center and The State University of New York at Buffalo.

“Important work is being done to try to identify predictors for when a person with autism is at greatest risk of having a behavioral episode,” Beversdorf said. “This research highlights the individual variability in this response that must be considered, and may also have implications for individualized treatment approaches moving forward.”

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“Examining the association between electrodermal activity and problem behavior in severe autism spectrum disorder: A feasibility study,” was published in Frontiers in Psychiatry.

The study was funded by the New York State Center of Excellence, New York State Department of Health and Office for People with Developmental Disabilities, as well as private monies donated to The Center for Discovery. The content is solely the responsibilities of the authors and does not necessarily represent the official views of the funding agencies.

The Department of Health Psychology is in the MU School of Health Professions, and the Department of Radiology is in the MU School of Medicine.

Harvard University to Launch Center for Autism Research

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Autism and related disorders—a constellation of neurodevelopmental conditions affecting one in 59 children in the United States alone—have become one of modern medicine’s most confounding mysteries. The condition is believed to arise from the complex interplay between genes and environment, yet its basic biology remains largely a black box.

Now, a new research effort at Harvard University led by Harvard Medical School is poised to identify the biologic roots and molecular changes that give rise to autism and related disorders with the goal of informing the development of better diagnostic tools and new therapies. Harvard University has received a $20 million gift from philanthropists Lisa Yang and Hock Tan, an alumnus of Harvard Business School, to establish The Hock E. Tan and K. Lisa Yang Center for Autism Research at Harvard Medical School. The latest gift brings the total autism-related research funding provided by Yang and Tan to nearly $70 million.

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The center will serve as a hub that brings together the diverse expertise of scientists and clinicians working throughout Harvard University, Harvard Medical School and its affiliated hospitals.

“There is an urgent need to understand the fundamental biology of autism,” said Michael Greenberg, chair of the Department of Neurobiology at Harvard Medical School and the center’s inaugural faculty leader. “I strongly believe that the multidisciplinary expertise convened by this center will propel us into a new era of autism research, enhancing our understanding of the condition and yielding critical new insights into its causes. This generous gift will be transformative for the field.”

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Working under the premise that autism’s complexity demands the cross-pollination of diverse expertise across different modes of scientific inquiry, the center will encompass the efforts of basic, translational and clinical scientists from the entire Harvard ecosystem. The center will have its administrative home within the Harvard Brain Science Initiative, which brings together researchers from Harvard Medical School and its affiliated hospitals as well as from the Harvard Faculty of Arts and Sciences, the Harvard T.H. Chan School of Public Health and the Harvard John A. Paulson School of Engineering and Applied Sciences. “Neuroscience has reached a unique inflection point. Advances such as single-cell analysis and optogenetics, coupled with an unprecedented ability to visualize molecular shifts down to the minutest level, will enable today’s researchers to tackle a disorder as dauntingly complex as autism,” said Harvard Medical School Dean George Q. Daley.

“Medical history has taught us that truly transformative therapies flow only from a clear understanding of the fundamental biology that underlies a condition,” Daley added. “This gift will allow our researchers to generate critical insights about autism and related disorders.”

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Investigators at the new Harvard University center will collaborate with peer researchers at MIT and complement efforts already underway at The Hock E. Tan and K. Lisa Yang Center for Autism Research at the McGovern Institute for Brain Research at MIT, with the unique strengths of each institution converging toward a shared goal: understanding the roots of autism, explaining the condition’s behavior and evolution and translating those insights into novel approaches to treat its symptoms.

“In a short time, the Tan-Yang Center at the McGovern Institute has supported groundbreaking research we believe will change our understanding of autism,” said Robert Desimone, the director of the sibling center at MIT. “We look forward to joining forces with the new center at Harvard, to greatly accelerate the pace of autism-related research.”

“We are excited and hopeful that these sibling centers at Harvard and MIT—two powerhouses of biomedical research—will continue to collaborate in a synergistic way and bring about critical new insights to our understanding of autism,” Yang said. Yang is a former investment banker who has devoted much of her time to mental health advocacy. Tan is president and CEO of Broadcom, a global infrastructure technology company. 

