Where is Language Located in the Brain? There are Two Sides to this Story - [Journal Article]

(BPS Research Digest, 21, November 2013) - Simple facts about the brain are rare, but one of them is that for most people language function is located mainly in their left brain hemisphere. The stats vary according to the measures used, but this is the situation for around 95 per cent of right-handers and approximately 75 per cent of left-handers. When it comes to the brain though, few things are straight-forward.

Journal article: Bilateral representation of language: A critical review and analysis of some unusual cases.

If we dig deeper, as Byron Bernal and Alfredo Ardila have done for a new review paper, we find a more complex, two-sided story. The extent to which language is dominated by the left hemisphere is not fixed. It increases through childhood and adolescence, and then this trend reverses in old age, with signs of greater sharing of language function across the brain hemispheres in later life. 

Moreover, by characterising people in binary fashion as having their language abilities housed either in their left or right hemisphere, we ignore those people for whom language is a genuinely "bilateral function," meaning that both brain hemispheres are substantially involved.

As Bernal and Ardila point out, a dramatic demonstration of this comes from the Wada test, named after  Japanese neurologist Juhn Atsushi Wada. With the patient awake, anaesthetic is injected into the neck or head on one side to effectively shut down function in that side of the brain. Speech and language comprehension tests are conducted first with one hemisphere silenced, then the other.

Looking at the results from 1,799 Wada tests, most of which were conducted with epilepsy patients prior to surgery, Bernal and Ardila found that 10 per cent of right-handers and 27 per cent of left-handers (and the ambidextrous) showed evidence that their language function was supported by both brain hemispheres.

The way that bilateral language function manifests in the Wada test varies from patient to patient. In some, shutting down one hemisphere has no effect on their language abilities, while shutting down the other only partially interferes with language. In other patients, shutting down one hemisphere completely impairs language, while shutting down the other also has a partial adverse effect. And in a final group, shutting down either hemisphere results in only a partial impairment to language.

The reason for these different patterns, Bernal and Ardila explain, is that there are various ways that language function can be shared between the hemispheres. Using brain scans from real life case studies, they show how in some people all functions of language are shared between the left and right brain, whereas for other people some sub-functions of language are bilateral, but not others. 

For instance, the faculties involved in language comprehension might be bilateral, but the faculties of language production are not, or vice versa (similar dissociations can be found for processing sound and meaning). Related to this, some people show evidence that the different steps of language function are distributed sequentially between the hemispheres (e.g. one stage processed on one side, the next stage on the other), so there is no redundancy, whereas other people show a kind of parallel arrangement where both hemispheres are able to perform the same steps of language processing.

We need to be cautious when extrapolating from patient studies to healthy people because it's possible that the brain has altered its function to adapt to disease. This caveat aside, Bernal and Ardila's fascinating review is a reminder of the brain's complexity. The factoid that in most people language is left-lateralized conceals a messy reality. "It is a frequent understanding that language lateralization is a matter of all or nothing," write Bernal and Ardila. "However, language dominance is mostly a matter of hemispheric advantage for a specific multi-modular cognitive function: language. As such, language in a strict sense is up to a certain point a bilateral brain function."

Unusual Animal Intelligence - [Magazine article]

(Iflscience.com, 22, October 2013) - Before 1960 most of the work surrounding animal intelligence was centred around behaviour, with famous experiments such as Pavlov’s dogs and Thorndike’s operant conditioning. After 1960, the field began to shift to understand animal cognition and there has been much debate whether animals have an actual consciousness. 

The full extent of what animals think may never be known, but we already have seen amazing intelligence from some unlikely sources.

Crows

Crows are insanely intelligent creatures. They are able to recognize human faces and hold a grudge against the ones they don’t like. In order to study the crows they had to be collected and properly tagged. The scientists who handled the birds quickly fell out of favor with the crows. The next time the researchers entered the enclosure they were greeted by the crows dive bombing and attacking them. If the same researchers came back wearing a mask that the crows hadn’t seen before, they were left alone. It also appears that the crows conspire with one another and share information about which humans they don’t like. Crows who were absent when a particular researcher had handled the other birds would still respond with hostility upon seeing the scientist at a later date.

Their amazing intelligence is not always used to start fights -  they are skilled at using tools in order to retrieve food or solve problems. Crows readily use sticks, rocks, and wires to retrieve food from hidden places. If the proper tool is not at their disposal, they can actually make one to suit the job. What's more, these crows can use tools better than many primates.

Aesop’s “The Crow and the Pitcher” fable describes crows’ ingenuity. A crow wanted a drink of water, but was unable to reach down into the pitcher. Rather than give up, it dropped pebble after pebble into the pitcher until the water rose high enough for it to have a drink. It is a 2600-year-old story of tenacity. Modern scientists have decided to test the fable and found that it was scientifically accurate. 

Dolphins

“So long, and thanks for all the fish.”

Dolphins have long been celebrated as some of the most clever animals in the world. Their brains are extremely large for their body size, have a neocortex (where higher function takes place) much more intricate than humans and the region of the brain that is in charge of self awareness is enlarged when compared to other animals. 

