Susan Greenfield: The too-much-information society

Press a button, get a hit. Press again, get another. Sound like a lab rat pushing levers in some endless instant gratification feedback loop? Or just a heavy internet user?

Press a button, get a hit. Press again, get another. Sound like a lab rat pushing levers in some endless instant gratification feedback loop? Or just a heavy internet user?

Professor Susan Greenfield, a leading neuroscientist and director of the Royal Institution of Great Britain, wondered about the long-term risks of information technology use when she watched a fellow airline passenger become "almost addicted" to the touch screen in front of him. "It was just the thrill of touching something and getting a response," she says.

Greenfield, who is the author of The Private Life of a Brain, believes society's increasing use of IT, and particularly the internet and computer games, carries serious risks along with the well-known benefits. These risks include the potential loss of imagination, the inability to maintain a long attention span, the tendency to confuse facts with knowledge, and a homogenisation of an entire generation of minds. These risks could even actually change the physical workings of the brain, she says.

"Brain cells are networked to each other, and from one moment to the next there is this highly transient networking to different degrees. And the more the networking occurs, the more conscious you are," Greenfield says. "[That networking] is an electrical thing, where you can actually see a cohesive activity in a lot of brain cells - a bit like synchronised swimming.

"The tentacles [between brain cells] are the anatomical things that the electrical impulses rush down. Looking at the physical wiring of the brain tells you what is possible to connect to what, but it doesn't actually tell you what is communicating with what."

While heavy Net users who develop shortened attention spans will probably not have fewer connections between the brain cells, those links might well have a different layout.

"It's possible that [the brain cell connections] will not develop in the same configurations," Greenfield expands. "The tendencies with how they work together and the assemblies [of neurons] they form might be different."

Greenfield came to her conclusions when reading about the plasticity of the brain. The Oxford professor of pharmacology predicts that IT use and drugs, both illegal and legal, could have the two most dramatic effects on the human brain over the next century.

Does that mean the Net is some kind of "Substance D", the mass-produced and highly addictive drug at the centre of Philip K Dick's cult novel A Scanner Darkly? Not exactly. Greenfield says that while people can become addicted to computer games "in a gross and rather vague way", the internet and other forms of information technology are not like dangerous narcotics.

The risks are more subtle, she says, such as children confusing facts with knowledge. In the blitz of information available from the Net, young people without life experience might find it increasingly difficult to build filters and mental frameworks to place so many facts. "They start to drown in [facts] without having a cohesive framework in which to put that information."

Knowing a fact does not make someone "deeply wise", she says. "Children can learn lots of facts, but that doesn't make them very wise, or even intelligent. The whole trick is to relate one fact to another, then you have a theory or an idea. And that is what you should be trying to do, not just diet on a lot of facts."

Human imagination and the ability to follow a logical plot line from beginning to end may also become casualties of the information age, particularly if young people abandon books and other pasttimes for computer games and the Net.

"A novel is a narrative [with] a beginning, a middle and an end. It takes you through something. Whereas the Net, you pop into it, you pop out of it. There is no obvious narrative line." While the Net offers a "feast" of facts, it doesn't mater in what order you read them since all the information is presented in parallel.

Novels, she says, also force young people to use imagination to fill in the blanks - an important type of mental exercise they might not get from the Net. In a novel, "you've got the characters and they are very real, but you don't know what they look like as such," Greenfield explains. "You don't know what their face looks like, you wouldn't necessarily be able to paint them - yet they are very real." Greenfield worries that imagination might not develop "if you have someone else's images given to you all the time on a VDU".

While other leading thinkers debate the benefit of standardising nature by removing genetic variations that lead to disease, Greenfield questions whether young people's IT dependence might lead to a different world, one of standardised nurture.

"Imagine a generation brought up on the same software, with the same images. Given that the brain will reflect very much what happens to you, is that going to standardise, therefore, individuals... a kind of standardised nurture?"

Computer games also offer a sanitised type of individuality. "The thrill is par excellence - you are pressing a button and having responses - but it is a very indirect, rather sanitised thrill. It's not like climbing a tree," she says. "The options are all laid before you; they are all numbered and clear, pre-programmed."

There may be one upside to all this, however. The internet, in particular, offers older people a chance to sharpen their mental agility and perhaps, in the future, even to fight degenerative brain diseases such as Alzheimer's. Greenfield's research team is studying neuro-degeneration "at the nuts and bolts level".

By 2025, one in three people in the UK will be over 60. "By the middle of the next century, even with the most optimistic of estimates, the people dying from neuro-degeneration will be more than double what it is now," she says. One study estimates that by 2050, 14 million people in the US will be suffering from Alzheimer's.

Where once older people might find themselves sitting isolated in a nursing home with little external mental stimulation, they might now be able to use the Net to improve brain fitness. As people grow older in some cases the physical connections between their brain cells become thinner. However, mental exercise stops "the pruning back of connections".

"In one study, [of] people in an old age home who were scoring the same on cognitive tests, those that did crossword puzzles within a few months were scoring better than those that didn't," she says.

The critical issue is to get older people on to the Net, she concludes. "It's one thing to say, [with] the Net, you're isolated when you do it - but its better than sitting in a room alone."

The Private Life of a Brain by Susan A Greenfield, published by Penguin, £18.99.