Curious Cases

11 year old Esther visualises days of the week in a kind of 3D structure. It’s something called ‘synaesthesia’ and she wants to know why it happens - and why other people don’t experience things the way she does. Hannah Fry and Dara Ó Briain explore the vibrant and varied ways different people experience the world, from the man who tastes individual words - including all the stops of the tube - to the composer who sees music in shapes and colours. And along the way, they figure out why Mozart is white wine while Beethoven is red. Contributors:Professor Julia Simner: Professor of Psychology,University of Sussex Professor Jamie Ward: Professor of Cognitive Neuroscience, University of Sussex James Wannerton, President of UK Synaesthesia Association CoriAnder: electronic music producer Producer: Ilan Goodman Executive Producer: Alexandra Feachem A BBC Studios Audio Production

It’s sometimes said that timing is everything and this week the pair investigate the mystery of rhythm, discovering why some of us might be better at staying in tempo.From the daily cycle of dawn and dusk to sea tides and circadian clocks, rhythm governs many aspects of our lives, and cognitive psychologist Dr Maria Witek says it makes sense we also place great importance on its presence in music. She specialises in ‘groove’, or the feeling of pleasure associated with moving to a beat – and it’s not just something the dancers among us enjoy; groove has even been used to treat patients with Parkinson’s Disease.Neuroscientist Professor Nina Kraus has studied drummers’ brains and found their neurons fire with more precision. She explains that teaching kids rhythm can improve their language and social skills. But no need to take her word for it, because Skunk Anansie’s drummer Mark Richardson is in the studio to put Hannah to the test. Can she handle a high hat at the same time as a snare?Contributors: Dr Maria Witek, University of Birmingham Professor Nina Kraus, Northwestern University Mark Richardson, drummer with Skunk Anansie Producer: Marijke Peters Executive Producer: Alexandra Feachem A BBC Studios Audio Production

9 year old listener Koby sends Hannah and Dara on a mission to find the shiniest thing in the world. And so they enter a world of mirrors… The journey takes them into the subatomic goings on of shiny metal surfaces, where electrons waggle and dance and send light waves back at *just* the right angle. Our curious duo play with an astonishingly reflective plastic film that can be found hidden in devices we all use. And they probe the mysterious power of refraction, harnessed to make the $2 million mirrors which reflect the lasers at the huge LIGO experiment. And everyone ponders the surprisingly reflective properties of a pint in space. Contributors:Dr Felix Flicker: University of Bristol, author of The Magick of Matter Professor Stuart Reid: University of Strathclyde Quinn Sanford: optical engineer from 3M GariLynn Billingsley: Optical Sciences Group Leader at LIGOProducer: Ilan Goodman Executive Producer: Alexandra Feachem A BBC Studios Audio Production

Would you eat food that fell on the floor? That’s the question Hannah and Dara are getting their teeth into this week as they put the so-called ‘5 second rule’ through its paces. For some people it’s 3 seconds, and for others its 10 – especially if it involves a dropped ice cream and a screaming child. But microbiologist Don Schaffner says there’s no safe amount of time to leave food on the floor if you’re planning to eat it. And while you might think buttered toast would pick up the biggest number of bugs, it may surprise you to hear that wet foods like watermelon are actually the worst when it comes to attracting harmful bacteria. If all this is putting you off your dinner, the bad news is that the rest of your kitchen is also a microbiological minefield. Research shows nearly 70% of us keep our fridges are the wrong temperature, which sparks a lively discussion about whether it’s ever safe to reheat rice. For home hygiene guru Sally Bloomfield it’s all a question of being a bit more clever about the kind of germs we expose ourselves to and weighing up risks. Contributors:Dr Don Schaffner: Rutgers University Dr Ellen Evans: Cardiff Metropolitan University Professor Sally Bloomfield: International Scientific Forum on Home HygieneProducer: Marijke Peters Executive Producer: Alexandra Feachem A BBC Studios Audio Production