Archive for the ‘CIAF’ Category

It seems simple: Walk to the refrigerator and grab a drink.

But Brett Larsen, 37, opens the door gingerly — peeks in — closes it, opens it, closes it and opens it again. This goes on for several minutes.

When he finally gets out a bottle of soda, he places his thumb and index finger on the cap, just so. Twists it open. Twists it closed. Twists it open.

“Just think about any movement that you have during the course of a day — closing a door or flushing the toilet — over and over and over,” said Michele Larsen, Brett’s mother.

“I cannot tell you the number of things we’ve had to replace for being broken because they’ve been used so many times.”

At 12, Larsen was diagnosed with obsessive-compulsive disorder, or OCD. It causes anxiety, which grips him so tightly that his only relief is repetition. It manifests in the smallest of tasks: taking a shower, putting on his shoes, walking through a doorway.

There are days when Larsen cannot leave the house.

“I can only imagine how difficult that is to live with that every single living waking moment of your life,” said Dr. Gerald Maguire, Larsen’s psychiatrist.

In a last-ditch effort to relieve his symptoms, Larsen decided to undergo deep brain stimulation. Electrodes were implanted in his brain, nestled near the striatum, an area thought to be responsible for deep, primitive emotions such as anxiety and fear.

Brett’s OCD trigger

Brett says his obsessions and compulsions began when he was 10, after his father died.

“I started worrying a lot about my family and loved ones dying or something bad happening to them,” he said. “I just got the thought in my head that if I switch the light off a certain amount of times, maybe I could control it somehow.

“Then I just kept doing it, and it got worse and worse.”

“Being OCD” has become a cultural catchphrase, but for people with the actual disorder, life can feel like a broken record. With OCD, the normal impulse to go back and check if you turned off the stove, or whether you left the lights on, becomes part of a crippling ritual.

The disease hijacked Larsen’s life (he cannot hold down a job and rarely sees friends); his personality (he can be stone-faced, with only glimpses of a slight smile); and his speech (a stuttering-like condition causes his speaking to be halting and labored.)

He spent the past two decades trying everything: multiple medication combinations, cognitive behavioral therapy, cross-country visits to specialists, even hospitalization.

Nothing could quell the anxiety churning inside him.

“This is not something that you consider first line for patients because this is invasive,” said Maguire, chair of psychiatry and neuroscience at the University of California Riverside medical school, and part of the team evaluating whether Larsen was a good candidate for deep brain stimulation. “It’s reserved for those patients when the standard therapies, the talk therapies, the medication therapies have failed.”

Deep brain stimulation is an experimental intervention, most commonly used among patients with nervous system disorders such as essential tremor, dystonia or Parkinson’s disease. In rare cases, it has been used for patients with intractable depression and OCD.

The electrodes alter the electrical field around regions of the brain thought to influence disease — in some cases amplifying it, in others dampening it — in hopes of relieving symptoms, said Dr. Frank Hsu, professor and chair of the department of neurosurgery at University of California, Irvine.

Hsu says stimulating the brain has worked with several OCD patients, but that the precise mechanism is not well understood.

The procedure is not innocuous: It involves a small risk of bleeding in the brain, stroke and infection. A battery pack embedded under the skin keeps the electrical current coursing to the brain, but each time the batteries run out, another surgical procedure is required.

‘I feel like laughing’

As doctors navigated Larsen’s brain tissue in the operating room — stimulating different areas to determine where to focus the electrical current — Larsen began to feel his fear fade.

At one point he began beaming, then giggling. It was an uncharacteristic light moment for someone usually gripped by anxiety.

In response to Larsen’s laughter, a staff member in the operating room asked him what he was feeling. Larsen said, “I don’t know why, but I feel happy. I feel like laughing.”

Doctors continued probing his brain for hours, figuring out what areas — and what level of stimulation — might work weeks later, when Larsen would have his device turned on for good.

In the weeks after surgery, the residual swelling in his brain kept those good feelings going. For the first time in years, Larsen and his mother had hope for normalcy.

“I know that Brett has a lot of normal in him, even though this disease eats him up at times,” said Michele Larsen. “There are moments when he’s free enough of anxiety that he can express that. But it’s only moments. It’s not days. It’s not hours. It’s not enough.”

