First Bite: How We Learn to Eat. Bee Wilson

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СКАЧАТЬ style="font-size:15px;">      The way our brains interpret flavours speaks to the human love of patterns. Professor Shepherd and colleagues have done experiments using fMRI and other brain scanning technologies to show that different flavours register as different patterns in the brain. It is startling to see scans of these flavour maps and realize that there is a separate place in our brains for bananas and Cheddar cheese or that strawberries and sugar show up as dots in similar locations. The way our brains map flavour is similar to the way that we perceive visual images. When we ‘see’ something, what we are actually doing is creating an abstract 2D representation of it, with some features enhanced and others suppressed. By the same token, when we put food in our mouths, the flavour molecules that drift to our nose are turned into abstract patterns in the brain. These patterns help us to recognize the food when we taste it again. Our olfactory receptors give different patterns to the sweet and the savoury; the rotten and the fresh. The receptors also modify the patterns depending on what is happening in the rest of the body: whether we are happy or depressed or nauseous.

      Through these patterns, our brains make sense of the bewildering world of flavour. Take umami, the so-called fifth taste, which corresponds to the savoury qualities in meat, cheese and certain vegetables such as tomatoes or broccoli. Umami is what gives mushrooms their oomph and the reason it’s so hard to stop pouring gravy on your potatoes. We all have neurons that are specifically tuned to umami. Yet by itself, umami – which is made in artificial form as MSG – doesn’t really taste of much. It is only in conjunction with other flavours that it becomes delicious. We can see this from neuroimaging studies. When glutamates are tasted in conjunction with a savoury vegetable odour, they generate far more brain activity than when the two flavours are tasted separately. The whole is more than the sum of its parts. This makes sense. Our brains are smart enough to see that a dish of Asian greens with soy sauce warrants a more sizeable flavour image than the same greens and soy sauce eaten separately.

      What is most significant about our flavour images is the way that they lead to what scientists call ‘images of desire’. Once we have a memory in our heads of a flavour we love, we build up ‘images of desire’ as we seek to acquire it again. In 2004 researchers put subjects on a bland diet and asked them to imagine their favourite foods. Just thinking about these beloved dishes created a response signal in the hippocampus, insula and caudate – the same areas of the brain that are activated during drug craving. Canadian researchers found that people who described themselves as ‘chocolate cravers’ showed different brain activity when eating chocolate than self-diagnosed non-cravers. The cravers’ brains continued to respond favourably to pictures of chocolate long after their bodies had reached a point of fullness. Neuroscience confirms that chocolate means more to some people than others.

      To anticipate pleasure in the next meal – something that can take up the greater part of the day, in my experience – is always a form of memory. And each mouthful recalls other mouthfuls you’ve eaten in the past. It stands to reason, therefore, that the flavour patterns in each of our brains are highly dependent on all the things we’ve tasted in the past, especially during childhood. Among North Africans settled in France, fresh mint tea, often served in ornate teapots, is a way of life. Children grow up with that familiar herbal steam rising from the table as adults sit and talk. A particularly refreshing mint tea is served in the courtyard of the Mosque in Paris, a tranquil place to retreat on sweltering days in the city.

      For French Algerians, mint tea is imprinted on the mind, in a way that doesn’t hold true for the non-African French population. In 2009 a group of subjects, half of them ‘Algerian-French’ and half of them ‘European-French’ were asked to smell mint and say what they thought of it. All of them – French or Algerian – found it pleasant and all of them correctly identified it as mint. But when gold electrodes were attached to the scalp, the Algerians showed a significantly greater level of neural activity in response to the mint than the Europeans. Because of the mint tea they drank at home, the smell induced a different cortical pattern in the brain. Put simply, mint was a flavour that resonated more with Algerians than the non-Algerians. This was an image their brains had already recognized many times before. If mint were a sound instead of a taste, you could say that the French heard the notes; but only the Algerians appreciated the music of it. Because their memories of it were more expansive, mint actually took up more of their brain.

      When we are unable to obtain the flavours we remember from childhood, it can give rise to longings so intense it is hard to think of anything else. The anosmia sufferers we met at the start of the chapter such as Marlena Spieler would confirm this: she hankers for the flavours that would make her feel ‘like Marlena’ again.

      Some of the most poignant examples of this flavour-yearning are the food obsessions of prisoners of war. When Primo Levi was imprisoned in a work camp near to Auschwitz called Buna, he remembered that fellow prisoners not only groaned in their sleep, but licked their lips: ‘They are dreaming of eating; this is also a collective dream … you not only see the food, you feel it in your hands, distinct and concrete, you are aware of its rich and striking smell.’

      Among memoirs by POWs of the Second World War, a common theme is not just hunger but the fevered memories it gave rise to of all the things they would eat again once they were free. Very seldom did they build these dreams about the grown-up food of sophisticated restaurants, but the food of childhood and of home: stodgy, filling and safe. One British ex-POW remembered dreaming two nights in a row about ‘omelettes and treacle pudding’. He also remembered his bitter disappointment on waking up, since ‘Either was as obtainable as a slice of the moon’.³¹

      Food obsession reached a particularly feverish pitch among European, American and Australian POWs in the Far East, where the mismatch between their rations of rice and the food they longed for was enough to make them slightly unhinged. Food historian Sue Shephard writes that most of the men in the Japanese camps ‘regressed to a childish state’. They all hallucinated about sugar: for the British it might be chocolate eclairs, suet puddings and steaming bowls of buttercup-yellow custard; for the Americans, Hershey bars, mother’s apple pie and every kind of layer cake, from devil’s food to coconut. Some men refused to join in the collective discussions of food because it was too painful to be reminded of how far they were from home, but for most of them, the crazy food talk became a survival mechanism to get through the endless days of boredom and brutality. A long-term POW recalled that after the first year and a half or so, the food talk had completely supplanted daydreams about women.

      Some men went so far as to write down elaborate menus and even recipes on scraps of paper. Film-maker Jan Thompson, who spent twenty years interviewing former American POWs for her 2012 documentary Never the Same, found that a common theme was writing down Thanksgiving menus, reconstructed from ‘memories of childhood gatherings’.³² All memory is a distortion, and in their half-starved state, these men constructed holiday menus more lavish than any of them can have actually enjoyed as a child. In Japan, Mess-Sergeant Morris Lewis felt oppressed by the responsibility of looking after his soldiers as well as himself. Sergeant Lewis kept himself ‘sane’ by writing down an extraordinary Thanksgiving dinner that included Virginia baked ham, fried rabbit, cranberry sauce, snowflake potatoes, candied sweet potatoes, buttered sweetcorn, buttered asparagus tips, green stuffed olives. Then, ‘Assorted Cookies’, ‘Assorted Nuts’, ‘Assorted Candies’, ‘Assorted Ice Cream’; also ‘Ass. Jams’ and ‘Fresh Ass. Fruit & Grapes’.

      This word ‘assorted’ is heart-rending, coming from a man whose diet has been reduced to abject monotony. Prison can famously expand the imagination. After all this time without biscuits, nuts, sweets and ice cream in any form, Sergeant Lewis was planning a meal where all these treats are freely offered in multiple varieties. He had returned to that old childhood pipe dream of being given free rein in a sweet shop.

      POW yearnings for childhood food were like an exaggerated version of the food nostalgia we all feel. What you are seeking to recover is not just the flavour in itself, but all the things that went with it: your family sitting round the table, the feeling of being СКАЧАТЬ