For years, neuroscientist Manfred Spitzer has researched the effects of digital media on our minds, and has concluded that digital media are harmful to the brain. They lead to abnormal development in young people and are a primary cause of burnout in adults. We spoke with him about how modern media can bring us forward and set us back.

Raquel Forster: Professor Spitzer, in books, lectures, and talk shows, you warn urgently against the digital dementia that affects children if they are exposed to computers, smartphones, or Playstations too early. I personally spend a large part of my workday in front of two computer screens. Should I be really worried about my mental fitness?

Professor Manfred Spitzer: No, you shouldn't. I like to compare it to mountain climbing: If you're already a mountain climber, you don't need to worry about your physical fitness, even if sometimes you drive to the base of the mountain or use other technical assistance. It's the same for people who use their intellect at work. They don't need to worry about their minds just because they use technology at the workplace. I'm more interested in drawing attention to the risks and side effects of computers. After all, if something has effects, it will also have side effects. My work is focused on children and young people, meaning those whose brains are still in the developmental stage. They need to interact with the real world to develop normally. The reason my book is entitled "Digital Dementia," although I'm targeting young people in particular, is because of the following – allow me to return to mountain climbing: When you descend the mountain later as an older person, the length of time it takes will depend on how high you ascended in the first place. If you walk from Mount Everest to the sea, it takes a lot longer than from a sand dune to the sea. "De-mentia" means "out of one's mind," and the more knowledge you have, the longer it will take to descend the mountain. So I think today's youth will have problems a few decades from now as a result of their media consumption.

You've said that outsourcing the thought process to machines is bad for the brain …

… Yes, of course. If you use a navigation device in the car and don't think about where you are, your car is leading the way and not your brain. Think about what happens to your brain then: It doesn't get any smarter. Quite the opposite: Connections, or parts of the brain that aren't used for longer periods of time, will deteriorate.

If you look at a modern trading floor of a major bank like Credit Suisse, it's hard to imagine a world without computers. Every trader is in front of a wall of at least six screens. Would investment decisions be better without these tools?

I don't think so, otherwise we wouldn't have them. Still, it's important to note the long-term impact of this type of work or lifestyle. If I'm an employee who feels like a slave to my environment, who is simply reacting, then I've lost control. Unfortunately, that's the subtext of digital media. They wake us up in the morning, they vibrate when we have to answer a message, and beep to remind us of an appointment. We always have to respond, meaning that we're no longer active. We're just passive. Many people refer to this phenomenon as "information overload," which is nonsense because the brain can't be overloaded. It just feels that way. And that feeling is identical to stress. Digital media increase stress: People feel at the mercy of their devices, which leads to burnout – all because digital media are slowly taking control. It's a very tricky mode of operation, but if you understand it, you can actively counteract it.

How, for instance?

By going offline. Being online 24/7 poisons the mind, as corporations such as Volkswagen have already realized. They insist that their employees go offline after regular working hours.

What else should CEOs do to keep their employees mentally fit?

Employees need to move. The best mental exercise is still physical exercise. You don't have to do crossword puzzles or Sudoku to keep your mind sharp. That's a myth. Movement is essential, because it helps nerve cells regenerate and the mind become more attentive. A variety of tasks at the workplace and breaks are important in order to disconnect and recharge our batteries. Nature is also very healing for the mind – and not just because of the fresh air. To put it simply, it makes us better people; we become more social. I think this aspect is also very important nowadays, because talking with one another is always completely different from "chatting" with one another. Once you understand that, then you'll realize that what we currently consider to be the perfect working environment is not really beneficial to our well-being.

Still, our free time is spent more and more in front of a screen …

… Yes, but if you do that, it's your own fault. If you spend your whole workday in front of the screen and then go home to watch TV all evening, you should know that's not good.

But does it really matter if I read the daily news on an electronic device or in an actual newspaper?

Studies have shown that it actually doesn't matter how you read it. I personally prefer an actual newspaper, but then I'm older (grins). Young people probably prefer their smartphones. The problem with electronic media is that they are always being improved: Pictures are replaced by videos, citations are replaced with hyperlinks, etc. So people click around more and read less. This means they retain less of what they read. It is said that "Reading makes you smarter." Today we need to add, "Reading makes you smarter, clicking around doesn't." This means that the knowledge of people who read the daily paper on an iPad, and who are always online, declines instead of improves because they're clicking around from page to page. So maybe an actual newspaper is better after all.

On the morning train, I'd say about 90 percent of the passengers are looking at a smartphone or tablet. How should these people be spending their time instead?

They could read a book, for example. Mornings are a very valuable time because our minds are very alert and agile. So if you're just checking emails and yesterday's news then, you're not taking advantage of this valuable time. That's a real shame. You could do those tasks in the evening or when you're having a 2:00 p.m. slump.

Without computers, trains couldn't move, planes couldn't fly, we wouldn't have electricity, and so on. Are you nostalgic for the old days?

