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With the tiny screen bouncing around in front of us, tinny sound quality and frequent interruptions, watching a movie during a flight is hardly an immersive experience.

Yet, frequent fliers may have found themselves – or at least witnessed others – welling up at the most innocuous of films while on a long airline journey. Even lighthearted comedies such as Bee Movie, Bridesmaids and The Simpsons can trigger the water works in passengers who would normally remain dry-eyed if watching these on the ground.

Physicist and television presenter Brian Cox and musician Ed Sheeran have both admitted they can get a bit over-emotional when watching movies on aircraft. A new survey by Gatwick Airport in London found 15% of men and 6% of women said they were more likely to cry when watching a film on a flight than they would if seeing it at home.

One major airline has gone as far as issuing “emotional health warnings” before inflight entertainment that might upset its customers.

There are many theories about why flying might leave passengers more vulnerable to crying – sadness at leaving loved ones, excitement about the trip ahead, homesickness. But there is also some evidence that flying itself may also be responsible.

An emerging body of research is suggesting that soaring 35,000ft (10km) above the ground inside a sealed metal tube can do strange things to our minds, altering our mood, changing how our senses work and even making us itch more.