Ballet dancers’ brains adapt to stop them going dizzy

Years of training in “spotting”, the technique of quickly and repeatedly bringing your gaze to two specific points in front and behind you, certainly helps, but new research suggests that the brain’s ability to adapt plays a powerful role.

If you’ve ever tried spinning in circles while looking up to the sky, you’ll know the accompanying dizziness that can follow. But what stops ballet dancers, who pirouette endlessly for a living, from falling into each other like a set of dominoes?

Years of training in “spotting”, the technique of quickly and repeatedly bringing your gaze to two specific points in front and behind you, certainly helps, but new research suggests that the brain’s ability to adapt plays a powerful role. And it could help better treat and diagnose people who suffer from chronic dizziness.

Neuroscientists at Imperial College London recruited 29 female ballet dancers and spun them around in a chair in a dark room. When the chair was stopped, the dancers were asked to turn a lever to indicate how quickly they still felt they were spinning. This measured their perception response to dizziness. Eye reflexes – the quick flicking of the eyes from moving around rapidly – were also measured. In normal people, these two responses correlate well, but in the dancers there appeared to be an uncoupling: while their eye reflexes kept going, their perception response fell.

A group of 20 female rowers, who were similar in age and fitness, were also recruited as a control group. Brain scans were then taken to analyse the brain structures of all the individuals.

Powerful resistance

In cases of chronic dizziness, tests are usually taken of the vestibular organs in the inner ear. These fluid-filled organs use tiny hairs to sense the movement of the fluid, which in turn send signals to the brain. The continued movement of fluid explains one of the reasons you can continue to feel dizzy after you’ve stopped moving. But this doesn’t go far enough to explain dizziness in chronic suffers, said Barry Seemungal, co-author of the study, published in Cerebral Cortex.

“We measured sensation perception and eye reflexes and found dancers were much more resistant to non-dancers,” he said. “In the rowers, sensation correlated very well to reflexes, but in dancers the two were not correlated – they had de-coupled. In a person with chronic dizziness, the duration of their perceptual response is much longer; there’s a disproportionately higher reaction compared to a dancer who shows powerful resistance.”

An MRI scan then looked at the amount of grey matter (the bit that calculates) and the white matter (the part of the brain that makes connections) in the cerebellum. This also threw up differences between dancers and non-dancers.

“A statistical comparison between brain structures showed that in dancers an area of the cerebellum was smaller than in the rowers. This part of the brain also known to be involved in processing signals from the ear. And the more experienced the dancer, the smaller it is. The cerebellum can process signals that are then sent to areas of the brain linked to perception. In dancers it reduces the flow of signals – it acts like a gate.”

The researchers then looked at the cerebral cortex, which is associated in perception, and found stronger white matter in the control group. “More white matter means you’re more likely to be dizzy – in dancers we didn’t see it,” Seemungal said.

Seeing is believing

So how can these findings help people with chronic dizziness? For a start, we now have recognition that the brain is the organ that controls balance and, crucially, that it’s able to adapt.

“Traditional testing considers the ear as the organ of balance,” Seemungal said. “I’m a neurologist so I consider it as the brain.”

“The brain takes in lots of different information to make an assessment and compensates if it needs to. The ear is one source, vision is another. If you hear a noise to the right and move your head to look at it, your brain combines the estimates and places greater weight on the more reliable, in this case the eye.”

“But vision can be ambiguous – for example when you’re sat on a train and another one moves and you think you’re the one moving. As a general principle the brain prioritises visual motion over vestibular organs [the ear]. Another example is the ventriloquist’s doll, it combines the auditory and visual inputs but relies more on the visual so you think it’s the doll that’s talking.”

“If your vestibular organs aren’t working well, your brain won’t trust them and even trivial visual stimuli can trigger a dizzy sensation. But traditional testing relies on testing the vestibular organs, which might indicate nothing is wrong.”

People with chronic dizziness can be treated for underlying causes but also longer-term physio treatment. Depending on the form of the condition, this can include exposing them to self-motion (the swaying we all do but don’t notice if we don’t suffer from dizziness) and visual motion to get the brain more habituated.

One lucky find (for the researchers anyway) was that one of the dancers involved in the study later went on to develop chronic dizziness. This enabled the team to test her against their original findings. They found that although her reflex functions had remained the same, her perception response had become stronger.

