It’s becoming harder to concentrate. In The Shallows: What The Internet Is Doing to Our Brains, Nicholas Carr quotes a research project at Stanford University in which cognitive tests were given to a group of “heavy media multitaskers” and a group of “relatively light” multitaskers. The heavy multitaskers were much more easily distracted by “irrelevant environmental stimuli” and less able to maintain their concentration. On the plus side, young people today have skills their predecessors lacked. They are adept at finding and filtering information, responding to stimuli and doing fast, incisive analysis. As “digital natives” who have grown up with the Internet, they are used to technological change, while “digital immigrants”, who grew up before the Internet, find it hard to keep up.

An experiment led by UCLA’s Gary Small showed how the web can change our brains in a matter of hours. Twelve experienced web users and 12 novices used Google while their brains were scanned. In the area called the dorsolateral prefrontal cortex, which deals with short-term memory and decision-making, the newcomers showed hardly any activity, whereas the web veterans lit up the screen. Six days later, after the novices had been told to spend an hour a day online, the two groups’ brain scans were virtually identical.

Constant communication makes you anxious, especially if you monitor emails, text messages, status updates and BlackBerry Messenger as closely as the average teenager. It creates “a terrific anxiety about being out of the loop”, says psychotherapist Michael Hausauer. There is even an acronym for this phenomenon: FOMO — “fear of missing out”.

A Stanford study found that the digital generation are learning to socialise differently. Researchers discovered students prefer to text a classmate down the hall in their dormitory rather than talk in person because it is “less risky” and “less awkward”. So they don’t learn how to read facial expressions or navigate “real world” social situations.

A survey published earlier this year found that four out of five 18 to 30 year-olds are unable to navigate without the aid of a satnav device. Other basic practical skills are vanishing too. A US study in 2006 of 1.5 million 16 and 17 year-olds found that only 15 per cent used joined-up writing. Most used block capitals, like a child.

Thanks to the digitisation of our contact books, we can no longer remember phone numbers. According to recent research, one in three Britons under 30 can’t even remember their own number. And it is now so easy to find information via Google that we’re getting worse at remembering any facts at all. Four experiments published in the journal Science in 2011 found that people struggle more than ever before to retain information.

Many studies have shown the Internet is addictive. One by the Chinese Academy of Sciences in Wuhan demonstrated brain changes in heavy web users similar to those hooked on drugs or alcohol. Other studies have shown changes in the prefrontal cortex, the part of the brain responsible for decision making and self-control. One psychiatrist has identified a condition he calls Facebook Addiction Disorder. Symptoms include letting Facebook interfere with your sleep or work, spending more than one hour a day on it and being filled with fear at the thought of deleting your account.

The types of friends we make is changing. Smartphone apps now send you an alert when they detect people nearby with whom you share interests. As this phenomenon intensifies, our circle of friends will increase but those friends will come from a narrower cross-section of society. We’ll become more tribal and less exposed to people with interests different from our own.

Talking in 2010, Mark Zuckerberg, the founder of Facebook, announced that privacy is no longer a “social norm”. In the future, data on our habits and movements — where we’ve been and what we’ve done — will be available to anyone who wants to know. Thanks to image-recognition software, we’ll be able to identify anyone who we point a phone at; when we shop online, prices will be tailored according to our income and willingness to pay; and when we go to the airport, aviation authorities will know so much about the minutiae of our lives it will no longer be necessary for us to queue for security. In fact, there is so much personal data on the web that Eric Schmidt, the co-founder of Google, has warned that teenagers might be forced to change their names one day in order to escape their cyber past.

The way we communicate is making us worse people to be around. We are ruder. An Ofcom report found that 51 per cent of adults and 65 per cent of teenagers have used their smartphone while socialising. Baroness Susan Greenfield says: “We may be in danger if we are creating an environment for the next generation where a premium isn’t put on eye contact, body language and hugging.”

Even the way we die is changing: “digital estate handling” is a boom industry. Companies such as LegacyLocker store clients’ passwords to their email, eBay or social media accounts and give these to a designated loved one after the client dies. Other sites create customised online grave sites. Loved ones can add “tribute gifts” such as roses, candles and stuffed animals while mourners can access photos and videos in a “Memory Book”.