Shell-Shocked Crabs Can Feel Pain

Jan. 16, 2013 — The food and aquaculture industries should reconsider how they treat live crustaceans such as crabs, prawns and lobsters. That’s according to a Queen’s University Belfast researcher who has found that crabs are likely to feel pain.


The latest study by Professor Bob Elwood and Barry Magee from Queen’s School of Biological Sciences looked at the reactions of common shore crabs to small electrical shocks, and their behaviour after experiencing those shocks. The research has been published in the Journal of Experimental Biology.

Professor Elwood’s previous research showed that prawns and hermit crabs respond in a way consistent with pain. This latest study provides further evidence of this. Professor Elwood said: “The experiment was carefully designed to distinguish between pain and a reflex phenomenon known as nociception. The function of pain is to aid future avoidance of the pain source, whereas nociception enables a reflex response that provides immediate protection but no awareness or changes to long-term behaviour.

“While nociception is generally accepted to exist in virtually all animals the same is not true of pain. In particular, whether or not crustaceans experience pain remains widely debated.”

This latest study showed that shore crabs are willing to trade something of value to them — in this case a dark shelter — to avoid future electric shock. Explaining how the experiment worked, Professor Elwood said: “Crabs value dark hideaways beneath rocks where they can shelter from predators. Exploiting this preference, our study tested whether the crabs experienced pain by seeing if they could learn to give up a valued dark hiding place in order to avoid a mild electric shock.

“Ninety crabs were each introduced individually to a tank with two dark shelters. On selecting their shelter of choice, some of the crabs were exposed to an electric shock. After some rest time, each crab was returned to the tank. Most stuck with what they knew best, returning to the shelter they had chosen first time around, where those that had been shocked on first choice again experienced a shock. When introduced to the tank for the third time, however, the vast majority of shocked crabs now went to the alternative safe shelter. Those not shocked continued to use their preferred shelter.

“Having experienced two rounds of shocks, the crabs learned to avoid the shelter where they received the shock. They were willing to give up their hideaway in order to avoid the source of their probable pain.”

Professor Elwood says that his research highlights the need to investigate how crustaceans used in food industries, such as crabs, prawns and lobsters, are treated. He said: “Billions of crustacean are caught or reared in aquaculture for the food industry. In contrast to mammals, crustaceans are given little or no protection as the presumption is that they cannot experience pain. Our research suggests otherwise. More consideration of the treatment of these animals is needed as a potentially very large problem is being ignored.

“On a philosophical point it is impossible to demonstrate absolutely that an animal experiences pain. However, various criteria have been suggested regarding what we would expect if pain were to be experienced. The research at Queen’s has tested those criteria and the data is consistent with the idea of pain. Thus, we conclude that there is a strong probability of pain and the need to consider the welfare of these animals.”

 

Story Source:

The above story is reprinted from materials provided byQueen’s University Belfast.

Note: Materials may be edited for content and length. For further information, please contact the source cited above.


Journal Reference:

  1. B. Magee, R. W. Elwood. Shock avoidance by discrimination learning in the shore crab (Carcinus maenas) is consistent with a key criterion for pain.Journal of Experimental Biology, 2013; 216 (3): 353 DOI:10.1242/jeb.072041
Queen’s University Belfast (2013, January 16). ‘Shell-shocked’ crabs can feel pain.ScienceDaily. Retrieved January 25, 2013, from http://www.sciencedaily.com/releases/2013/01/130116195336.htm
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Scanning the Brain: Scientists Examine the Impact of fMRI Over the Past 20 Years

Jan. 16, 2013 — Understanding the human brain is one of the greatest scientific quests of all time, but the available methods have been very limited until recently. The development of functional magnetic resonance imaging (fMRI) — a tool used to gauge real-time brain activity by measuring changes in blood flow — opened up an exciting new landscape for exploration.


Now, twenty years after the first fMRI study was published, a group of distinguished psychological scientists reflect on the contributions fMRI has made to our understanding of human thought. Their reflections are published as part of a special section of the January 2013 issue ofPerspectives on Psychological Science, a journal of the Association for Psychological Science.

In the last two decades, many researchers have used fMRI to try to answer various questions about the brain and mind. But some are not convinced of its usefulness.

“Despite the many new methods and results derived from fMRI research, some have argued that fMRI has done very little to advance knowledge about cognition and, in particular, has done little to advance theories about cognitive processes,” write Mara Mather, Nancy Kanwisher, and John Cacioppo, editors of the special section.

