Songbirds need so-called “human language gene” to learn new tunes

Blogging on Peer-Reviewed ResearchThe nasal screech of Chris Tucker sound worlds apart from the song of a nightingale but both human speech and birdsong actually have a lot in common. Both infants and chicks learn their respective tongues by imitating others. They pick up new material most easily during specific periods of time as they grow up, they need practice to improve and they pick up local dialects. And as infants unite words to form sentences, so do songbirds learn to combine separate riffs into a full song. Songbirds need so-called “human language gene” to learn new tunes

Because of these similarities, songbirds make a good model for inquisitive neuroscientists looking to understand the intricacies of human speech. Zebra finches are a particularly enlightening species and they have just shown Sebastian Haesler that the so-called human ‘language gene’ FOXP2 also controls an songbird’s ability to pick up new material.

FOXP2 has a long and sordid history of fascinating science and shoddy science writing. It has been consistently mislabelled as “the language gene” and after the discovery that the human and chimp versions differed by just two small changes, it was also held responsible for the evolution of human language. Even though these claims are far-fetched (for reasons I’ll delve into later), there is no doubt that faults in FOXP2 can spell disaster for a person’s ability to speak.

Mutated versions cause a speech impairment called developmental verbal dyspraxia (DVD), where people are unable to coordinate the positions of their jaws, lips, tongues and faces, even though their minds and relevant muscles are in reasonable working order. They’re like an orchestra that plays a cacophony despite having a decent conductor and tuned instruments.

Brain scans of people with DVD have revealed abnormalities in the basal ganglia, an group of neurons at the heart of the brain with several connections to other areas. Normal people show strong activation of FOXP2 here and fascinatingly, so do songbirds. Haesler reasoned that studying the role of this gene in birds could tell him more about its human counterpart.

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Brain of the beholder – the neuroscience of beauty in sculpture

Blogging on Peer-Reviewed ResearchIs beauty simply in the eye of the beholder, or do all the beholders’ brains have something in common? Is there an objective side to beauty? Plato certainly seemed to think so. His view was that beauty was an inherent property that all beautiful objects possess, irrespective of whether someone likes it or not.

Brain of the beholder – the neuroscience of beauty in sculptureTo him, beauty in the world stemmed from an ideal version of Beauty that real objects can only aspire to. A biologist might instead suggest that the objective side of beauty stems from built-in predispositions for certain features, colours, shapes or proportions.

The opposing view is that art is a fully subjective enterprise and our preferences are shaped by our values and experiences. The real answer is likely to lie somewhere in the middle – after all, art students learn basic common skills such as proportion, perspective and symmetry before embarking on their own stylistic journeys.

Artists, critics and gallery visitors can argue about this question all they like, but some clearer answers have now emerged from three researchers in Italy, arguably the home of the some of the world’s most beautiful art. Cinzia Di Dio, Emiliano Macaluso and Giacomo Rizzolatti from the University of Parma have brought the tools of the modern neuroscientist into the debate.

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Delay not deviance: brains of children with ADHD mature later than others

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Attention-deficit hyperactivity disorder is the most common developmental disorder in children, affecting anywhere between 3-5% of the world’s school-going population. As the name suggests, kids with ADHD are hyperactive and easily distracted; they are also forgetful and find it difficult to control their own impulses.

brains of children with ADHD mature later than others

While some evidence has suggested that ADHD brains develop in fundamentally different ways to typical ones, other results have argued that they are just the result of a delay in the normal timetable for development.

Now, Philip Shaw, Judith Rapaport and others from the National Institute of Mental Health have found new evidence to support the second theory. When some parts of the brain stick to their normal timetable for development, while others lag behind, ADHD is the result.

The idea isn’t new; earlier studies have found that children with ADHD have similar brain activity to slightly younger children without the condition. Rapaport’s own group had previously found that the brain’s four lobes developed in very much the same way, regardless of whether children had ADHD or not.

But looking at the size of entire lobes is a blunt measure that, at best, provides a rough overview. To get an sharper picture, they used magnetic resonance imaging to measure the brains of 447 children of different ages, often at more than one point in time.

