Out on a sunny Berlin balcony, Tim Keeley and Daniel Krasa are firing words like bullets at each other. First German, then Hindi, Nepali, Polish, Croatian, Mandarin and Thai – they’ve barely spoken one language before the conversation seamlessly melds into another. Together, they pass through about 20 different languages or so in total.

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Back inside, I find small groups exchanging tongue twisters. Others are gathering in threes, preparing for a rapid-fire game that involves interpreting two different languages simultaneously. It looks like the perfect recipe for a headache, but they are nonchalant. “It’s quite a common situation for us,” a woman called Alisa tells me.

It can be difficult enough to learn one foreign tongue. Yet I’m here in Berlin for the Polyglot Gathering, a meeting of 350 or so people who speak multiple languages – some as diverse as Manx, Klingon and Saami, the language of reindeer herders in Scandinavia. Indeed, a surprising proportion of them are “hyperglots”, like Keeley and Krasa, who can speak at least 10 languages. One of the most proficient linguists I meet here, Richard Simcott, leads a team of polyglots at a company called eModeration – and he uses about 30 languages himself.

With a modest knowledge of Italian and some rudimentary Danish, I feel somewhat out of place among the hyperglots. But they say you should learn from the best, so I am here to try to discover their secrets.

When you consider the challenges for the brain, it’s no wonder most of us find learning a language so demanding. We have many different memory systems, and mastering a different tongue requires all of them. There’s procedural memory – the fine programming of muscles to perfect an accent – and declarative memory, which is the ability to remember facts (at least 10,000 new words if you want to come close to native fluency, not to mention the grammar). What’s more, unless you want to sound like a stuttering robot, those words and structures have to make it to the tip of your tongue within a split second, meaning they have to be programmed in both “explicit” and “implicit” memory.

Speaking extra languages delays dementia by five years or more

That tough mental workout comes with big payoffs, however; it is arguably the best brain training you can try. Numerous studies have shown that being multilingual can improve attention and memory, and that this can provide a “cognitive reserve” that delays the onset of dementia. Looking at the experiences of immigrants, Ellen Bialystok at York University in Canada has found that speaking two languages delayed dementia diagnosis by five years. Those who knew three languages, however, were diagnosed 6.4 years later than monolinguals, while for those fluent in four or more languages, enjoyed an extra nine years of healthy cognition.

Those lasting benefits are a stark contrast to the failure of most commercial “brain training” games you can download – which generally fail to offer long-term improvements in memory or attention.

Learning a new language as we age is easier than you might assume

Until recently, however, many neuroscientists had suggested that most of us are too old to reach native-like fluency in a fresh language; according to the “critical period hypothesis”, there is a narrow window during childhood in which we can pick up the nuances of a new language. Yet Bialystok’s research suggests this may have been exaggerated; rather than a steep precipice, she has found that there is a very slight decline in our abilities as we age.

Certainly, many of the hyperglots I meet in Berlin have mastered languages later in life. Keeley grew up in Florida, where he was exposed to native Spanish speakers at school.  As a child, he used to tune into foreign radio stations – despite not being able to understand a word. “It was like music to me,” he says. But it was only as an adult that he started travelling the world – first to Colombia, where he also studied French, German and Portuguese at college. He then moved on to Switzerland and Eastern Europe before heading to Japan. He now speaks at least 20 languages fluently, almost all of which were learnt as an adult. “The critical period hypothesis is a bunch of crap,” he says.

The question is, how do hyperglots master so many new tongues – and could the rest of us try to emulate them? True, they may just be more motivated than most. Many, like Keeley, are globe-trotters who have moved from country to country, picking up languages as they go. It’s sometimes a case of sink or swim.

Yet even with the best intentions, many of us struggle to speak another language convincingly. Keeley, who is currently writing a book on the “social, psychological and affective factors in becoming multilingual”, is sceptical that it’s simply a question of raw intelligence.  “I don’t think it’s a major factor, although it does make it faster to have the analytical ability,” he says.

Cultural chameleons

Instead, he thinks we need to look past the intellect, into the depths of our personality. Keeley’s theory is that learning a new language causes you to re-invent your sense of self – and the best linguists are particularly good at taking on new identities. “You become a chameleon,” he says.

Psychologists have long known that the words we speak are entwined with our identity. It’s a cliche that French makes you more romantic, or Italian makes you more passionate, but each language becomes associated with cultural norms that can affect how you behave – it could be as simple as whether you value outspoken confidence or quiet reflection, for instance. Importantly, various studies have found that multilingual people often adopt different behaviours according to the language they are speaking.

Different languages can also evoke different memories of your life – as the writer Vladimir Nabokov discovered when working on his autobiography. The native Russian speaker wrote it first in his second language, English, with agonising difficulty, finding that “my memory was attuned to one key – the musically reticent Russian, but it was forced into another key, English”. Once it was finally published, he decided to translate the memoirs back into the language of his childhood, but as the Russian words flowed, he found his memories started to unfurl with new details and perspectives. “His Russian version differed so much he felt the need to retranslate to English,” says Aneta Pavlenko at Temple University in Philadelphia, whose book, The Bilingual Mind, explores many of these effects. It was almost as if his English and Russian selves had subtly different pasts.