No, not at all. I agree that we need computers. I just want to warn about the risks and side effects they can have. For example, in China, third graders learn how to write on a computer. The Chinese language has thousands of characters, but does that mean the Chinese have keyboards the size of a dining room table? No, because for 20 years the Chinese have been using a method by which they just type the sound of the word into the computer. For example, "Li" can mean pickle, gross national product, or many other things. The computer then shows the corresponding characters that could mean "Li." The pupils click on the word they want and keep typing. That may sound great, but a Chinese author did a reading test about a year ago and determined that more than 50 percent of fifth graders can't read. He conducted this reading test with third to fifth graders. Among the third graders, two to seven percent could not read – which is in the normal range. In the fourth grade, this number jumped to more than 42 percent and in the fifth grade it was more than 50 percent. Related studies showed that the more a pupil used this new method, pinyin, the less he or she could read and write. In other words, if we teach third graders in China to use modern media, the side effect is that a year later, half of them can't read anymore!

So what do new media mean for children?

Fewer learning opportunities. Take the iPad: Some parents say their children are clever because they can use an iPad at age two. I can only tell these parents that they are making their kids stupid. Moving your hand over a smooth, contour-free surface with no structure is the stupidest motor skill and most boring sensory hand movement that you could do. It doesn't teach a two year-old's brain anything. Children need holistic experiences. Optical input must harmonize with acoustic and haptic input down to the last millisecond. Otherwise the brain gets confused and can't learn a thing. That's why computers are great for adults, but they are pure poison when it comes to brain development in children and youths. This means that if they're shooting monsters for three hours a day, then their brain becomes attuned to shooting. When I look at young people today who have no empathy for anyone and – take America for instance – shoot other people without a second thought, or record two people in a physical altercation instead of intervening, then we have a very strange young generation. It scares me to think that these people will someday be shaping our world.

We don't know what the world will be like in 30 years. Can adults even keep up with new technologies if they weren't exposed to them as children?

Nonsense. Compare it to alcohol, which has been part of our culture for thousands of years and saves lives every day in a medical context. Do we have alcohol aptitude training in preschools? Or do we give children and youths schnapps so that they can gradually get used to alcohol? Of course not. We know today that it's inappropriate – but in the Middle Ages it was different. Today we sit them in front of the TV to keep them quiet, and in 20 years we'll realize that this is just as bad as giving them alcohol was in the Middle Ages. As further proof that computers have no place in classrooms, googling is so easy that anyone can do it after you show them once. You click on the browser, enter a word, click on "Google Search" and get 10,000 hits. What you really need in order to google is (background) knowledge. If you don't know anything, you won't know what to do with all the results Google throws at you. So your background knowledge is like a filter that lets you separate the wheat from the chaff. Contrary to belief, this background knowledge doesn't come from googling. Psychologists from Columbia and Harvard found that content from Google is retained for the least amount of time because our brains think we can access this information whenever we want. This is different from newspapers or books, where we retain much more knowledge. So if you really want kids to learn how to use Google at school, there's one thing to avoid: Google. Kids don't need Internet 101 or media skills. They need much more background knowledge.

So what's the ideal age to introduce modern media?

Let me ask you this: What's the ideal age to introduce alcohol? Because the brain is still developing at age 15, alcohol is inadvisable. The same is true for computers. A Pisa study of 250,000 15-year olds showed that having computers in their bedrooms was bad for their educational development.

You mean in terms of mental development or potential addiction?

I primarily mean mental development. The Pisa study didn't research addictive behaviors. Still, it's been proven that the potential for addiction is very high particularly among 12-to-16 year olds. Half a million young people have an internet addiction in Germany. In South Korea, it's 12 percent of all youths – the average media use is even higher there. This data comes from the ministry of health and it's alarming when you think about it. As a psychiatrist, I've seen these people. They are a wreck. Half a million wrecks is a significant portion of our young people. No society can afford that. This is why the minimum age for media consumption should be between 15 and 18. This doesn't mean I'd never watch a movie with a five year-old or put him in front of the computer to try it out. But new media aren't good for preschoolers, grade schoolers, or even kids in junior high. Studies show they do the brain more harm than good.

What's your relationship to electronic devices?

I need them for work and I even have a navigation device. But I still always try to know where I am and not just blindly follow the GPS while driving. I don't have a TV, because it would make me crazy and I think TV is incredibly boring. I also make a conscious effort to switch off and not be online all the time. Especially in the mornings, when the mind is really fit, I like to have peace and quiet to work. Those are important things to keep in mind when you're busy, otherwise you'll become ineffective.

What about your kids?

Of course they complained when we got rid of the TV. Eventually they thanked us for it, though. I'm sure other parents have the same experience: Their children will thank them when they're 20 or 22 years old. So I can only encourage others. This stupid idea that you must have a TV because other people have one is also bandied about by the lobby. For example, to say that kids can't get on Facebook without a smartphone, and will therefore be bullied and become outsiders. Or that high schoolers need laptops or they'll lag behind. It's all nonsense. We know it's the children who spend a lot of time on Facebook or online in general that become outsiders, not the ones who don't have a laptop. The media lobby plays a lot on our fears. They make us worry that we'll fall behind or that we'll cause our kids to fall behind if they aren't allowed access to media. That's completely wrong, because the data indicates just the opposite. The rest is marketing by the big global companies. We mustn't leave our brains up to them, and we certainly mustn't leave our children's brains up to them.