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Metabolic gene and breastfeeding unite to boost a child’s IQ

Blogging on Peer-Reviewed ResearchBreastfed babies have higher IQs if they have the ‘C’ version of the FADS2 gene.The nature-nurture debate is one of the most famous in biology, but its own nature has shifted substantially in recent years. We now know that genes and environment are not opposing agents that shape our lives separately, but partners walking hand-in-hand. More often than not, genes affect our bodies and behaviour by altering the ways in which we react to our environment.

Now, an international team of researchers have discovered a stark example of this gene-environment partnership. They found that breastfed children have higher IQ scores, but only if they have a certain version of a gene called FADS2.

The concept of IQ has been central to the nature-nurture debate for years, ever since studies in twins suggested that a large part of the variation in IQ scores could be explained through inherited genetic factors. Avshalom Caspi and Terrie Moffitt from King’s College London wanted to kill this tiresome debate finding a gene that affected IQ via the environment.

They chose to look at breastfeeding, as studies have mostly found that babies who drink their mothers’ milk have higher IQ scores, among other benefits. These higher scores persist into adulthood and across social classes. We also have a reasonable idea of how breastfeeding could affect brain development at a molecular level, and it involves fatty acids.

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Broken chains and faulty mirrors cause problems for autistic children

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Autistic children have sever social problemsYour brain has an amazing ability to predict the future. For example, if you see someone reach for a chocolate, you can guess that they’re likely to pick it up, put it in their mouths and eat it. Like most people, you have a talent for understanding the goal of an action while you see it being performed – in this case, you know that reaching for the chocolate is only a step towards eating it.

That may not sound very impressive, but as with many mental skills, it’s only apparent how complicated it is when you see people who can’t do it.

Autistic people, for example, find it incredibly difficult to relate to other people and this may, in part, be because they can’t understand the why of someone else’s actions. While a typical child would understand that a mother holding her hands out is readying for a hug, an autistic child might be baffled by the gesture.

Now, a new study by Luigi Cattaneo, Giacomo Rizzolatti and colleagues suggests that autistic people find it difficult to understand the purpose of an act because they cannot string together different actions into a coherent whole. And underlying this problem is a special group of nerve cells called mirror neurons.

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The neuroscience of optimism – how the brain creates a rosy outlook

In 1979, a crucified Eric Idle advised movie-goers to always look on the bright side of life. It seems that he needn’t have bothered. Psychological experiments have consistently shown that as a species, our minds are awash with a pervasive optimism.

We have an innate tendency to look on the bright side of life.We expect our future successes to overpower our past ones. Compared to an imaginary Joe Bloggs, we deem ourselves likely to live longer, more likely to have a successful career and less likely to suffer divorce or ill health. Even the most cynical of minds had a tendency for making similar, overconfident predictions.

Now, Tali Sharot and colleagues form New York University have pinpointed a neural circuit in the brain that generates this glass-half-full outlook.

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Doctors repress their responses to their patients’ pain

A new study shows that experienced doctors learn to control the part of their brain that allows them to empathise with a patient’s pain, and switch on another area that allows them to control their emotions.

Many patients would like their doctors to be more sensitive to their needs. That may be a reasonable request but at a neurological level, we should be glad of a certain amount of detachment.

In some doctors, being detached can be a good thing.Humans are programmed, quite literally, to feel each others’ pain. The neural circuit in our brains that registers pain also fires when we see someone else getting hurt; it’s why we automatically wince.

This empathy makes evolutionary sense – it teaches us to avoid potential dangers that our peers have helpfully pointed out to us. But it can be liability for people like doctors, who see pain on a daily basis and are sometimes forced to inflict it in order to help their patients.

Clearly, not all doctors are wincing wrecks, so they must develop some means of keeping this automatic response at bay. That’s exactly what Yawei Chang from Taipei City Hospital and Jean Decety from University of Chicago found when they compared the brains of 14 acupuncturists with at least 2 years of experience to control group of 14 people with none at all.

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