Britons are having less sex than they used to, says the latest medical research published in the Lancet: down to just under five times a month for the 16-44 age group and three times a month for the overall adult population. This represents a 20% decline since 2000.

The researchers have a few theories, including demographic changes – fewer people living together, more single-person households – along with an accusing finger pointed at the recession. According to one of the study leaders, Professor Kaye Wellings, rising numbers of unemployed people have reported low sexual function: "That is to do with low self-esteem, depression," she says. So that's another thing we can blame on the collapse of Lehman Brothers. Thanks to the banking crisis, there's a bonking crisis.

But the more intriguing suggestion is that at the other end of the economic scale, those in work are increasingly blurring the boundary between the office and home by taking their laptops and smartphones into the bedroom. The most obvious impact is simple: if people are still checking emails after midnight, that leaves little time to do anything else. They are too busy for sex. And if it's not work they're doing when they stare at the glowing screen but playing a game or checking Twitter, then they're still too distracted to notice the living, breathing person next to them.

But the impact goes deeper than that. I've written before of the evidence that the online world is already altering us sexually. Because of the ready availability of internet pornography, even the very young are now exposed to imagery they would once have had to work hard to seek out. Compared to the kind of hyper-sexuality on show in porn, it wouldn't be a surprise if, for many, the real thing feels like a disappointment – simply unable to match the dopamine hit available from the screen.

The intrusion of the smartphone into our lives works in other ways too. Another survey found one in 10 Americans used their iPhones or BlackBerries during sex, a figure that doubles among the young. What are they using them for exactly? Is it mainly as a camera, to produce a string of X-rated selfies? Or is something else going on?

The online adult performer who tweets as @chaosintended wrote a fascinating piece for Business Insider, arguing that the relationship we are developing with our smartphone has become almost erotically intimate, that we are confiding our innermost desires in those sleek, shiny gadgets. She raises the troubling notion of a new generation of human – a kind of cyborg that is part flesh, part electronic device. But she might be on to something. Note the case in Japan – where there has been a striking decline in sexual activity and where electronic devices enjoy a high degree of, ahem, penetration – of a man in his early 30s, still a virgin, who can only get sexually aroused if he watches female robots on a computer game similar to Power Rangers.

Perhaps I'm getting ahead of myself here. But the internet revolution is changing so much about us – our work, our memories, our homes – why wouldn't it change our sexuality too?