Resisting the process of reinvention may prevent you from learning another language so well, says Keeley, who is a professor of cross-cultural management at Kyushu Sangyo University in Japan. He recently ran a survey of Chinese speakers learning Japanese to examine their “ego permeability” – with questions such as “I find it easy to put myself in other’s shoes and imagine how they feel” or “I can do impressions of other people”, and whether you can change your opinions to suit the people you are near. As he suspected, the people who score highly on these traits had much greater fluency in their new language.

It is not just about the amount of time spent learning and using languages

How come? It’s well known that if you identify with someone, you are more likely to mimic them – a process that would effortlessly improve language learning. But the adopted identity, and the associated memories, may also stop you from confusing the language with your mother tongue – by building neural barriers between the languages. “There must be some type of home in your mind for each language and culture and the related experiences, in order for the languages to stay active and not get all mixed together,” Keeley says. “It is not just the amount of time spent learning and using the languages. The quality of the time, in terms of emotional salience, is critical.” Indeed, that might explain why Keeley could switch so effortlessly between those 20-odd languages.

Of all the polyglots, Michael Levi Harris may demonstrate these principles the best. An actor by training, Harris also has an advanced knowledge of 10 languages, and an intermediate understanding of 12 more. Occasionally, his passion has landed him in some difficulty. He once saw an online ad for a Maltese meet-up. Going along, he hoped to find a group of people from Malta, only to walk into a room full of middle-aged women and their white lap dogs – an experience he recently relayed in a short film The Hyperglot. You can see a trailer below.

When I meet him in a cafe near the Guildhall School of Music and Drama in London, he effortlessly slips into a rather posh, “received pronunciation” English accent, despite being a native New Yorker. As he does so, his whole posture changes as he melds into the new persona. “I’m not really trying to consciously change my character or my persona. It just happens, but I know that I am suddenly different.”

Importantly, Harris thinks that anyone can learn to adopt a new cultural skin in this way – and he has a few tips for how to begin, based on his experiences of acting. The important thing, he says, is to try to imitate without even considering the spelling of the words. “Everyone can listen and repeat,” he says. You may find yourself over-exaggerating, in the same way that an actor may be a little over-the-top in their performance to start with – but that’s a crucial part of the process, he says. “In acting first, you go really big, and then the director says OK, now tone it down. And you do the same with a language.” He also suggests looking carefully at things like facial expressions – since they can be crucial to producing the sounds. Speaking with slightly pouted lips instantly makes you sound a little bit more French, for instance.

Finally, he says you should try to overcome the embarrassment associated with producing "strange" noises – such as the guttural sounds in Arabic, for instance. “You have to realise it’s not foreign to us – when you are disgusted, you already say ‘eugh’. And if you acknowledge and give your subconscious permission to do it in speech, you can make the sound.” That may sound a little silly, but the point is that all this should help you to get over your natural inhibitions. “It’s all to do with owning the language, which is what actors have to do to make the audience believe that these words are yours. When you own words you can speak more confidently, which is how people will engage with you.”

There’s one big factor that stops people learning languages efficiently…

Even so, most agree that you shouldn’t be too ambitious, particularly when starting out. “If there’s a single factor that stops people learning languages efficiently, it’s that we feel we have to be native-like – it’s an unreachable standard that looms over us,” says Temple University’s Pavlenko. “The ease of expression is what matters to me a lot – finding a better way to express myself, colloquially.”

Along these lines, you should also practice a little and often – perhaps just for 15-minute stints, four times a day. “I think the analogies with exercise are quite good,” says Alex Rawlings, who has developed a series of polyglot workshops with Richard Simcott to teach their techniques. Even if you are too busy or tired to do serious study, just practising a dialogue or listening to a foreign pop song can help, says Simcott.

In the UK, Australia and US, it is easy to believe that we don’t need to make that effort. Indeed, before I met the hyperglots, I had wondered if their obsession merited the hard work; perhaps, I thought, it was just about bragging rights. Yet all of the hyperglots I meet are genuinely enthusiastic about the amazing benefits that can only be achieved by this full immersion in different languages – including the chance to make friends and connections, even across difficult cultural barriers.

Harris, for instance, describes living in Dubai. “As a Jewish person living in the Middle East, I faced challenges. But it turns out that one of my best friends was from Lebanon,” he says. “And when I moved away, he said ‘when we first met I didn’t think I could be friends with you and now you’re leaving, I’m distraught’. It’s one of the most precious things to me.”

As Judith Meyer, who organised the gathering in Berlin, tells me, she saw Ukrainians and Russians, Israelis and Palestinians all conversing at the gathering. “Learning another language really does open up whole new worlds.”

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