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Autism-spectrum disorders—neurodevelopmental conditions that typically emerge in the first few years of life—are marked by a cluster of symptoms, impaired social interactions and compromised communication skills. Yet exactly what portion of these cases is rooted in genetic mutations and how they are influenced by environmental factors is an area of lingering uncertainty. Another key area of uncertainty is how much of autism’s fundamental features arise in the brain and what influence organs and systems outside of the brain might have.

Two of the new center’s initial areas of inquiry will address these critical gaps in knowledge.

One group of researchers will focus on understanding precisely what goes awry during critical windows in the first two years of life—a period marked by rapid brain development, great neuroplasticity and intense wiring of the brain’s circuits. This is also the typical window of autism diagnosis. The scientists will try to understand what molecular, cellular or neural-circuitry changes underlie autism-fueling processes during this stage. Identifying such critical changes can help illuminate how experiences modulate brain development in individuals with autism.

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Another group of researchers will examine the role of factors arising from organs and organ systems outside the brain that may drive autism risk. For example, the peripheral nervous system—made up of nerve cells throughout the body that act as nodes to collect and transmit signals to the brain—has emerged as a central player in the development of autism.

Heightened sensitivity to even light touch is a common feature in autism and one of the disorder’s many perplexing symptoms. Recent research from neurobiologists and geneticists at Harvard Medical School has not only identified the molecular changes that give rise to heightened touch sensitivity in autism-spectrum disorders but also points to a possible treatment for the condition.

Autism rates increasing fastest among black and Hispanic children

Autism rates among racial minorities in the United States have increased by double digits in recent years, with black rates now exceeding those of whites in most states and Hispanic rates growing faster than any other group, according to new University of Colorado Boulder research.

The study, published this month in the Journal of Autism and Developmental Disorders, also found that prevalence of autism among white youth is ticking up again, after flattening in the mid-2000s.

While some of the increase is due to more awareness and greater detection of the disorder among minority populations, other environmental factors are likely at play, the authors conclude.

“We found that rates among blacks and Hispanics are not only catching up to those of whites — which have historically been higher — but surpassing them,” said lead author Cynthia Nevison, an atmospheric research scientist with the Institute of Arctic and Alpine Research. “These results suggest that additional factors beyond just catch-up may be involved.”

For the study, Nevison teamed up with co-author Walter Zahorodny, an autism researcher and associate professor of pediatrics at Rutgers New Jersey Medical School, to analyze the most recent data available from the Individuals with Disabilities Education Act (IDEA) and the Autism and Developmental Disabilities Monitoring (ADDM) Network.

IDEA tracks prevalence, including information on race, among 3-to-5-year-olds across all 50 states annually. ADDM tracks prevalence among 8-year-olds in 11 states every two years.

The new study found that between birth year 2007 and 2013, autism rates among Hispanics age 3-5 rose 73%, while rates among blacks that age rose 44% and rates among whites rose 25%.

In 30 states, prevalence among blacks was higher than among whites by 2012.

In states with “high prevalence,” 1 in 79 whites, 1 in 68 blacks and 1 in 83 Hispanics born in 2013 have been diagnosed with autism by age 3-5.

Other states like Colorado fell in a “low-prevalence” category, but the authors cautioned that differences between states likely reflect differences in how well cases are reported by age 3-5. They also said the real prevalence is substantially higher, as many children are not diagnosed until later in life.

“There is no doubt that autism prevalence has increased significantly over the past 10 to 20 years, and based on what we have seen from this larger, more recent dataset it will continue to increase among all race and ethnicity groups in the coming years,” said Zahorodny.

In 2018, the Centers for Disease Control reported that about 1 in 59 children of all races have been diagnosed with autism and that rates had risen 15 percent overall from the previous two year period, largely due to better outreach and diagnosis among historically underdiagnosed minority populations. The new study challenges that explanation.

“Our data contradict the assertion that these increases are mainly due to better awareness among minority children,” said Zahorodny. “If the minority rates are exceeding the white rates that implies some difference in risk factor, either greater exposure to something in the environment or another trigger.”

Established risk factors associated with autism include advanced parental age, challenges to the immune system during pregnancy, genetic mutations, premature birth and being a twin or multiple.

The authors said that, based on current research, they cannot pinpoint what other environmental exposures might be factoring into the increases in autism. But they would like to see more research done in the field.