Dolphins live in social societies and communication is integral to its success. They do not have vocal cords as humans do, but use a combination of clicks, squeaks, creaks, and buzzes to talk to their fellow cetaceans, though scientists have not been able to discern an actual language yet. Body language is also an important communication tool Dolphin whistles are unique to individuals and are developed in the first month of life.

It was recently discovered that dolphins remember the signature call of their friends, even if they hadn’t seen each other in over 20 years. This might help explain how dolphins can leave and join different pods so easily over the course of their lifetime.

Dolphins are so intelligent that India has recently put a ban on their captivity. India’s Ministry of the Environment and Forests has labeled cetaceans as "non-human persons" and released a statement saying they are not to be captured for entertainment purposes by any person or institution, whether they are public or private.

Pigs

While it might be surprising to some pigs are quite intelligent and many would compare that intellect to be on the same level as dolphins and higher apes. 

Part of this intellect might be because large chunks of pig genome are virtually identical to humans, though our last common ancestor died out 100 million years ago. Pigs love to become couch potatoes and would rather eat, drink, smoke, and watch TV than be active; not unlike many people.

When introduced to a mirror, they were initially fascinated by the pig in the reflection and tried to interact by nudging and vocalizing. While they could see food in the mirror, they tried looking behind the mirror only to end up hungry. The next time the mirror was presented, they were not interested in their own image, but instead used the reflection to find the bowl of food behind them in under 30 seconds. 

Pigs can also be trained to learn tricks fairly easily. However, if at first they don’t succeed, getting the courage to try again is a long process, especially if the pig got hurt in the attempt. Researchers speculate that the memory of the failure is a big hurdle to overcome for many pigs. Failures in training and living conditions can affect a pig's mood, as the animals are capable of having and expressing complex emotions.

Elephants

Elephants are the largest mammals on land, and it turns out that they have the brains to back up the brawn. 

It was recently discovered that with absolutely no training elephants understand when humans point. While standing in between two identical buckets, but one was filled with food, the elephants immediately chose the one that the human had gestured. While it is remarkable that elephants are able to spontaneously understand this body language, it becomes even more impressive since many great apes are not capable of the same level of understanding.

Captive elephants had no greater advantage than wild elephants with little human interaction, leading the scientists to believe that this is an innate response, and pointing on some level may exist in elephant populations.

In a different study highlighting the intelligence of these pachyderms a group of elephants competed against a group of humans in a teamwork exercise. Not only did the elephants beat the humans in the exercise, but they were able to do it using techniques that the researchers had not previously considered.

 

Altruism or manipulated helping? Altruism may have origins in manipulation - [Article]

(Phys.org, 19, Aug 2013) - Manipulation is often thought of as morally repugnant, but it might be responsible for the evolutionary origins of some helpful or altruistic behaviour, according to a new study.

Journal article: Evolution of manipulated behavior (apologies, article not live at time of publishing)

In evolutionary biology, manipulation occurs when an individual, the manipulator, alters the behaviour of another individual in ways that is beneficial to the manipulator but may be detrimental to the manipulated individual. Manipulation not only occurs in humans and animals but also at the cellular level, such as among cells in a multicellular organism, or in parasites, which can alter the behaviour of their hosts. 

Consider the case of the parasitic roundworm (Myrmeconema neotropicum), which once ingested by the tropical ant (Cephalotes atratus) in Central and South America, causes the ant to grow a bright red abdomen, mimicking berries. This bright abdomen constitutes a phenotype manipulated by the roundworm. Birds eat the "berries," or infected ants, and then spread the parasite in their droppings, which are subsequently collected by foraging Cephalotes atratus and fed to their larva, and the cycle of manipulated behaviour begins anew.

In the study published this week in the journal American Naturalist, the researchers developed a mathematical model for the evolution of manipulated behaviour and applied it to maternal manipulation in eusocial organisms, such as ants, wasps, and bees, which form colonies with reproductive queens and sterile workers. In the model, mothers produce two broods, and they manipulate the first-brood offspring to stay in the maternal site and help raise the second brood. 

Mothers can do this by disrupting the offspring's development in some way, for example through poor feeding or aggressive behaviour. Manipulated offspring of the first-brood stay and help to raise the second brood. Alternatively, first-brood offspring can resist manipulation and leave.

The researchers show that an offspring's resistance to manipulation may often fail to evolve, if the costs of resistance are high. In a sense, then, helping or altruistic behaviour is coerced through manipulation.

"The evidence in so-called primitive eusociality, where helping is often coerced through aggression or differential feeding, appears consistent with these results," said lead author Mauricio Gonzalez-Forero, who conducted the study while a graduate research assistant at the National Institute for Mathematical and Biological Synthesis.

What is dyslexia? But more importantly, why is it special?

(TEDEDUCATION, 13, August 2013) - Dyslexia affects up to 1 in 5 people, but the experience of dyslexia isn't always the same. This difficulty in processing language exists along a spectrum -- one that doesn't necessarily fit with labels like "normal" and "defective." Kelli Sandman-Hurley urges us to think again about dyslexic brain function and to celebrate the neurodiversity of the human brain.