The aim of the special section is to tackle the question of how fMRI results have (or have not) changed the way we think about human psychology and the brain, resulting in a collection of 12 provocative articles.

Some of the authors argue that fMRI has fundamentally changed that way that researchers think about the aging mind. According to researchers Tor Wager and Lauren Atlas, fMRI may also provide a more direct way of measuring pain.

Others discuss the contributions fMRI has made to the longstanding debate about whether cognitive operations are modular or distributed across domains. And some emphasize the reciprocal relationship between fMRI and cognitive theories, highlighting how each informs the others.

As appealing as fMRI images might be, researchers Martha Farah and Cayce Hook find little support for the claim that fMRI data has a “seductive allure” that makes it more persuasive than other types of data.

In their concluding commentary, Mather, Cacioppo, and Kanwisher argue that fMRI does provide unique insights to our understanding of cognition. But, as powerful as it is, the researchers acknowledge that there are some questions fMRI will never answer.

“The best approach to answering questions about cognition,” say Mather, Cacioppo, and Kanwisher, “is a synergistic combination of behavioral and neuroimaging methods, richly complemented by the wide array of other methods in cognitive neuroscience.”


Story Source:

The above story is reprinted from materials provided byAssociation for Psychological Science.

Note: Materials may be edited for content and length. For further information, please contact the source cited above.


Journal Reference:

  1. M. Mather, J. T. Cacioppo, N. Kanwisher. Introduction to the Special Section: 20 Years of fMRI–What Has It Done for Understanding Cognition? Perspectives on Psychological Science, 2013; 8 (1): 41 DOI:10.1177/1745691612469036
Association for Psychological Science (2013, January 16). Scanning the brain: Scientists examine the impact of fMRI over the past 20 years. ScienceDaily. Retrieved January 25, 2013, from http://www.sciencedaily.com/releases/2013/01/130116163715.htm

New ‘Social’ Chromosome Discovered in the Red Fire Ant

Jan. 16, 2013 — Researchers have discovered a social chromosome in the highly invasive fire ant that helps to explain why some colonies allow for more than one queen ant, and could offer new solutions for dealing with this pest.


The red fire ants live in two different types of colonies: some colonies strictly have a single queen while other colonies contain hundreds of queens.

Publishing in the journal Nature on January 16, scientists have discovered that this difference in social organisation is determined by a chromosome that carries one of two variants of a ‘supergene’ containing more than 600 genes.

The two variants, B and b, differ in structure but have evolved similarly to the X and Y chromosomes that determine the sex of humans. If the worker fire ants in a colony carry exclusively the B variant, they will accept a single BB queen, but a colony that includes worker fire ants with the b variant will accept multiple Bb queens. The scientists analysed the genomes of more than 500 red fire ants to understand this phenomenon.

“This was a very surprising discovery — similar differences in chromosomal structure are linked to wing patterns in butterflies and to cancer in humans but this is the first supergene ever identified that determines social behaviour,” explains co-author Dr Yannick Wurm, from Queen Mary’s School of Biological and Chemical Sciences.

“We now understand that chromosomal variants determine social form in the fire ant and it’s possible that special chromosomes also determine fundamental traits such as behaviour in other species.”

During the reproductive season, young winged queens from both types of colonies emerge for their mating flights and are fertilised by males. Young queens destined to establish their own single-queen colonies disperse far and wide. This social form is highly successful at invading new territories. The other young queens join existing multiple-queen colonies close to their maternal colony. The multiple queens cooperating in such colonies are able to produce more workers than are found in a single-queen colony. This makes multiple queen colonies the more successful social form in busy environments.

The red fire ant is infamous for its painful sting in South America where it is a native species, and in many other parts of the world where its aggressiveness and high population density have made it an invasive pest. It was accidentally introduced to the Southern USA in the 1930s and has since spread to many warm parts of the world including China and Australia. Efforts at controlling the spread of this species have largely been unsuccessful, as indicated by its Latin name,Solenopsis invicta, meaning “the invincible.”

Dr. Wurm added, “Our discovery could help in developing novel pest control strategies. For example, a pesticide could artificially deactivate the genes in the social chromosome and induce social anarchy within the colony.”

 

Story Source:

The above story is reprinted from materials provided byQueen Mary, University of London.