Turning it on

In January, Larsen had his device activated. Almost immediately, he felt a swell of happiness reminiscent of what he had felt in the OR weeks earlier.

But that feeling would be fleeting — the process for getting him to an optimal level would take months. Every few weeks doctors increased the electrical current.

“Each time I go back it feels better,” Larsen said. “I’m more calm every time they turn it up.”

With time, some of his compulsive behaviors became less pronounced. In May, several weeks after his device was activated, he could put on his shoes with ease. He no longer spun them around in an incessant circle to allay his anxiety.

But other behaviors — such as turning on and shutting off the faucet — continued. Today, things are better, but not completely normal.

Normal, by society’s definition, is not the outcome Larsen should expect, experts say. Patients with an intractable disease who undergo deep brain stimulation should expect to have manageable OCD.

Lately, Larsen feels less trapped by his mind. He is able to make the once interminable trek outside his home within minutes, not hours. He has been to Disneyland with friends twice. He takes long rides along the beach to relax.

In his mind, the future looks bright.

“I feel like I’m getting better every day,” said Larsen, adding that things like going back to school or working now feel within his grasp. “I feel like I’m more able to achieve the things I want to do since I had the surgery.”

Thanks to Da Brayn for bringing this to the attention of the It’s Interesting community.

http://www.cnn.com/2014/06/24/health/brain-stimulation-ocd/?c=&page=0

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By Mary Bates

I’ve written before about the evolutionary arms race between brood parasites (who lay their eggs in the nests of other birds, leaving them to raise their chicks) and their hosts. In these systems, host birds benefit from recognizing and removing parasite eggs or chicks from their nests. Meanwhile, the brood parasites keep trying to trick the hosts into accepting and caring for their young.

Hosts must walk a precarious line in defending themselves against brood parasites. Too lax, and they end up spending valuable time and energy raising another bird’s chicks. Too strict, and they run the risk of rejecting one of their own eggs by mistake. For the best results, hosts should modify how defensive they are against parasites in relation to the risk they pose.

A few years ago, Diane Colombelli-Négrel, Sonia Kleindorfer, and colleagues from Flinders University in Australia discovered a remarkable way one bird fights back against brood parasites. Female superb fairy-wrens teach their embryos a “password” while they’re still in their eggs. Each female’s incubation call contains a unique acoustic element. After they hatch, fairy-wren chicks incorporate this unique element into their begging calls to ask for food. Colombelli-Négrel, Kleindorfer, and colleagues showed that chicks whose begging calls most resembled their mothers’ incubation calls received more food. But the brood parasites of the fairy-wren, Horsfield’s bronze-cuckoos, produced begging calls that did not so closely resemble the parental password.

In a new study, Colombelli-Négrel, Kleindorfer, and colleagues again looked at the relationship between superb fairy-wrens and Horsfield’s bronze-cuckoos to see if a greater threat of brood parasitism would cause the fairy-wren to up its teaching efforts.

First, the researchers recorded calls from 17 fairy-wren nests in South Australia. They found the similarity between the mother’s password and the chick’s begging call was predicted by the number of incubation calls produced by the mother: If females made many incubation calls, their chicks ended up producing more similar begging calls.Next, the researchers conducted a playback experiment at 29 nests. They broadcast either the song of Horsfield’s bronze-cuckoo or a neutral bird. After the cuckoo calls, but not after the neutral bird calls, female fairy-wrens made more incubation calls to their embryos. In other words, female fairy-wrens that heard a cuckoo near their nest increased their efforts to teach their password to their embryos.

Colombelli-Négrel and Kleindorfer say their results provide a mechanism for how fairy-wrens could get better at decision-making and lower the probability of committing an acceptance error for a cuckoo chick or a rejection error for one of their own chicks.“When there are cuckoos in the area, you should call more to your eggs so that they have a higher call similarity after hatching and you can decide if the offspring is yours,” Colombelli-Négrel and Kleindorfer wrote in an email. “We show a mechanism that starts in the nest and involves active teaching and sensorimotor learning in embryos.”Colombelli-Négrel, Kleindorfer, and their colleagues are continuing to study how fairy-wrens teach their passwords to their chicks. They’re currently looking at how the fairy-wren embryos learn using heart rate and magnetic resonance imaging (MRI) scans, and whether parents do anything special to help their offspring learn, such as investing in egg nutrients that promote learning.