Professor Nicky Clayton, a Professor of Comparative Cognition at Cambridge and Scientist in Residence at Rambert, the contemporary dance company, said: “As a dancer you learn tricks that allow your body to move in very flamboyant ways but without losing control. One of the tricks I learned was that when you get that sense of spinning, you use your core muscles to pull up; and that you’re disengaging with that feeling of fluidity and creating a stabilising energy.

She added: “Dancers think in very abstract ways … The way in which the brain talks to the cognitive system, whether through its plasticity or psychologically, is more than just spotting. Spotting helps you to focus but it’s not the only thing.”

Simon Lloyd, an ENT specialist, said: “The tests could potentially be useful because at the moment we have no effective way of testing how well parts of the balance system within the brain are working. Testing this would also allow us to measure how people are responding to treatment.”

The Conversation

This article was originally published at The Conversation. Read the original article.

Dancers of Cuba national ballet perform during a rehearsal for Swan Lake in Madrid in 2009. Photo: AFP/Getty Images

Jo Adetunji is the commissioning editor for health and medicine at The Conversation UK.

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Poldark is the latest show to throw in a lazy, irresponsible rape scene

It’s particularly dangerous to present a scene like this as consensual, as the writers insist it is.

So Poldark has become the latest show to throw in a lazy, irresponsible rape scene to spice things up. We’ve sat through them in outrage-courting Game of Thrones, in cosy Sunday night drama Downton Abbey, and even at the opera. Now, they’ve come to BBC period adaptations, too.

This is how the scene plays out (a detailed description of the events leading up to the rape follow):

Poldark (Aidan Tuner) turns up at his friend Elizabeth’s bedroom door in the middle of the night, in a rage. She suggests he come back tomorrow morning. He refuses. She suggests they relocate downstairs. He refuses. She suggests he should not be in her bedroom. He refuses to leave, and shuts the door behind him.

They argue about Elizabeth’s plan to marry an enemy of Poldark’s, a decision that disgusts him. She asks him to leave, again. “I’m sorry you feel like this, but I cannot help it,” she tells him. “Oh, you’ve never been able to help anything, have you?” he says, mockingly, adding, “well, perhaps you can’t help this either,” kissing her forcefully before she pushes him off her.

Poldark threatens her, approaching her again as he insists, “I oppose this marriage, Elizabeth. I’d be glad of your assurance that you will not go through with it.” She says again that she will be married. Poldark kisses her again against her will. She tells him she hates him. “You would not dare,” she pleads, looking at the bed. “I would, and so would you,” he says. He pushes her onto the bed. You can guess the rest.

Of course, this is a rape scene. Some say it isn’t – because Elizabeth shows signs of enjoying the sex, and she’s nice to Poldark the next morning, because she has (or has had) feelings for him. None of these things are relevant. Poldark verbally pressured and physically forced a woman who was refusing to have sex with him. That’s rape.

It’s particularly dangerous to present a scene like this as consensual, as the writers and cast insist it is. Andrew Graham, the son of Poldark novelist Winston Graham, who was a consultant on the BBC's current screen adaptation, said:

“There is no ‘shock rape’ storyline. The only way to judge what my father intended is to read the novels as a whole. Doing so it becomes clear, from earlier scenes as well as from Elizabeth's immediate reactions and later mixed emotions, that what finally happened was consensual sex born of long-term love and longing. It was, as Aidan Turner has put it, ‘unfinished business emotionally’.”

His opinion was supported by Poldark screenwriter Debbie Horsfield as well as Turner – who said the scene “seems consensual”.

This is not how consent works. Consent is not something you can assume based on “earlier scenes”. And it’s certainly not something you can retrospectively achieve based on the “immediate reactions” or “later mixed emotions” of someone you forced to have sex with you. That’s just you attempting to justify the fact that you raped someone.

The idea that Poldark knows Elizabeth so well that he knows what she truly wants (sex with me, the man of her dreams, duh!!) might seem romantic. But no love is so great that it imbues the lover with the ability to read minds. Implying that Poldark knew best peddles the dangerous myth that when women say no, they mean yes. Beliefs like this create rapists. The only way to know what someone wants is to ask them, and to listen to what they say. Elizabeth said no.

Adapting period material can be tricky – not least in its presentation of women, gender dynamics, and sex. The Poldark books are from the Fourties, and set in the eighteenth century. It’s a miserable state of affairs when the understanding of consent presented on primetime television, in 2016, is as dated.

Anna Leszkiewicz is a pop culture writer at the New Statesman.