Note: Materials may be edited for content and length. For further information, please contact the source cited above.


Journal Reference:

  1. John Wang, Yannick Wurm, Mingkwan Nipitwattanaphon, Oksana Riba-Grognuz, Yu-Ching Huang, DeWayne Shoemaker, Laurent Keller. A Y-like social chromosome causes alternative colony organization in fire ants.Nature, 2013; DOI: 10.1038/nature11832
Queen Mary, University of London (2013, January 16). New ‘social’ chromosome discovered in the red fire ant. ScienceDaily. Retrieved January 25, 2013, from http://www.sciencedaily.com/releases/2013/01/130116131403.htm

Language Mixing in Children Growing Up Bilingual

Jan. 16, 2013 — Language mixing — using elements from two languages in the same sentence — is frequent among bilingual parents and could pose a challenge for vocabulary acquisition by one- and two-year-old children, according to a new study by Concordia University psychology professor Krista Byers-Heinlein. Those results are likely temporary, however, and are often counterbalanced by cognitive advantages afforded to children raised in a bilingual environment.


With immigration and international mobility on the rise, early exposure to two languages has become the norm for many children across Canada, particularly those raised by parents who themselves are bilingual.

How do these bilingual parents use their two languages when interacting with their young children? Until recently, little has been known about how often parents switch between languages when interacting with their toddlers, and whether such exposure to language mixing influences vocabulary size.

To find the answers, Byers-Heinlein, who is also director of the Concordia Infant Research Laboratory and a member of the Centre for Research in Human Development, collaborated with Dr. Janet Werker’s Infant Studies Centre in Vancouver. She recruited 181 bilingual parents who spoke English as well as another language, and examined how often and in what situations they mixed languages while speaking with their children. Each parent had a one- or two-year-old child being raised bilingually or trilingually, having heard English and one or two other languages regularly since birth.

Rather than being a rare phenomenon, the results showed that language mixing is common in interactions between bilingual parents and their children. Indeed, 90 per cent of parents reported mixing their languages in interactions with their children. Parents did not mix their languages haphazardly, however, but instead reported principled reasons for mixing. For example, they borrowed words from the other language when there was no adequate translation, when they were not sure of a word, and when the word was hard to pronounce. Parents also reported frequently borrowing words from one language when teaching new words to their children in the other. Thus, bilingual parents might use language mixing as a strategy to make sure their children learn words equally in both languages.

Byers-Heinlein then examined the vocabulary size of 168 children of parents who had responded to the study. All of the children were learning English, but their non-English language varied widely — from German to Japanese, French to Farsi. As such, she focused on children’s English vocabulary size, while statistically controlling for the words that children likely knew in their non-English language.

She found that exposure to parental language mixing predicted significantly smaller comprehension vocabularies (words understood) in the younger children, and marginally smaller production vocabularies (words spoken) in the older children.

Why is that? Byers-Heinlein explains that, “high rates of language mixing make it harder for children to categorize words they hear. That could lead to slower word learning and smaller vocabularies. It also seems that it’s more difficult to learn a word from a mixed-language sentence than from a single-language sentence.”

But that in no way means that children raised in a bilingual environment are at a disadvantage. Byers-Heinlein cautions that, “even if exposure to language mixing is initially challenging for vocabulary acquisition, it likely has benefits over the long term.”

“Studies comparing monolingual and bilingual infants have shown that bilinguals are more adept at switching between strategies and are more able to learn two rules at the same time,” she explains. “Infants exposed to frequent language mixing could develop specific strategies for coping with this type of input. That could lead to cognitive advantages that would outweigh any initial difficulties brought about by language mixing.”

Byers-Heinlein is now undertaking new research with French-English bilinguals in Montreal to examine whether these findings hold in other bilingual communities, and when children’s vocabularies are assessed in both of their languages.


Story Source:

The above story is reprinted from materials provided byConcordia University.

Note: Materials may be edited for content and length. For further information, please contact the source cited above.


Concordia University (2013, January 16). Language mixing in children growing up bilingual. ScienceDaily. Retrieved January 25, 2013, from http://www.sciencedaily.com/releases/2013/01/130116123641.htm

Leopards and Tigers in India: New Genetics Research Underscores Importance of Protecting Forest Corridors

Jan. 16, 2013 — As rapid economic expansion continues to shape the Asian landscape on which many species depend, time is running out for conservationists aiming to save wildlife such as tigers and leopards. Scientists at the Smithsonian Conservation Biology Institute have used genetic analysis to find that the natural forest corridors in India are essential to ensuring a future for these species. According to two studies recently published in two papers, these corridors are successfully connecting populations of tigers and leopards to ensure genetic diversity and gene flow.