Lesson by Kelli Sandman-Hurley, animation by Marc Christoforidis

Contagious Yawning in Dogs and Humans: Are dogs more empathetic towards their owners?

(National Geographic, 8, August 2013) - Pets yawn more in response to owners' yawns than strangers', study says.

Journal article: Familiarity Bias and Physiological Responses in Contagious Yawning by Dogs Support Link to Empathy

Dog owners who claim their pets know their feelings may be on to something: A new study shows that canines yawn more in response to their owners' yawns than they do to strangers' yawns.

That suggests dogs are "emotionally connected" to people, study leader Teresa Romero of the University of Tokyo said in a statement.

Scientists already knew that dogs sometimes yawn when they see people yawn, but it was unclear if that was considered a form of empathy or mild stress, as yawning can be caused by anxiety.

So Romero and her team set up an experiment in which 25 pet dogs watched both their owners and strangers yawn or pretend to yawn. (Read about why people yawn.)

The team ruled out stress when researchers saw no significant differences in the dogs' heartbeats during the experiments, according to the study, published August 7 in the journal PloS ONE.

Not only did the dogs in the study yawn more in response to their owners' yawns, they also yawned less when they saw fake yawns from their owners or from strangers, suggesting they were exhibiting true contagious yawning.

Contagious yawning occurs in humans, chimpanzees, baboons, and dogs.

In a similar study published last year, scientists found that people yawn more in response to the yawns of people they care about most.

In the case of people, scientists suspect that contagious yawning is a form of empathizing with people experiencing a feeling, which—in the case of yawning—usually means stress, anxiety, boredom, or fatigue.

Elisabetta Palagi, of the Institute of Cognitive Sciences and Technologies in Rome, noted that the study is the first time that scientists have shown contagious yawning occurring between different species.

"This could be the result of a long process of domestication," said Palagi, who wasn't involved in the study.  "Once more," she said, the study "demonstrates that dogs are capable of empathic abilities toward humans."

The Psychology of Music - [Pic] [Geeksaresexy.net]

Dolphins recognise their old friends even after 20 years of being apart

(The Independent – 7, August 2013) - New study shows that the mammals have the longest social memory of any non-human species

Dolphins are able to remember one another's signature calls for at least 20 years making it the longest memory for "faces" among animals - perhaps even surpassing the ability of people to remember one another from their appearances alone.

Every dolphin has a unique whistle which is used as a signature call and stays with them unchanged throughout life. These identifying noises are even more reliable than the facial features used by people to recognise each other, which notoriously change over time.

Now a study has shown that when dolphins have been separated for 20 years or more they are still able to distinguish the whistle call of a former close companion from a host of other calls emitted by complete strangers, scientists said.

This kind of "social memory" surpasses the recognition abilities of elephants, primates and all other intelligent animals that have been studied in this way, said Jason Bruck, who carried out the work whilst studying for is PhD at the University of Chicago.

"This research shows that dolphins have the potential for lifelong memory for each other regardless of relatedness, sex or duration of association. This is the first study to show that social recognition can last for at least 20 years in a nonhuman species," Dr Bruck said.

"This shows us an animal operating cognitively at a level that's very consistent with human social memory. This is the kind of study you can only do with captive groups where you know how long the animals have been apart. To do a similar study in the wild could be almost impossible," he said.

The study, published in the journal Proceedings of the Royal Society of London B, involved collecting the recorded signature whistles of 53 different bottlenose dolphins living at six different facilities, from the Brookfield Zoo near Chicago to Dolphin Quest in Bermuda.

The dolphins at these sites are part of a captive-breeding programme and they have periodically spent time together going back many years, complete with fully-verified records.

During the study, Dr Bruck would play a recording of signature whistles of a stranger that a dolphin had never heard before. After repeating the call many times, the dolphin would quickly show signs that it is bored with the sound of another dolphin it had never met, he said.

Dr Bruck then introduced the call of a dolphin they had once known, and measured its response and behaviour. "When they hear a dolphin they know, they often quickly approach the speaker playing the recording. At times they will hover around, whistle at it, try to get it to whistle back," Dr Bruck said.

In one notable example, for instance, a female named Allie living at Brookfield Zoo recognised and responded to a recorded call of female called Bailey, now living in Bermuda, which had shared a pool with Allie 20 years and six months previously when they both lived at Dolphin Connection in Florida Keys, he said.

Dolphins are thought to live for about 20 years on average in the wild, although they are known to live as long as 45 years in captivity. It is possible that they social memory for signature whistles could last their lifetime, Dr Bruck said.

This is the longest, scientifically-tested social memory in animals, matched only by the anecdotal reports of elephants being able to recognise their mothers after 20 years of separation.

A study published earlier this year by researchers at the University of St Andrews found that dolphins not only recognised each other by their whistles but often mimic a close companion's unique whistle in an attempt to get them to respond.

"We know they use these signatures like names, but we don't know if the name stands for something in their minds the way a person's name does for us. We don't know yet if the name makes a dolphin picture another dolphin in its head," Dr Bruck said.