Susan Greenfield acknowledges that research on the effect of digital technology on our minds is still in its early stages, and that screen activities such as social networking sites, gaming and surfing the net have been shown to have positive as well as negative effects.
Her remit here is to investigate whether these technologies have scientifically been shown to have effects on cognitive functions.
She states that she is excluding the effects of internet pornography because “the controversy and debate are obviously not so much about whether it is ‘good’ or ‘bad’, or how it impacts on types of thinking, but more about legislation and regulation.” I disagree – scientific studies that show changes in sexual thought processes, beliefs or practices, and especially changes in brain function as a result of internet porn, are important.
Greenfield is a lucid and thorough communicator, and this book is highly accessible to those with no knowledge of neuroscience. Occasionally, she resorts to clichés: “It is hard to separate the chicken from the egg”, “wine, women and song” and “what’s not to like”. Rarely, her scientific explanations are over-simplified, as when she claims that during exercise, blood carries more oxygen to the brain. Oxygen delivery to the brain is increased during exercise, as a result of increased heart rate and heart stroke volume, but the amount of oxygen that haemoglobin is able to carry does not increase. In fact, the carbon dioxide and lactic acid produced by exercise cause haemoglobin to bind less strongly to oxygen, so that oxygen is given up more easily to the working skeletal muscles.
Nevertheless, this is a fascinating book. Research has shown that there is a correlation between having large numbers of Facebook friends and feeling lonely. Those with low self esteem may worsen esteem further as they tend to reveal negative traits as opposed to positive ones, leading to fewer “likes”. One in two teenagers admitted lying about personal details on Facebook, so there are implications for identity and meaningful relationships. Envy, narcissism and insecurity abound. Reassurance given in person or by phone causes a decrease in the stress hormone cortisol and an increase in the bonding hormone oxytocin, yet the same reassurance delivered by instant messaging has no such benefits. Video games cause surges in brain dopamine similar to that seen in drug abuse, and heavy gaming is associated with attention problems. Learning from screens has been shown to cause understanding inferior to that caused by learning from paper.
That I kept being distracted from my reading to check Facebook was less a reflection on the quality of the book than a sobering lesson in how relevant these issues are.
Mind Change By Susan Greenfield, Rider £30