The results of the study that focused on tigers were published in Ecology and Evolution, and the results from the study that tracked leopards were published in Diversity and Distributions.

“This research provides crucial information about the need to maintain these vital veins to support tiger and leopard populations,” said Sandeep Sharma, SCBI visiting scholar and lead author of the Ecology and Evolution paper. “These habitats and corridors in India are threatened by infrastructural developments and need to be conserved if we want to save these species for future generations.”

Habitat fragmentation can divide populations of species into isolated groups, which can lead to inbreeding and a genetic bottleneck that affects the long-term viability of the population. Scientists can determine the scope of such isolation by analyzing the extent to which groups of the same species from one range have become genetically distinct. The authors of the two papers used fecal samples to analyze the genetics of tiger and leopard populations in four reserves in central India: Satpura, Melghat, Pench and Kanha. The Kanha and Pench reserves and the Satpura and Melghat reserves are connected via forest corridors that tigers, leopards, humans and cattle share.

The researchers found that both tiger and leopard populations in the reserves had maintained a high level of genetic diversity. Neither tigers nor leopards were genetically distinct, with one exception among the leopards, which the scientists hope to explain with additional research. The corridors appear to allow individuals to move between reserves, facilitating genetic exchange.

However, the proliferation of roads, rail lines, mining, urbanization and other forms of development through the corridors jeopardize these species’ ability to move between reserves. Several coal mines have been proposed in the forest corridor between the Satpura and Pench tiger reserves, as has the widening of a national highway (NH-7) and a broad-gauge railway line that cut across the corridor between the Kanha and Pench tiger reserves.

“By looking at two species, we were really able to illustrate the functionality of these corridors,” said Trishna Dutta, SCBI visiting student and lead author of the Diversity and Distributions paper. “Conserving a whole landscape, rather than piecemeal protected areas, would ensure a better chance for the long-term persistence of these and other species.”

The Indian subcontinent contains the largest number of tiger conservation areas, which are home to 60 percent of the world’s wild tigers. Leopard range has historically extended through most of sub-Saharan Africa, along parts of the North African coast, through central, south and southeast Asia and north to the Amur River valley in Russia.

In addition to Sharma and Dutta, the papers’ other SCBI authors are Jesús Maldonado, a research geneticist at SCBI’s Center for Conservation and Evolutionary Genetics, and John Seidensticker, head of SCBI’s Conservation Ecology Center. The other authors are Thomas Wood in the Department of Environmental Science and Policy at George Mason University and H.S. Panwar, former director of Project Tiger India and Wildlife Institute of India.

The Smithsonian Conservation Biology Institute plays a key role in the Smithsonian’s global efforts to understand and conserve species and train future generations of conservationists. Headquartered in Front Royal, Va., SCBI facilitates and promotes research programs based at Front Royal, the National Zoo in Washington, D.C., and at field research stations and training sites worldwide.

 

Story Source:

The above story is reprinted from materials provided bySmithsonian Institution.

Note: Materials may be edited for content and length. For further information, please contact the source cited above.


Journal References:

  1. Sandeep Sharma, Trishna Dutta, Jesús E. Maldonado, Thomas C. Wood, Hemendra Singh Panwar, John Seidensticker. Spatial genetic analysis reveals high connectivity of tiger (Panthera tigris) populations in the Satpura-Maikal landscape of Central IndiaEcology and Evolution, 2012; 3 (1): 48 DOI: 10.1002/ece3.432
  2. Trishna Dutta, Sandeep Sharma, Jesús E. Maldonado, Thomas C. Wood, H. S. Panwar, John Seidensticker. Fine-scale population genetic structure in a wide-ranging carnivore, the leopard (Panthera pardus fusca)in central IndiaDiversity and Distributions, 2012; DOI:10.1111/ddi.12024
Smithsonian Institution (2013, January 16). Leopards and tigers in India: New genetics research underscores importance of protecting forest corridors. ScienceDaily. Retrieved January 25, 2013, from http://www.sciencedaily.com/releases/2013/01/130116123013.htm

Research Reveals Exactly How the Human Brain Adapts to Injury

Jan. 16, 2013 — For the first time, scientists at Carnegie Mellon University’s Center for Cognitive Brain Imaging (CCBI) have used a new combination of neural imaging methods to discover exactly how the human brain adapts to injury. The research, published in Cerebral Cortex, shows that when one brain area loses functionality, a “back-up” team of secondary brain areas immediately activates, replacing not only the unavailable area but also its confederates.