To beat a tricky brood parasite, superb fairy-wrens have to start teaching their offspring early and often. And when they detect a threat, these dedicated parents double-down on their teaching efforts to make sure their chicks get the message.

References:

Kleindorfer, S., Evans, C. and Colombelli-Négrel, D. (2014). Females that experience threat are better teachers. Biology Letters 10: 20140046. doi: 10.1098/rsbl.2014.0046.

Colombelli-Négrel, D., Hauber, M. E., Robertson, J., Sulloway, F. J., Hoi, H., Griggio, M. and Kleindorfer, S. (2012). Embryonic learning of vocal passwords in superb fairy-wrens reveals intruder cuckoo nestlings. Current Biology 22: 2155-2160. doi: 10.1016/j.cub.2012.09.025.

http://www.wired.com/2014/06/to-beat-a-parasite-birds-teach-their-young-a-secret-password/

By Tanya Lewis

Just as humans lament not pursuing a lover or bemoan having eaten that extra slice of chocolate cake, rats may experience feelings of regret, too, new research suggests.

When rats were given the option of visiting rooms that contained different foods, and they skipped a good deal for a worse one, they glanced back at the former room, rushed through eating the snack and were more likely to tolerate longer wait times for what they considered the more desirable food , researchers found.

Furthermore, the rats’ brain activity represented the missed opportunity, suggesting the animals were, in fact, experiencing regret over their choice.

“The rat is representing the counterfactual — the ‘what might have been,'” David Redish, a neuroscientist at the University of Minnesota in Minneapolis, and senior author of the study detailed today (June 8) in the journal Nature Neuroscience.

No other studies have shown convincingly that any animal besides humans experience regret, though some studies hinted it was possible, the researchers said.

How do you define regret? You can’t exactly ask a rat if it feels regret, but even if you could, it wouldn’t be proof, just as it can be difficult to tell if a human feels regret just by asking them.

It’s important to distinguish between regret and disappointment, Redish told Live Science. Regret occurs when you make a mistake, but recognize there’s an alternate action you could have taken that would have resulted in a better outcome, he said. Disappointment happens when “the world’s just not as good as you hoped, but it’s not necessarily your fault,” he said.

To test whether rats could feel regret, Redish and his graduate student Adam Steiner designed a kind of “restaurant row” for the animals — a circular enclosure with pathways leading off it to “restaurants” with different kinds of food, which were dispensed after some delay.

As a rat passed each pathway, it heard a tone that told the animal how long it would have to wait for the food (like being told the wait time at a restaurant). Each rat had its own favorite food, such as banana or chocolate, and would wait longer to get it, Redish said. Each rat was given an hour to explore the enclosure, during which it could only move in one direction between restaurants.

If the rat passed up a good deal — for instance, bypassing a food it liked in favor of a shorter wait time — and encountered a worse deal at the next restaurant, it would glance backward at the one it passed up. Not only that, the rat rushed through eating its chosen food, much like a regretful human would, and was more likely to take a “worse deal” in the future, the researchers said.

But the rats’ behavior was only part of the story. The researchers also made electrical recordings of the rats’ brains during the task, from neurons in the orbitofrontal cortex, the part of the brain that is active in human brain scans when people feel regret. Decoding these signals allowed the researchers to “read the rat’s mind,” Redish said.

Surprisingly, when the rats were looking back at the restaurant they ultimately passed up, their brains showed a representation of entering that restaurant — not of the food they missed. The findings suggest the animals were expressing regret over their actions, rather than just disappointment, the researchers said.

If rats can feel regret, what about other animals? Redish speculates that any mammal might be capable of the feeling, because they have many of the same brain structures as rats and humans.

“Regret is something we think of as very human and very cognitive,” Redish said, but “we’re seeing that the rats are much more cognitive than we thought.”

http://www.livescience.com/46184-rats-experience-regret.html