This image shows four sources of evidence of takeover by a right-hemisphere area following the disablement of its left hemisphere counterpart. (Credit: Carnegie Mellon University)

“The human brain has a remarkable ability to adapt to various types of trauma, such as traumatic brain injury and stroke, making it possible for people to continue functioning after key brain areas have been damaged,” said Marcel Just, the D. O. Hebb Professor of Psychology at CMU and CCBI director. “It is now clear how the brain can naturally rebound from injuries and gives us indications of how individuals can train their brains to be prepared for easier recovery. The secret is to develop alternative thinking styles, the way a switch-hitter develops alternative batting styles. Then, if a muscle in one arm is injured, they can use the batting style that relies more on the uninjured arm.”

For the study, Just, Robert Mason, senior research psychologist at CMU, and Chantel Prat, assistant professor of psychology at the University of Washington, used functional magnetic resonance imaging (fMRI) to study precisely how the brains of 16 healthy adults adapted to the temporary incapacitation of the Wernicke area, the brain’s key region involved in language comprehension. They applied Transcranial Magnetic Stimulation (TMS) in the middle of the fMRI scan to temporarily disable the Wernicke area in the participants’ brains. The participants, while in the MRI scanner, were performing a sentence comprehension task before, during and after the TMS was applied. Normally, the Wernickearea is a major player in sentence comprehension.

The research team used the fMRI scans to measure how the brain activity changed immediately following stimulation to the Wernicke area. The results showed that as the brain function in the Wernicke area decreased following the application of TMS, a “back-up” team of secondary brain areas immediately became activated and coordinated, allowing the individual’s thought process to continue with no decrease in comprehension performance.

The brain’s back-up team consisted of three types of brain regions:

(1) contralateral areas — areas that are in the mirror-image location of the brain;

(2) areas that are right next to the impaired area; and

(3) a frontal executive area.

“The first two types of back-up areas have similar brain capabilities as the impaired Wernicke area, although they are less efficient at the capability,” Just said. “The third area plays a strategic role as in responding to the initial impairment and recruiting back-up areas with similar capabilities.”

Additionally, the research showed that impairing the Wernicke area also negatively affected the cortical partners with which the Wernicke area had been working. “Thinking is a network function,” Just explained. “When a key node of a network is impaired, the network that is closely collaborating with the impaired node is also impaired. People do their thinking with groups of brain areas, not with single brain areas.”

Mason, the study’s lead author, noted that following the TMS, the impaired area and its partners gradually returned to their previous levels of coordinated activity, while the back-up team of brain areas was still in place. “This means, that for some period of time, there were two cortical teams operating simultaneously, explaining why performance is sometimes improved by TMS,” he said.

This research builds on Just’s previous research on brain resilience after stroke and brain training to remediate dyslexia. The studies are motivated by a computational theory, called 4CAPS, that provides an account of how autonomous brain systems dynamically self-organize themselves in response to changing circumstances, which the researchers believe to be the basis of fluid intelligence.

Just, who uses brain imaging to understand how brain processes underpin various types of human thought, has helped to establish Carnegie Mellon as a world leader in brain sciences. The university recently launched a Brain, Mind and Learning initiative to build from its research excellence in psychology, computer science and computation to continue to solve real-world problems.


Story Source:

The above story is reprinted from materials provided byCarnegie Mellon University.

Note: Materials may be edited for content and length. For further information, please contact the source cited above.


Journal Reference:

  1. R. A. Mason, C. S. Prat, M. A. Just. Neurocognitive Brain Response to Transient Impairment of Wernicke’s Area.Cerebral Cortex, 2013; DOI: 10.1093/cercor/bhs423
Carnegie Mellon University (2013, January 16). Research reveals exactly how the human brain adapts to injury. ScienceDaily. Retrieved January 25, 2013, from http://www.sciencedaily.com/releases/2013/01/130116092151.htm